Adjusting the clutch; refilling the steering (PAS) system

Not so much on adjustment... more on unexpected problems! I will post more on adjustment if and when I cure these problems.

Well gentle reader... its getting on to the moment of truth- and I have to admit part of me keeps finding other things to do rather than press on with the task of recommissioning. However- clearly I can't drive the car without steering or clutch so I will need to tackle these. Steering is the more tricky- it might be OK now I have rerouted the hoses and tightened up all the unions, but as this is a bit of a gamble I thought I'd try the "easier" clutch adjustment first!

Ha....!

As you will recall I have fitted (refitted) a replacement clutch with very little wear. I have also fitted a new master cylinder and a new slave so I hadn't expected any problems. The parts manual seems quite clear; the clutch m/c is not located behind the pedal but offset a considerable distance to the right. This means that the pedal can operate the cylinder only by means of  a horizontal extension bar at the top of the pedal that extends across and above both brake and accelerator, to leave the pedal box on the right to join with the master cylinder push rod.  This extension is bent down at the end and drilled to engage with the trunnion on the end of the push rod and the two are secured with a clevis pin.

Similarly the WM is clear There are only two adjustments to be made to the clutch; the slave cylinder push rod is adjusted so that full travel is achieved just as the pedal reaches the carpet during depression- and the pedal itself is adjusted at its upper limit of travel so that there is around 1 cm free play when the pedal is in the "up" position before it starts to move the clutch. This ensures that the clutch isn't being pre-loaded by the pedal. This seems easy enough... although I do wonder about the possibility of actually adjusting both ends of the movement. This is because the push rod is metal and doesn't stretch! If you set the pedal to max push rod movement at the pedal down stroke, then since the push rod is of fixed length (and backwards movement is limited by the holed washer inside the M/C), then the  "up" position must also be fixed. Further the amount of free play obtainable is fixed and limited to the amount the push rod can move between contacting the piston inside the M/C (forward), and jamming on the holed washer (rearwards). Consequently, I can't see what relevance the up-stop adjuster can actually have? However I have adjusted many clutches before so I set about this task with confidence....  BUT this time there was a large and very obvious problem!

The clutch pedal was sitting well below the other two pedals-in fact its only about an inch from the carpet even with the push rod adjusted to its maximum length.

View of pedals- clutch pedal sitting well below the other two.

In fact the pedal's upwards travel appears to be limited by the clutch m/c push rod itself and is still over an inch from the so-called up stop! It can't be pulled any further upwards unless the push rod is first disconnected.

View from drivers foot well- a view I have come to know well! This is looking upwards and towards the front of the car at the pedal box. Pedal shaft visible running vertically on the left in the picture is the clutch pedal.The  head of its up-stop adjuster bolt visible at bottom centre with clutch pedal return spring behind. Note shaft of pedal is well clear of the up-stop adjuster and the up-stop isn't even long enough to unscrew to control this position. There are some rusty tell-tale marks on the shaft of the pedal suggesting that the pedal has been in contact with this bolt head in the past.

As well as this problem with upper travel limit, there is an alignment issue: The push rod is attached to the extension of the clutch pedal by means of a clevis pin and fork shown below. The angle of the push rod does seem awkward- the workshop manual shows this as almost horizontal and directly in line with the cylinder whereas here its clearly not. The push rod has to deviate to the right (left in this pic) and upwards to enter the m/c. Furthermore it doesn't appear to enter cleanly, if the pedal is pressed the rod seems to jam on something inside the master cylinder; it catches and then pushes past again with a noticeable clicking/grinding. I suspect the angle of entry is causing the push rod to foul on the holed washer that it passes through inside the cylinder and which retains it inside the cylinder.

View from driver foot well looking upwards and towards the engine. The rear of the clutch master cylinder is visible with  its push rod connecting to the extension of the clutch pedal. Note awkward looking angle as the push rod has to angle right (left in this view) and upwards to engage the master cylinder.

second view of misalignment

In fact the push rod seems to sit more naturally alongside the clutch lever extension rather than actually straddling it. In the view below note how the line of entry is straightened if the rod trunnion is held against the clutch lever extension rather than straddling it- clutch lever extension visible between my index finger and thumb. This again suggests the lever extension is too short.

Looking up from driver's foot well- clutch m/c push rod disconnected but held against clutch operating pedal extension. Line of entry straightened.

If the clutch push rod is disconnected the pedal springs immediately back against the up-stop. Its smooth in operation and there is no trace of a bent lever- which is not apparently unknown in these cars. 

It seems that one explanation is that the clutch pedal horizontal extension just isn't long enough. However there seems to be nothing missing from the clutch pedal and no sign of it having been cut short or bent out of position.  However my enquiries have revealed that it can bend or twist across the top of the box and on the arm. This means the pedal shaft itself may not be bent and its movement on the pivot shaft may not be compromised even though the lever is bent! This type of damage isn't necessarily visible unless you remove the box.

Alternatively, and my first thought, perhaps the push rod is too short? ...I removed it from the M/C and compared it with my old one... but its the same length!

Comparison of old and new cylinder push rods, LH is my old one and the RH is the new- they are pretty similar and even their trunnions are the same size. Note the domed end to the push rod which limits backwards movement of the rod when the pedal moves up. .

Finally, might the clutch be half depressed for some reason thus pre loading the cylinder? However, the clutch operating arm in the bell housing does have some free play so the clutch itself isn't under pressure.

Overall then at the moment I am a bit puzzled- I suspect I could straighten the angle using a bolt to extend the clutch lever sideways and slip the trunnion over this- that would line up the rod better, although it would create an awkward loading. However this would do nothing about the lack of free travel in the pedal. 

 I am indebted to the forum for considering my problem- the ideas suggested are:
1. Bent pedals ... not obvious...
2. Pedal has moved to left (no evidence that clutch has moved closer to brake pedal, and the whole box can't have moved because there is no room to move the accelerator farther to the left.
3. Pushrod length (see above)
4. Wrong box- the design of the pedal box was changed in '86- perhaps this box/pedal has already been replaced when a previous clutch pedal bent, but the wrong one was fitted? I have checked with Lotusbits who tell me several (8) redesigns were made on this component. However these seem to have affected the  mounting arrangements and brake travel rather than the clutch.
5. M/C fitted wrongly... long shot as this isn't really possible. I've checked it anyway though.

Its looking like more and more like a bent pedal... especially as I have found other reports where the extent of the bend wasn't obvious before removal. I checked out my own blog as to how the thing was when I received the car- I knew these blogs would come in handy! I didn't take so many pics then but looking back at the entry "Clutch hydraulics" shows that in fact the pedal was disconnected when I got the car and the M/C at that time was full of muck (probably siezed). Its likely therefore that the LBPO knew full well that this was a problem and  simply "forgot" to mention it.  I will have to remove the pedal box and probably change it... and I have tracked down the correct box for the year from Lotusbits. However I do worry about the wisdom of simply replacing a bent box with another identical box when they are apparently quite weak structurally. Consequently, I might also see about welding some reinforcing fillets to strengthen the pedal and arm if there is enough room.

By all accounts swapping a pedal box  is a pig of a job and certainly one I hadn't reckoned on doing! I will make a separate blog entry for that job.


Refilling PAS
My WM has no section on steering- seems a bit of an oversight but its possible that my manual has simply lost it. Anyway I do have a section from the Elite and so I'm assuming this procedure will be fine for the Excel.

In the meantime I have tightened and repositioned all  hoses in the hope that leaks might be avoided!

1. Fill reservoir with fluid- I'm using Halfords cheapest! (DII).
2. Disconnect coil positive lead and fuel pump, and  crank motor a few times. Top up and repeat until topping up is minimal.
3. Start motor and run for a short while- I did about 20-30 sec. Top up and repeat until level is stable.
4. With motor running turn steering from lock to lock a few times until no bubbles visible in reservoir. (Care if front wheels raised)
5 Top up again if necessary.

ITS ALIVE!!!!! Testing the Lotus Excel amplifier ab14 ignition module and... Starting!

OK the sparking problems with this car are coming close to driving me insane- a recap is probably in order....

1. Way back at the beginning, connecting up the motor and ignition gave me no spark- cleaning all the contacts especially around the coil gave a nice regular spark at the king lead- but which vanished every time I reconnected the king lead!
2. I then  reproducibly got a spark on starting to crank- then nothing during cranking, followed by a spark when the key was released. That's how it stayed so I started testing and substituting ignition components.

I cling to the notion that this car did not fail during an ignition fault- it must have been running or it couldn't have thrown a cam belt-but it does look like ignition might have been a bit hit or miss even then.

So what have I done?- this is described more fully in my earlier posts- "Oil pressure ignition and fuel..." and "Lucas 157SA ignition switch...." but I summarise here:
I have changed the coil for a genuine Lucas 32C5 type DLB198
I have fitted new HT leads, distributor cap and rotor arm.
Result: No change

The spark on releasing the key was traced to ignition switch failure; probably caused by contact erosion - the ignition was connected in the ign/run position, but disconnected during cranking and the 12V detected at the coil when in the "run" position fell to zero on cranking! This also cut out the fuel pump. Releasing the key restored power to the ign, but the motor was slowing down after the crank so only one spark! I fitted a new Lucas 157SA switch type 3415
Result: Spark on releasing key now vanished; I still have a good, fat spark on first crank but still saw only a weak intermittent spark (or more commonly no spark at all) during cranking. Volts are now detectable at coil, 12V ign on but dropping to  9.9V during cranking .

This could suggest a switching fault- either through pick up or igniter failure. I tested the resistance of the pickup and found it to be 3.25Kohm; higher than the 2.25Kohm value cited by Lucas ... but there is no guide in the test card as to what values are permissible- Luckily I found a later version of card 6 which states a pickup resistance  range of 2-5 k ohm; so I could conclude the pickup was  not at fault. I could find no trace of a break in  the distributor/AB14 wire, neither before, nor after the distributor entry plug.

To diagnose any further really needed me to understand more about how this system is supposed to work- this is the result of my investigations- undoubtedly oversimplified but hopefully essentially correct!

Ignition module function

The coil +ve is connected to the battery as long as the ign is in the run or crank position - thanks to my new switch. This connection is also monitored by (but not controlled by) the ign amplifier. The coil neg (output) contact is connected to the ignition module (inside the AB14 amplifier) which then switches this wire into and out of contact with earth. Each time its earthed the 12V input to the coil  can  flow  through the LT circuit (secondary coil) to earth through the module. When its switched out of contact with earth the current stops and the mag fields collapse, inducing the sparking voltage in the primary coil. The module makes this switch in response to a triggering voltage fed from the distributor pickup to the other two terminals of the module.

So I'm starting at the beginning and working my way through everything again. The following is a test regime I worked out from reading various different sources- it makes sense to me anyway!

Meantime here is a pic for those happy Lotus users in sunnier climes...

Unacceptable face of mechanics in the UK- dodging the rain and ducking under the tarp 

1. Can current switching give a spark?
Disconnect coil positive lead and use a fly lead to connect coil negative to earth.
Remove the king lead and lay it on the block where the terminal could spark - if a spark is present (or fit a spark tester).
Turn ignition on and briefly flash  the coil positive lead onto the coil positive terminal- should give a spark!
This means if a switched current is present the coil will work.
... Well I got a nice fat spark- and that was good news, but to be frank its only as expected since this is a new coil!

2. Test for presence of switched output

Testing circuitry- note the 12v from post D is still present- I just forgot to draw it again in the lower diagram!

Disconnect coil negative and attach tester earth- probe coil positive and crank.

Switching should be evident if the coil is replaced with a 12V LED circuit tester. Disconnect coil positive input (white wire), and connect this wire instead to the positive side of a 12V LED. Disconnect the white black wire from the coil negative terminal and connect this to the earth connector of the tester. The LED will receive 12V as long as the ignition is on, but cannot illuminate unless the coil negative is earthed so that current can flow.
Crank the motor-  if the amplifier works then it will switch the white/black wire to earth and back causing the LED to flash.
... I came up empty with this one and got nothing!

3. Test for switching (pickup output) voltage

Pickup output is generated by the points of the reluctor passing the sensor- this rotation towards, past and away from the pickup generates an AC voltage which should be detectable using a digital AVOmeter set on VAC. So, disconnect the sensor input wire terminal from the amplifier and probe the contacts inside that terminal coming from the distributor. It doesn't matter which way round you probe; you are looking for AC anyway. Crank the motor and observe any AC output.  I think the magnitude and frequency of this output will depend on speed of cranking and and number of cylinders. I don't have a reference voltage for the Lotus but its been reported as 0.15V AC in the forum. That report considered the voltage to be on the low side. For comparison (and of unknown relevance) a V12 Jag using the same system generates between 0.3 and 1.8V AC.

... I always saw a reading here- it was a little variable between 0.13 and 0.3 VAC but there was always something and its a similar size to that seen in the forum! This must indicate that the  amplifier is faulty. Currently the AB14 has the replacement ignition module inside so I will switch back to that which came with the car.

4. Test for amplifier response to  pickup output
I didn't need to do this, I'm listing it as it is the next step if I hadn't been able to find a pickup signal. Its here for completeness.

If the pickup output is absent or suspect, an imitation pickup voltage signal can be generated using a 1.5v pen cell with a 3k ohm ohm resistor in series to reduce the voltage. Install the test LED as above in test (2). Connect the dummy voltage supply you have made to one terminal of the distributor lead input at the amplifier and flash the other onto the second terminal to transiently complete the circuit- If the amplifier is working this should cause it to earth the coil negative wire and so induce a switched pulse  current between from the other two amplifier terminals... which will be visible as above using the LED.

The above processes indicated to me that I had a faulty amplifier module so I swapped that over for the original (the one that came with the car) and tried again- and this time- yes indeedy(!) a regular spark at the king lead. I reconnected the leads and tested again at the plugs- also observing a spark there. Finally, I reconnected the temporary fuel supply and fuel pump before trying again.

Well there was a great deal of nervousness on my part... but after three or four attempts I did generate (at last) the odd detonation or two! I fiddled with the throttle and choke and kept cranking before finally I got a series of detonations and then ...

... IT RAN!!!!!
The video doesn't do this moment of triumph justice but here it is and I share it with the world!

Fantastic news! Better than sex! ... Wait.... What am I saying? Of course it isnt't!!!
I  turned it off smartish as I have to check for water level and fluid leaks but it started and ran quite nicely- all I need is some better weather to try and sort it out a little more....

Conclusions
Well- it seems that I had at least two separate problems (maybe 3) with my ignition system:
1. I do not know if the odd, pierced rotor arm had an effect but it could have been a contributor to my woes!
2. The ignition switch was obviously unreliable and seems to have failed completely during my many cranking attempts to start the motor.
3. The ignition module (the new one I swapped in!) had failed.

I don't think the new coil, cap or HT leads were really necessary- but Hey, they look good and can do no harm! The single fat spark seems in my case to have resulted from module failure, but whether this is diagnostic of such failure I can't tell. I think poor battery would also probably induce the same effect.

If there is a lesson here its probably not to swap too many things at once in (almost) blind panic. I inadvertently made the situation worse by swapping in a "new" Intermotor module, which in fact didn't work and so prevented me from curing the problem by replacing the ignition switch!


One problem I do note is that while running fuel can be seen dripping  into the venturi... I'm not sure if this is just because I have been overplaying the throttle in an attempt to get the things started or f there is a problem with the jets sealing, but the fuel collects in the intakes.

Engine idling- fuel collecting at carb intakes- all 4 show this.

Fuel sender unit: Strip and repair... eventually.

I thought I should also comment a bit more on the fuel level sender and my attempts at sorting it- but its as well to hold my hand up at this point and admit that it didn't go well!  I present therefore an account of my ill-fated efforts and invite you to learn from my experience!

As you may recall the removal and refitting of this part is described under "Fuel system tank to carbs". While I had it out of the tank I did check its behaviour and was reasonably happy... although I now realise that this was largely because I didn't understand how it works! Its a combined switchđ/level sensor in that the fuel level is indicated using a variable resistor operated by the float (max resistance at full, lowest resistance when empty- i.e. the opposite way around to most other cars!). Resistance is infinite when the sender is pulled right up. Low fuel is indicated by a separate switch which turns on at low fuel levels to activate the low fuel/choke warning light. I didn't know I even had a low fuel light!

My tank has been empty for years... you can't get a fuel level lower than that so given that I now know this switch function exists, I had expected the low fuel light to come on when I reconnected the sender... it didn't! I can find power to both variable resistor (GR wire) and low level switch (GB wire) at the sender cover, and if the latter is shorted to earth than the low fuel light does illuminate. Further when the ign is turned on the gauge does gradually move to "E". This means a good deal of the circuitry is OK, but in all likelihood the sender isn't? A new sender from SJS is £48 (and the rest), aftermarket unbranded senders are around £20 new but I don't know if they would fit. It seemed sensible therefore to have a go at fixing it but I was unsure how to do so.

I did find this account relating to an E type Jaguar which uses a similar  sender... in this account the W terminal is the green orange wire (low fuel warning light switch) and the T terminal the green black (gauge). On the bright side this does seem to be a pretty simple concept and I suspect, its nothing that can't be fixed by cleaning or maybe re-bending relevant contacts!- Hah!!!

"... Fuel Sender – stumped but fixed
For some reason the low fuel light on the dash wasn’t working, yet the fuel gauge was fine. The fault was traced back to the fuel sender unit, which has a removable cover plate. So it was easy to gain an understanding of how it worked to control both the fuel gauge and warning light.

W & T terminal mechanisms W terminal- low fuel warning light switch. T terminal- gauge

Low fuel light contact strip

As would be expected, the unit uses a rheostat to vary the voltage drop across the fuel gauge and the warning light is simply a contact switch. However I hadn’t realised they were two completely separate circuits, sharing a common earth – the sender unit housing.

As the float arm rises and falls with changes in fuel levels, its pivot rotates through approximately 80 degrees. Two slider contact arms are attached to the pivot within the unit and therefore follow the same arc. They are also in contact with the sender housing and so are the electrical contact to earth.

Fuel Gauge
One of the sliders runs along the edge of tapered coil of resistance wire which is connected to the exterior T terminal. When the tank is full and the float is raised to its maximum, the full length of resistance wire lies between the slider and the T terminal – a total resistance of 196Ω.

When the tank is nearly empty and the float is at its lowest, the slider will have moved shortening the length of resistance wire between the two. At empty, the rheostat resistance is 18Ω. The fuel gauge is calibrated to display Full and Empty for these two resistance values.

Low Fuel Light
There’s a copper contact strip on the inside of the cover plate which has a small diagonal break in the copper so the two ends are electrically isolated from each other. The W terminal, connected to the gauge, makes permanent contact with one end.

When the tank is full the second slider arm is in contact with the other end of the strip and moves towards the W terminal contact as fuel is consumed. The slider eventually moves across the gap making electrical contact with the W-terminal, completing the path to earth and switching on the warning light.

I couldn’t work out why it wasn’t working. The multi-meter confirmed the internal connections were working correctly. Yet the switching wasn’t evident at the external spade connector. It didn’t make sense as a metal rivet connects the internals with the external spade terminal.

Checking with the multimeter confirmed that somehow the rivet and the external spade terminal were electrically isolated from each other. A dab of solder solved the problem but I still can’t fathom how they could not be in contact with each other."

Thanks to ChrisVine for this text and pics

So I re-extracted my own sender... not too difficult, the fuel tank doesn't have to come right out- you can undo the two side retaining bolts and pull it forward enough to unscrew the sender retaining ring.

Having extricated the sender and tested continuity, it was clear that whilst I do have a variable resistance between the GB and earth as the float arm moves, there is no position where the low fuel contacts are activated and there was always an open circuit between the GR wire and earth. I did try to fix this- but to cut a long story short it wasn't successful! If you want to learn from my experience press on... otherwise just do as I ended up doing anyway and buy a new sender!

The Lotus sender is not quite the same as the Jag model described above but it clearly works the same way.  I haven't been able to find out what other cars share this unit which would I think provide a cheaper swap, but it seems to be a Smiths TBS 1214/013. Its similar to those used on the Landrover series III diesel and the Triumph 1300 (type TBS1214/000), but not I think identical- which is a shame as aftermarket replacement for the Landrover senders are quite cheap. Anyway perhaps the most significant difference from the jag unit is that its held together by 3 bent tags rather than screws.

Two side views of sender

three retaining tags visible.Top left, right and bottom behind float arm.

Other side of unit note screw on float arm.

Its easy to tap the tags upright to separate the sides of the sender unit.

Tags bent opening sender...

 The sender was very stiff to separate and it seemed to me that it would be necessary to undo the screw on the float arm...

Screw on float arm spindle bottom right
DO NOT UNDO THIS SCREW!!!

... but this was a disaster- firstly I now believe that you do not need to remove this screw and secondly turning it can rotate and seriously damage the contacts inside. What is worse the screw simply broke off anyway!

I had to cut it off and grind it flush.However I could still not open the sender because of the two piece contact strip shown here at the bottom and in side view below.

Note contact strip at the bottom- to separate the halves the case has to move down but its not free to do so until these contacts are released.

There is a small pip holding the two parts of the contact together- I drilled this out with a Dremmel and small bit so that the blades could be separated and now at last I could separate the two halves of the sender.

Drill through retaining "pip"

Inside the upper half the contact was similar in nature to that seen in the jaguar- although clearly a slightly different shape. The action of the low fuel switch is however identical and its activated when the upper contact sweeps off the smaller arc of the copper plate and over the discontinuity to earth the other side.

Copper contact plate inside sender- top right arc-shaped  section bounded by the dark lines is not connected to the bulk of the plate. The arc-shaped region responds to variable resistance for the gauge action and the switch for low fuel is activated when the contact crosses the gap towards 3 O clock

The upper plate was very worn, and there was an obvious groove in the copper. However, this was nothing compared to the state of the sweeping contacts which were deformed and bent and were no where near making contact with the wire-wound variable resistor. I'm pretty sure that this damage resulted from trying to remove the float arm screw so again I repeat- don't undo it!

Contacts scrambled and no where near contacting the wire wound variable resistor. note corrosion on the upper contact. The contacts were damaged I believe by attempting to remove the float arm screw.

I was able to bend the contacts back into a reasonable position:

Contacts swivelled to correct position...

... and bend them down to contact the variable resistor strip

I then refitted the back for testing, hoping to see smooth and variable resistance through the GB wire (gauge) and activation of continuity between earth and GR wire when float fully down.

It took a few attempts but I was eventually able to find a  position where both these functions operated. However reassembly presented a little problem as I had removed and ground out that float arm screw. 

I therefore drilled the arm out at 3mm and tapped to M4 so that I could and use a new short M4 screw to hold the arm.

Float arm drilled and tapped

New screw inserted

... and tags turned down again.

This was all looking very promising but sadly this is where it all went wrong. Having reassembled the unit I found that both the smooth, variable resistance and the switch activation were no longer working. 

I took the thing apart again to discover two problems:

Firstly the contact arms had become (perhaps were always) loose on the float arm spindle- this means that they tended to jam in one position and let the arm move underneath them.

Contact arms have become loose

But could be refitted with a star washer.

I could reattach the arms firmly using a star washer pushed over the spindle- however although this gave a nice variable resistance function of gauge operation, the low fuel switch was erratic. 

Secondly, I had failed to appreciate that the connectivity of the copper arm-contact plate is complex. It is not all connected to earth (this is obvious in hindsight since the switch has to function separately from the gauge; if both were earthed then the switch would always be active!). Although I had physically secured the float arm spindle using a screw, this had also created a short circuit to earth meaning that I had now inactivated the switch function I had just restored! There are probably ways of covering the spindle with a plastic sleeve and using a plastic M4 screw to retain it, or for that matter machining a new spindle from PVC, but overall I think the law of diminishing returns now applies .... plus the last thing I want to risk is any potential for sparking in the tank, so at this point I retired, wounded, despirited and in need of a beer!


Well the new sender (used) duly arrived from Lotusbits (I ordered a flowlock as well which came already fitted with its unions so I was very pleased with that) and I will fit it with the new gasket and ring seal I have obtained.

However I also located a second non-functional sender and wanted to see if I could rescue  my original.

This time I took the new sender apart without unscrewing the float arm screw. I just drilled through the contact pip and straightened the 3 retaining clips. The halves then separated- the resistor half just slips along the arm.

Separating the halves of the second sender unit- float arm still in position. The front of the sender can be removed by sliding it along the float arm. The variable resistor in the case top has a shiny groove worn in it.

The second sender was in worse condition than my original since the copper contact plate was far more worn, and there was a deep groove along the variable resistor. The arm can be removed from the resistor half by removing the float and feeding the wire arm through.

Back (copper contact) side of the sender case. Note float arm in position with contacts as they should be. Copper contact is very badly worn in this float. I applied some penetrating oil around the base of the float arm spindle before ...

The contact arms are in much better condition in this unit- straight and unbent. You can see that they should be located one above the other.

... pushing down on the screw head and the spindle slides out of this half of the case.

The float arm and spindle can be removed from the contact half of the case by pushing the screw inwards through the casing so unscrewing it wasn't necessary.

Float arm spindle removed- screw head still in place and visible inside spring

It might be possible to swap the copper contacts or resistors between cases but as these are riveted in (and I don't have any like rivets) this would be a little bit tricky, its easier to swap the arm. I could insert the float arm into the resistor  half of the case from my first sender and feed it through until the spindle located in the case.

Float arm inserted to my other sender body 

... I could then fit the top cover passing the screw through the hole in the case and clipping it into position.

and the cover added allowing the screw to poke through

This restored function of both gauge and switch, but only if the unit was held tightly closed and compressed. It seemed that the arm must be held tight over against the screw side of the case to make good contact with the copper strips inside. This is probably the function of the screw which acts both to hold the contacts against the internal copper but also to dampen out any sudden movements  caused by fuel slosh. Sadly after my previous efforts to fix this sender, the hole in the cover was now a little too large for the arm screw; and if this was meant to act as a friction lock... then it doesn't do so now! Instead I fixed the screw in the pushed-through position by compressing the two halves of the case before tapping the fastener wings over. I then pushed on the float arm so that the screw poked through the unit as far as it could, and fitted a fibre washer as insulator and finally held the screw post in this position with a C clip.

Screw with washer and C clip

This had restored function- I think with hindsight I could have done a better job and repaired my unit without need for a second sender- however I made some mistakes and this wasn't possible. I wont fit this repaired unit because I have a replacement in better condition now but I am pleased to have worked out how this could be fixed.

A brief word about carpets...

When I got this car the floor carpets were in a terrible state- holed and soaking wet! The wetness came from a blocked heater intake scuttle drain which poured out very satisfyingly once rodded through!  I removed all of this wet sloppy mess- the two floor carpets couldn't be saved although the side trim (vertical) sections of carpet could mostly be cleaned. The soundproofing material beneath (I think it was a type of foam-backed PVC...maybe  Hardura?) was also saturated and so was also removed. This dried out nicely given time but the driver's footwell section was broken into several pieces. I used it as a template to cut a section of normal automotive underfelt to replace it and then refitted all of the soundproofing matting.

Drivers footwell- new underfelting cut and installed , original soundproofing material replaced in front of back seat.

I have ordered a new carpet set from Ebay (Car hoods). I got a full set, the colour match seems great and I am hoping that I will not need to change many of the vertical sections. However time will tell....? The carpets are held down by three piece Veltex carpet fasteners. These consist of an anchor stud screwed into the floor, a clip ring section fixed below the carpet which locates on the stud, and a spiked ring section that will disappear into the pile but penetrate through the carpet fabric to attach the clip section.

Veltex fastener - taken from Opas.co.uk although I bought mine from Woolies or Car hoods (Ebay). Undercarpet clip ring top left, above carpet spiked retaining ring (bottom left) and floor stud bottom right.

The first stage is to replace the underfelt and secure it using the stud section of the fastener.  I wanted to install the carpet fixings in the same positions as the originals, so I installed the studs in the holes in the floor as used by Lotus. Studs were attached using a  1" No 6 self tapping screw- stainless marine grade. The head of this screw recesses neatly into the stud and is long enough to penetrate through the soundproofing material and GFP flooring of the car.  I placed an M4 repair washer underneath the stud to spread the pressure across the soundproofing.

Carpet retaining stud fitted to hold soundproofing material (Hardura) in place ready for carpet installation. No 6 screw head inside and M4 galvanised repair washer beneath.

Below the floor of the car the self tapping screw was held by a U section flat nut

End of self tapping screw viewed from beneath the car- note U section flat nut. This should allow some pressure to be exerted on the screw (as in pulling up the carpet) without ripping the screw out of the floor.

The whole of the fastening beneath the car was covered in a blob of Hammerite underseal and finally the sharp threads were covered with a 3mm Bolt Shop (Ebay) vinyl thread cover/protector.

Nut and screw below floor

Underseal added (contains waxoyl)

Thread protectors fitted.

I think the thread protectors are to stop me being sued by any mechanics who might work under the car- I doubt they do much to preserve the thread.

Fitting New Carpet.
The new carpet set arrived from Carhoods via eBay Its a nice set and although the colour is slightly lighter than the originals, its not enough to offend me- although the purist might not like to see new and old mixed. It includes the handbook pocket on the driver's side of the transmission tunnel which I wasn't expecting. The set is slightly different from original in that the front and rear foot well carpets are shorter and don't actually meet under the seat. There is a small square of carpet to cover the gap. This is not edged- which I think is a shame as its impossible to avoid joins with two raw edges with this system. Of course this will be under the seat and so will only show when the seat is tipped forward ... and perhaps revealed to the entering passenger. That may not make a great impression so I think I will have to be creative with carpet tape and see if I can disguise the join. Quality seems fair but the carpets are not as solid or robust as the originals.

Anyway- I'm hoping not to change (yet!) the glued-down sections of carpet along the transmission tunnel and inner sill edges. These do need changing, but they aren't too bad and as the colour match is acceptable (to me anyway), I will go ahead and fit only the foot well carpets. I have more than enough other stuff to get on with at the moment.

I am fitting new carpets over existing mounting studs so I don't have the luxury of working from the top down- I have to start at the stud and work up. There are loads of different ways of locating a new clip ring over an existing floor stud. Many of these involve just making a hole with a narrow sharp spike to locate the hole position. I don't like doing that- well it leaves a hole in the new carpet, so this is my way. If following it watch out for your finger and thumb tips!!!

Here's the below carpet ring set, spike ring and clip ring. 

assemble it with the spiked ring below the clip (ie upside down!)

Clip the assembly with the spikes upwards over the stud and then carefully position the carpet (engage any existing studs if available). Make sure the carpet edges come where you want and then...

Push the carpet down over the spikes- until they pop through to the top of the carpet. There is one here; they are hard to see but believe me you will feel them! Watch out for your fingers- don't want blood spots on the new carpet!

Position a new spike ring to coincide with the spikes coming through from underneath. If you match the teeth then they will also penetrate the clip ring beneath

Holding the upper ring in place, fold the carpet back and locate the three spikes penetrating the carpet

Slip an new clip ring over the spike tags and hammer them flat with a punch. This also pulls the ring into the carpet pile

Clip ring fitted

Remove the guide clip and spike ring from the stud and clip the carpet down.

Leave the new stud fastened when you do any others to ensure that they all fit well.

Carpet work was stalled for a month or so- whilst I was stymied with the fitting of my new pedal box (see later post). Removing the pedals obviously opened up access to the firewall bulkhead and so this was an ideal time to swap those carpets at least.
The driver's foot well end carpet is not in bad condition but pretty mucky. However this carpet also overlaps the side pieces and the the internal transmission tunnel section on the driver's side which also had a few problems: The handbook pouch was split and the edge whipping was worn through in a couple of places. This being so I decided to change the tunnel side section (drivers side) carpet as well and this piece needs to be fixed in place before the footwell end carpet. Both sections of carpet need to be prepared first.

However I set about preparing the foot well end and its carpet first. Later cars had a metal pad to prevent the throttle pedal from wearing out the carpet. My car didn't have one and as there was no hole in the wheel arch I am assuming that one was never fitted.

End of foot well- dirty and grubby carpet

 Foot well cleared out

Carpet removed, note steering column on the right- I need to cut out a hole for the new carpet to go round this. 

 Here the new carpet has been placed on top of the new piece from Car Hoods- fit isn't bad. The hole required to surround the steering column is visible- so I cut this out from the new carpet.

Old carpet on top of new for use as a template. steering column hole top left.

This was the first time I got the chance to work with the Car Hoods product. I have to say that you get what you pay for... this was  a fairly cheap set and the carpet is thin and tear-able; the density of the fibre tufts also appears lower than on the original carpet. If I can get it installed and stuck down then I think it will be fine, but I thought it sensible to take a few precautions to limit tearing.

 Firstly, I applied carpet tape to the rear to help bind any cuts,

Tape to rear of carpet- reinforcing all cutouts

Secondly I used a general purpose glue to massage into the cut edges to help bind the threads and prevent fraying. I did this to all cuts and holes but I'm not going to mention it again. Hopefully this will help to make the carpet set more durable.

Glue worked into the edge of all raw cut edges.

Once this part was prepared I set about preparing the tunnel side panel- you need to release the centre console to get underneath it. Firstly, lever up the front tray compartment under the handbrake. You can then slide it to the rear (ie under the handbrake lever) until it clears the radio at the front, then lift it up at the front (radio end) before raising it and rotating it around the gear lever to clear the console.

Raise and rotate the gear lever gaiter and tray.

This exposes the two fixing screws below the tray. You don't need to release the third screw that holds the handbrake gaiter in- this will raise with the console.

Two console screws below the tray

The console can then be raised a couple of cms which lets you pull the carpet out from under it- and of course to slip the new one in. Take care not to damage or disconnect the window lift motor switch connections. Other fastenings that go through this carpet panel also have to be removed: there is this stud in the driver's foot well (holds on the knee pad trim).

There is also the seat belt stalk fastener. This is a 17mm bolt head and fortunately a captive nut so it just unscrews.

Make a note of the order of the fittings- there is a spring washer under the bolt head and a spacer beneath the seat belt stalk that penetrates the carpet.

 Having removed the stalk the wiring for the seat belt warning switch is seen penetrating the carpet.

 This wiring is joined to the loom via bullet connectors beneath the carpet. This would be a perfect place to disconnect- except that in my case both were corroded.

 Although they were still in electrical contact, they didn't come apart easily. In the end they broke, so I simply cut them off and replaced them during the rebuild- remembering some dielectric grease as this is obviously a spot for corrosion.

 The bottom of the tunnel side carpet tucks under the floor moulded shoulder section. Folding this back revealed two stacks of washers; spacers that are necessary to raise the seat- these were carefully labelled so they get put back in the right place and stored.

Folding the floor shoulder section back

stack of washers to support seat rails

 Finally, I could remove the carpet section from the tunnel sidewall.

Carpet stripped from under the console

Sidewall and firewall both clear

The new carpet section was considerably larger than the old, the bottom section seemed to match but this left the top far too high

I aligned the two sections in order to trim the new one to size. Since the bottom edge was already cut, and is by far the more complex, I aligned the base and trimmed the top (and any sections that appeared to be extra at the bottom). Note- the old carpet had a clear cutout at the front - right lower in this view, and the I also cut this out of the new carpet (see below). I had assumed that this was cut out for a reason but in fact it serves no purpose and I should have left it!

Old and new carpets aligned. Note the new carpet has a lot more material to the top. The pocket stiffener has been removed and visible above the carpets.

Cut out new carpet- probably cut too small. Note functionless cutout at bottom right.

This generated the new carpet above; but I later realised that this was a mistake: the new set isn't a Lotus original; the other sections do not have the same overlaps so using any single piece as template has to be done with care. In particular this tunnel side carpet really needs to cover more of the foot well floor in order to meet up with the new floor pieces. It should probably have been placed lower but obviously position is limited by the handbook pocket which must be above the floor. Perhaps fit would be easier if the pocket were attached higher on the new carpet. It would probably have been more sensible to align the top and fit the carpet before trimming the bottom in position and just ignore the Car Hoods bottom profile. I did get away with the approach above; but its not great and I wouldn't do it that way again.

One other point is that the old set had a plasticised stiffener stuck to the front of the owners manual pouch- this isn't included in the new set so I removed it to stick into the new carpet after fitting. It needed minor trimming as the new pouch isn't quite the same size. Also, given that the new carpet is thinner than the old (and even the old one had split here) I think I will need to make some form of reinforcement pocket for the inside to take the owners manual.

In order to fit the tunnel side piece I first of all aligned the new carpet with the floor and the top of the centre console- pushing it well into the foot well. I could then hold it in place but peel it back at the front and spray the front side of the foot well and the rear of the front of the carpet; allowing the solvent to flash before pressing it back into position to hold it in place whilst I fitted the rest of the carpet.

Front of carpet tacked in place with glue.

 I could then spray the rest of the carpet underside and the tunnel side before sticking it into place as before. I had to make a few cuts in position and tucked excess carpet beside and under the rear seat and console. I then refitted the seat belt stalk, front knee pad stud and pushed the wires through the carpet making new connections underneath. Finally, I gave the last sections  of the tunnel side (carpet back and tunnel side wall) a spray and stuck the carpet down as above. I could then move on to the foot well bulkhead  section.

Tunnel side piece stuck into place- seat belt stalk refitted and connected.

The shoulder sections at the sides of both floor sections cover the seat mounting points. They are glued to the car floor but also fixed to the rear foot-well carpet using Veltex fasteners- but with a modified fitting. The upper section is fitted to the rear foot-well carpet in the same way, but for these fasteners, the button onto which it must clip is inserted in the shoulder section carpet rather than the car body. I did this using washers and pop-rivets.

Veltex fastener-lower sections and pop rivet. The original fasteners fitted to the car were the black type shown above (LHS). These had no flange and need a washer (shown below) underneath them to stop them just pulling through the carpet. The more modern type (silver, RHS) have an integral flange making this second washer unnecessary. The pop rivet is inserted from the rear through a second but smaller load-spreading washer under the carpet, and then expanded into the button of the Veltex on the top of the carpet.

Veltex button pop-riveted into the carpet.

I test fitted the rest of the carpets to make sure that all overlapped- the fit isn't bad but I had clearly cut the tunnel side carpet a little too small. There is also the strange square gap in the middle under the seat where the rear foot well carpet doesn't overlap the front.

Gap between front and rear footwell carpets

Infill piece supplied to cover this- but note raw edges.

There is also the odd junction of raw edges in the centre of the seat position which I think I had noted earlier. The square section supplied was only just large enough and should cover the junctions adequately. I need to investigate the use of carpet tape to try and hide the raw edges but they should be hidden beneath the seats anyway.

Tunnel side and front bulkhead carpets fitted; remainder tested for fit but at this stage still loose.

Later, when I returned to fitting the carpets  more permanently, I did discover a problem. The fit test shown above was carried out with the car "A" post trim panel unfitted. This is the section of trim that clips to the door frame and extends around the inside of the car to cover the inside of the foot-well by the fuse box. This section of side trim is shaped; it has an obvious square indentation- and the driver's foot-well carpet is shaped to fit into this indentation. However, the driver's carpet must be moved forwards from the position shown above in order to match the A post trim profile, and this obviously makes the gap between front and rear footwell carpets bigger. In fact its clear that the square fill-in patch supplied to fit between these rear and front foot-well carpets is just not big enough!

Infill square- maybe big enough- but only just! It seems to me that there is going to be a gap somewhere and I cant avoid raw side edges.

The raw edges are still a problem and to my mind the best solution would be to obtain two new "T" pieces for the rear foot-well which have longer "stem" parts; the stem of the current mats is 29cm and this really needs to be much longer at 49cm in order to slip under the front foot well mat and cover everything.  If these were to be edged all around they will eliminate the need for a square infill piece completely as well as hiding all the raw edges. I will investigate the provision of pieces like this.

Spoke to Ian at Carhoods. He seems understanding about the problem. He asked me to cut a paper template for the missing section. I cut one that is a bit larger than the bare minimum, giving a curved overlap with the side shoulders so I can put Veltex fasteners in there. The section is handed and needs to be made using the template both ways up to make LH&RH versions and it needs to be edged along the long sides. I will have to wait and see what happens now!

Template drawn on brown paper.

Carpet sections as received

... and then placed in position- Generally I'm pleased with these as the curve does fit over the shoulders nicely. I need to get the various sections stuck down and put in a few more pop fasteners to hold the sections together.

I fitted the carpets with new fasteners to join all sections together using the pop rivet method to fix the base studs into the lower carpet as above. I was then able to stick the shoulder sections down (including the washer stacks used as spacers under the seats).

... before refitting the seats themselves. For method see my other post here.