FIAT 127 Mk1 Clutch Query

    Hi all,


    I think my 127 is due for a clutch replacement.


    I had a custom made 5 speed gearbox in it (direct fit box with no adjustment to the chassis needed) but have recently removed it for a very close ratio 4 speed box, the 5 speed was a good touring box but really lacked performance and made the car very sluggish (only finding this out after swapping gearboxes - I have no other 127s here to compare with).


    Just fitting the 4 speed alone has been a day and night difference with acceleration.


    My issue is everything has been good, gear changes good, holds in higher gear under load but this is now the issue...


    The previous owner attempted to fit a DCOE carb and in doing so modified the accelerator cable, failed fitting the carb due to it being too big and reverted back but left the modified cable there in use, now I thought all was fine until I started playing around with the timing etc as I am now running 106 RON leaded fuel, and to my surprise his "mock" accelerator cable setup only opened the carb half way maybe not even to 45 degrees.


    I have now modified this to open 0%-100% and wow what a difference, induction noise is much louder and the car really pulls much harder than before - I must have been cruising around with 15hp before because the difference is quite excessive, in threads on a local forum from the previous owner he was always complaining that the car felt low on power and other cars that he should have been able to overtake used to walk away from him.


    The one issue that has now arised from this additional/regained power is that as soon as it gets to about 4000rpm the clutch will start to let go and it sounds as if the wheels are starting to spin.


    I have adjusted the cable but it is at the point now if I adjust it any more the gears barely change properly and I have to double clutch it, if I then adjust it back the clutch doesn't hold enough.


    There seems to be a small leak from the inner CV boot (the long shaft) - this was a new boot but it seems to be leaking from the driveshaft hole itself where the seal sits on the inner boot, maybe some oil has sprayed up into the flywheel area from this splattering around?


    My question is, I am pretty sure it is the 160mm clutch in there at the moment, I have 2x spare clutches which are used but still ok, although I would prefer to fit a new upgraded version and looking on line there are numerous 170mm versions?


    I am looking to buy a slightly heavier duty pressure plate and clutch as I am going to be giving it some abuse and will be fitting a light weight flywheel and short shifter at the same time.


    Can I use one of these 170mm versions, or is there a 160mm version that has a up-rated pressure plate?

    Salve SBJ01

    Well, if the clutch doesn't hold the rpm's at any condition. Then it is time to replace it.

    The mean reasons therfore are;

    - friction material worn out

    - disk plate blades got week

    - overheating and as conequence thee "vitrification" of the frictionsurface

    - oil on the friction surface

    Last one is normaly the fact when the retaining ring of the crankshaft or gear box entrance shaft are leaking.

    The possibility that the oil from the leaking CV's boots gets there is normally not the fact.

    But remember in the other threat about the extreme lowering of the car? There you got told that if you lower the car to much, the interior of the CV' s boots could scratch and lead to a leak.


    About the diameter of the clutch.

    As we don't know witch modificaton your 127 has already. Basically every Flingwheel and clutch must match to each other. If you increase the diameter you must check if it still fits with the gearbox bell housing. And if so, then you need to adjust the distance and pignon of the starter motor.

    Normally the 127-MK1 has only the 160mm clutch. On later models they got the 170mm Version even with 5th speed and a 180mm for the last MK3 75HP Sport.


    Greets

    Autolux

    Thanks,


    So 160mm is the only way for me then.


    The cv boot leaked before lowering so I know thats not the cause, I fitted brand new boots when replacing the gearbox and this one has leaked from day 1, it leaks from the small driveshaft hole where the shaft comes out, so the oil seal there is not doing its job, the old boot didn't leak but has been thrown out, I already have a modified mount for the boot fitted on the other side from the modified 5 speed.


    Are the upgraded pressure plates worthwhile? - seen here - http://www.abarth-online.de/ep…s/62098439/Products/RCI80


    Or can they be found elsewhere as a kit?


    Thanks

    Did you tune up your engine?
    Because the reinforced pressure plate is only needed when you've increased the power with +20%. For all others a standard plate from any well-named brand will work perfectly.


    Well, do you have a original 5-speed-box in your 127-MK1 with a modified left frame to give space to the bigger gear box? If you have it , then you might have already the 170mm clutch!


    Regarding the CV-boots. Our Member chrisuno did a helpful resume.
    öldichte manschetten und passende lager für viele unserer italiener
    You may measure your driveshaft to figure out if the "newer" system also fits for you. I guess a proper english translation isn't needed therefore, or?


    greets
    Autolux

    Thanks for the link I'll have a look now


    The engine has a few bolt ons, some high octane leaded fuel and utilising a fitted 5.xx final drive using the original 4 speed mk1 box, and will soon have a lightened flywheel and short shifter on which I plan to be able to be pretty agressive with the shifts and box itself so would prefer an uprated unit.


    I was just not 100% on the difference between the 160mm vs 170mm as numerous sellers state the 170mm is for the 903cc as well?


    The 5 speed is now removed, this was pieced together from a mixture of Panda, possibly Uno as well and 127 gearboxes, it accepted a 180mm setup from memory when the car temporarily had a 965cc panda engine but that was removed due to continuous issues and the reliable 903 was put back in with the stock flywheel and clutch, the 5 speed was direct bolt on except for larger tripoids, no modification to the frame needed, there was a 3cm gap to the chassis


    Not looking for all out speed with this car or an all out racecar but a stop light racer will suffice, which is why I am not worried about motorway speeds/rpm etc and 0-60/100 times is all Ill be fussing over, hence the final drive change and the beginnings of some unsprung weight reduction.

    Zitat von SBJ01

    I was just not 100% on the difference between the 160mm vs 170mm as numerous sellers state the 170mm is for the 903cc as well?

    As far I know, the stock MK1 127 had only the 160mm clutch with 4-speed gear boxes.

    While for the MK3 version exist an 903ccm model with 5-speed gear box who has the 170mm clutch in it.
    That could be the reason why some spare parts provider offers both versions for the Fiat 127.


    Well, 100% sure you'll be when you gona check your clutch diameter by yourself.

    Have fun with you pretty lowrider!


    greets
    Autolux

    Thanks,


    I know for a fact the clutch in it at the moment is 160mm as I only swapped the boxes over recently, I also have a couple of spare second hand 160mms but if the 170mm could have fit it would have been a no brainer to buy it which is why I was querying the compatibility of it.


    I'll look into a 160mm setup for my needs.


    Thanks again

    Just an update on this -


    I drained the "new" gearbox oil I filled it with which was Castrol VMX80, this is what was suggested by some local Fiat guys 128s etc as they said this is what they used in their gearboxes.


    This oil lead to 2nd gear down shifts crunching, effectively stopping me from selecting 2nd on slow downs, and then adjusting the clutch to stop the crunching lead to it slipping.


    I ended up draining it and filled it with 20w-50 mineral engine oil and not only the crunching has stopped completely, the clutch was able to be adjusted back to where it once "was" crunching and barely shifting and now not only shifts smooth but the clutch also holds fine in all gears, I can now put my foot to the floor in 4th gear at low rpm and the clutch will hold.


    * Thanks again for the clarification regarding the clutch size I will need, but may not need one for a while now - well.......untill the flywheel gets swapped out anyway.