Mi16 Conversion Clutch Problem

[DGTi 0]

Hi all,

 

Just finishing up my Mi conversion, and having a few issues with the clutch. I have searched round on this subject but not really found anything.

 

First of all I should mention that along with installing the Mi16 engine, I have also fitted a BE1 Mi16 gearbox. My car is a phase 1 1986 (D) 1.6 GTi, and I have swapped out the clutch pedal and cable for a BE3 type.

 

When we first started the car up the clutch would not dis-engage and the gears would just crunch if you tried to select one. So we adjusted the cable and then the clutch wouldn’t engage and you could select all the gears but had no biting point even when the pedal was fully released!

 

After a bit of messing about we finally managed to find a sweet spot on the cable adjustment that would allow the clutch to engage when in gear and dis-engage to select a gear.

 

Unfortunately this has left the biting point right at the top of the pedal and left the pedal feeling rather weak like it is struggling to spring back up as you lift your foot.

 

The mechanic that has been helping me with the conversion says ‘this is the problem with conversions, things don’t work as well as they should, and that the best its gonna get.’

 

I dis-agree and think something has been fitted incorrectly along the way!! Has anybody else experienced similar issues, or have any idea what could be wrong with my set up?

 

 

Thanks again

Andy

[Anthony 1,003]

Something isn't right there at all - the clutch should be as per a standard BE3 car with that setup, and usually will feel much better than the original BE1 setup.

 

Only thing I can immediately think of is that being a D reg, your car probably has the earlier type pedal box that won't take a BE3 cable properly without modification or being swapped out for a later type pedal box (the fitting where the cable enters the pedal box differs on between early BE1 and late BE1/BE3)

[Paul_13 212 1 Cars]

Is it a 1.9 16v mi clutch (push fit) or the 2.0 16v (pull)?

[DGTi 0]

Thanks for the replies!

 

Something isn't right there at all - the clutch should be as per a standard BE3 car with that setup, and usually will feel much better than the original BE1 setup.

 

Only thing I can immediately think of is that being a D reg, your car probably has the earlier type pedal box that won't take a BE3 cable properly without modification or being swapped out for a later type pedal box (the fitting where the cable enters the pedal box differs on between early BE1 and late BE1/BE3)

 

I was told there may be an issue routing the cable through the pedal box by the guy that supplied my BE3 pedal to me, but I didn't find anything obvious... what exactly would the difference be, and could I still fit the BE3 cable through the box without realising it would cause an issue? Could this result in the issues I decribed above?

 

Is it a 1.9 16v mi clutch (push fit) or the 2.0 16v (pull)?

 

I'm not 100% sure to be honest, the clutch came with the engine I bought and was virtually new so we decided to keep it. is it possible to have the wrong type fitted? How could I tell the difference?

[Paul_13 212 1 Cars]

The pull type clutch has the release bearing fixed to the clutch plate.

The push type clutch has a separate release bearing.

 

The push type is what you want.

[DGTi 0]

The pull type clutch has the release bearing fixed to the clutch plate.

The push type clutch has a separate release bearing.

 

The push type is what you want.

 

Ah yeah, the release bearing was seperate! Phew...lol

[Anthony 1,003]

I was told there may be an issue routing the cable through the pedal box by the guy that supplied my BE3 pedal to me, but I didn't find anything obvious... what exactly would the difference be, and could I still fit the BE3 cable through the box without realising it would cause an issue? Could this result in the issues I decribed above?

It's been a couple of years since I've seen an early pedal box so I can't promise how accurate this is.

 

The early pedal boxes use a twist fitting for the clutch cable, whereas the later ones use a push fit rubber grommit. From memory, the hole on the earlier pedal box is a little smaller than the later one, and if that's correct, then I would expect that the grommit won't locate and you'll be flexing that every time you press the clutch pedal, no doubt making the pedal feel horrible and probably making it not spring back properly.

 

Easiest way to check is to make sure the black rubber grommit is located properly inside the pedal box, and that the white plastic is pushed fully home inside. If the black grommit isn't located and won't fit, you might need to file out the hole slightly to allow it to fit.

 

As said, this is going off a hazy memory with regards the difference in hole size/shape on the early and late pedal boxes!

[DGTi 0]

It's been a couple of years since I've seen an early pedal box so I can't promise how accurate this is.

 

The early pedal boxes use a twist fitting for the clutch cable, whereas the later ones use a push fit rubber grommit. From memory, the hole on the earlier pedal box is a little smaller than the later one, and if that's correct, then I would expect that the grommit won't locate and you'll be flexing that every time you press the clutch pedal, no doubt making the pedal feel horrible and probably making it not spring back properly.

 

Easiest way to check is to make sure the black rubber grommit is located properly inside the pedal box, and that the white plastic is pushed fully home inside. If the black grommit isn't located and won't fit, you might need to file out the hole slightly to allow it to fit.

 

As said, this is going off a hazy memory with regards the difference in hole size/shape on the early and late pedal boxes!

 

Ok thats great, thanks for the info!

 

I refined my searches this morning regarding the pedal box after your post, and what you are saying sounds right, and someone did point out that the grommet on mine didn't locate very well at the bulkhead so thats going to be the first place I look!

 

Do you think this will help with the biting point being right at the top of the pedal though?

 

I'm not very well educated on clutches, should I be able to move the bite point higher and lower on the pedal using the adjustment or is there only one point on the clutch that will have the biting point dependent on how worn the clutch is?

 

Thanks again

 

Andy

[Anthony 1,003]

Loosening or tightening the nuts at the gearbox end of the cable will adjust the biting point.

 

Ideally you want it set so that there's a small amount of free play on the gearbox end if you pull the cable (so that it's not constantly riding on the release bearing) and so that the clutch pedal sat is a smidgen higher than the brake - get both of those right, and all else being correct, you'll have a nice clutch pedal with the biting point somewhere between a third and halfway up the travel. I think there's something in Haynes about it, although I've never paid much attention and am not sure if it's worth reading or not!

 

My best guess is that if the grommit isn't located, the first portion of the pedal travel is taking up compressing that grommit rather than operating the clutch, hence you've had to over-adjust the cable in compensation to gain more travel and have ended up with the biting point at the top of the pedal.

[DGTi 0]

Loosening or tightening the nuts at the gearbox end of the cable will adjust the biting point.

 

Ideally you want it set so that there's a small amount of free play on the gearbox end if you pull the cable (so that it's not constantly riding on the release bearing) and so that the clutch pedal sat is a smidgen higher than the brake - get both of those right, and all else being correct, you'll have a nice clutch pedal with the biting point somewhere between a third and halfway up the travel. I think there's something in Haynes about it, although I've never paid much attention and am not sure if it's worth reading or not!

 

My best guess is that if the grommit isn't located, the first portion of the pedal travel is taking up compressing that grommit rather than operating the clutch, hence you've had to over-adjust the cable in compensation to gain more travel and have ended up with the biting point at the top of the pedal.

 

Ok that makes sense!!

 

So locating the grommet properly allows me to loosen the cable, and the clutch will then open with the pedal push rather than the grommet squishing taking up the movement! :-)

 

Is the pedal height adjustable? I think mine is currently sat a fair bit higher than the brake pedal, higher than I recall it sitting with the old pedal anyway!

[Anthony 1,003]

Indirectly, adjusting the cable will move the pedal - too tight and the pedal tends to go up, and too loose and it tends to go down.

[DGTi 0]

Indirectly, adjusting the cable will move the pedal - too tight and the pedal tends to go up, and too loose and it tends to go down.

 

Really? Thats confusing you'd think it'd be the other way around!Lol

 

Either way this sounds like it could be the cause of my issues, thanks very much for all your input!

 

It will be a few days before I can get back down to the car to try this but I will come back and let you know if it cured the issue.

 

Thanks again

 

Andy

[DGTi 0]

Update:

 

Its been a while since I have been down to the car, due to other issues with the conversion and life getting in the way!! But I managed to go and have a fiddle with the clutch this weekend.

 

I opened up the hole in the pedal box using a dremel multi from inside the drivers footwell, with the clutch pedal off the car, and after a couple of hours grinding I had a hole big enough for the grommet!!

 

As soon as it was located correctly and the cable was attached to the re-fitted pedal it was perfect, with a little slack in the cable as described and bites beutifully now!!

 

Thanks very much for your help, spot on as usual!! :-)