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Darran

Heavy clutch

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Hi all I have a lupo SDI and  the clutch is heavy sometimes hard to get in 1st and reverse but if I adjust the clutch cable bolts it’s fine again I’ve had the clutch cable replaced a few months ago and the pedal box is ok but the new cable fitted by the local garage looks different to the last one as the last cable had a big white tube which clicked into a plastic bracket on the bulk head but the new cable has a small white tube which is a lot smaller so not sure if this is the makes a difference as it was heavy before but I asked the garage yesterday and he said if you replace the clutch it will make a bit difference as the clutch sprigs go stiff over time so I’m not sure to go with what he says or would trying a genuine clutch cable first 

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Pic would help, but sounds a bit like a mk1 golf cable...?

I recently refurbed the box on one of my SDIs and also had a very stiff or heavy clutch. I can conclusively say that the heaviness comes from friction between the guide sleeve and the release bearing. It looks like what happened was that gunge built up in the small gaps between the steel sleeve (attached to the gearbox with 3 bolts) and the inner plastic part of the releaser. ALL the clutch components were absolutely fine. Just gunge. 

The friction material dust from the clutch plate has to go somewhere, and if everything is nice and dry, it eventually gets blown out through gaps in the bellhousing. No problem. But what I'd noticed is that the primary input shaft seal, which is meant to keep the gear oil inside the gearbox, starts to weep very slightly as it gets old. The rotary action of the spinning shaft or maybe just capilary action allows a very small amount of oil to build up around the guide sleeve. Some of that oil makes its way between the sleeve and the releaser which naturally starts to collect clutch dust. Which then turns into really thick sticky gunge.

The gunge has properties best described as very thick sticky toffee like tar, with fine grit in. Such a high viscosity substance between the sleeve and releaser simply jams the action, resulting in a heavy clutch. It doesn't help that the clutch release bearing lever that presses against the springs moves in an arc, which naturally tries to twist the release bearing when you put your foot on it. When you release, it gets pushed straight back by the springs, so engaging is not a problem- only releasing...

so my guess is that fine metal in your gearbox oil has worn the seal, which is weeping, collecting dust and causing the releaser to be sticky. 

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Thanks mk2 so does that mk1 cable make any difference to a SDI cable and also to clean that releases is it a job when gearbox is out so prob new clutch same time ? 

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Dunno without seeing it....

Cleaning with something like brake and clutch cleaner fluid and a rag would take seconds, but most people don't bother cleaning it. It gets dirty again very quickly (with dry dust). Only reason I investigated the problem thoroughly is because I was curious to know why mine was so damned heavy- I thought that I'd either snap the cable or break the pedal box again! 

I originally suspected that one of the spring 'tines' (i think they're called or fingers?) had snapped causing the release bearing to function at an angle on the sleeve- leading to binding in exactly the way it does with gunge. Obviously in my case, absolutely nothing needed replacing, other than a really good clean. There was wear, but even a completely worn out clutch could never ever cause it to be heavy. But for good measure, while the box was out, I changed all the bearings, seals and syncro number 3. And cleaned the magnet and then flushed it properly. Smooth and light as' now :). It needed it too.

 

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