Clutch release bearing

[quotVernquot]

Horrible loud chattering when I depress the clutch pedal........obviously the release bearing.

Two quetions

1. Is the bearing a Caterham part or something i can pick up locally?

2. As a result of this going, am i likly to need to replace anything else? Bar room mechanic has suggested that the clutch plate may have suffured as a result. Clutch has only done 8000.

Oh and a third question............anyone come up with a way of changing it without removing the engine and gearbox.............no....thought not.

Damn

Look forward to some advice

[Dave_H]

Only done 8000 miles!! My latest one has just started showing signs of failure after 1600 miles. I'm not happy Caterham really should sort this out. Search the archives, there's plenty in there.

 

Dave

 

Edited by - Dave_H on 14 Apr 2003 20:11:29

[KenEvans]

You have my sympathy........

 

1) Don't know if you can get it elsewhere, I got mine from Caterham. I'm sure they carry plenty in stock

 

2) My release bearing failed catastrophically (i.e.it fell apart!) on my 2000 1.6k with a light flywheel and just 6000 miles on the clock. Like you I was very, very peeved that such a failure should occur at such an early mileage – I don’t like taking engines out!! They clearly have a problem here but I don’t know if they’ve fixed it yet.

 

Following that failure I implemented the Len Unwin opposing spring fix at the pedal that holds the bearing off the clutch leafs. I’ve now done 13,000 miles and replaced the clutch plate and release bearing for prudence. Both were fine. There was actually little wear on the clutch despite many hillclimb and sprint starts.

 

I doubt that your release bearing failure can have harmed the clutch plate in any way.

 

Ken

 

Edited by - kenevans on 14 Apr 2003 21:32:05

[SLR No.77]

Engine out unfortunately, but leave the gearbox in - it's a lot easier

 

When you fit the new CRB, you'll find it can be moved a little from side to side on its plastic mount - make sure that it is as concentric as possible with the input shaft. Although there are scare stories about Caterham CRBs, there are many that have done 1000s of miles with no problems. Check the clutch cover "fingers" for excessive wear, but if the problem has not existed for too long, there shouldn't be a problem. Clutch plate should be fine with only 8000 miles, but you may wish to check it out.

 

What engine are you running?

 

Stu.

[Dave_H]

I centralised my last clutch release bearing in its carrier, as I read on this forum that that was the main cause of failure. As I’ve said, this bearing has lasted for 1600 miles.

 

Dave

[Rob Board]

8000 miles? Is the car not under warranty. Or is that 8000 miles since it was renewed. Hope you get it sorted. Rob.

[Dave_H]

So what’s this Len Unwin opposing spring fix mod? Does it fit straight onto the pedal? Any idea how much it costs? Does it really work? I’ve given up with Caterham. I don’t think they really know why these are failing so frequently for some people.

 

Cheers, Dave

 

[KenEvans]

It costs as much as a small selection of tension springs will cost if you can find a local source. I got mine from our local Burgess hardware store.

 

I drilled a couple of small holes in the front of the pedal box for the spring end to loop around. This spring needs to provide an approximately equal and opposite pull to the standard spring on the clutch pedal. The desired effect is that the clutch pedal sort of floats with little tendency to push or pull the cable.

 

I agree with your point about centralising the bearing carrier too! I didn't do this on my first one and I'm sure it contributed towards the failure. Caterham should put it in their build manual!

 

Ken

[Captainbilos]

Centalising the bearing!!!!!

 

Bugger - I changed my clutch plate, cover and bearing at the weekend. I wish this tread had been posted earlier. 🙆🏻

[KenEvans]

Hopefully it's designed to self-centre after a few pedal presses Paul.

[Dave_H]

Paul: It has been posted before - it's in the archive. But don't worry about it, it doesn't make any difference - if it's gonna fail it'll fail anyway.

 

Ken: Thanks for that, I'll give Len a call

 

Dave

 

Edited by - Dave_H on 15 Apr 2003 14:31:43

[Nick Green]

This has been covered before (December last year), but to recap:

 

Firstly, tell Caterham that yours has failed and what mileage it has done. Some there don't think this is a significant problem.

 

INA, the bearing manufacturers, state that the bearing is designed to run "preloaded", with a force of 80-120 N (*not* Nm), about 18-27lbs holding the bearing on to the clutch fingers. At this force, the bearing is designed self-centre. In theory, it should move once to self-centre, then never move again, as it has no further reason to. It is used in a whole bunch of other cars with no problem. The bearing itself is not the problem.

 

My own experiments with a spring balance, would indicate that the bearing is not running with enough preload. Perhaps other people not suffering from this problem is due to their crbs having the right preload. I ordered a spare clutch pedal spring or two from Caterham a couple of months ago, and they are different from the one that came fitted to my car.

 

The spring at the top of the pedal is meant to provide the preload. I've shortened the spring on my clutch pedal, to provide the INA-recommended preload. I have been running the same bearing without any spring at all (effectively the same as Len's opposing spring set up, though you have to take steps to stop the cable dislodging) for 5k or so miles (until I became aware of INA's advice) and have now done another 1500 or so with the increased preload.

 

Time will tell what difference this all makes, but I didn't regard putting everything back as it was before, when the original bearing had only lasted 9k miles, as a sensible thing to do. No spring at all makes the bearing last at least 5k mile. In my experience...

 

Nick.

[Nick Green]

Blatchat gave me an error first time round....

 

Edited by - nick green on 16 Apr 2003 11:38:50