Dodgy K-series clutch release bearing -- again!

[John Vine]

In Oct 2001, I replaced the CRB in my 1999 1.8SS (it was truly burnt toast -- following a complete seizure, I believe). Now, after just 6K miles or so, the are signs that the new one's playing up (occasional squeal when depressing the clutch).

 

Is there a design fault here? In over 40 years of motoring in a wide variety of cars, the only CRB failures I've ever had have been in this 7! (I should add that I don't use the clutch pedal as a footrest.)

 

The plus, if there is one, is that I might take the opportunity to drop in a 6-speed box while the engine's out...

 

JV

 

[Johnty Lyons]

There certainly was a design problem but only as far as I know on the earlier 6 speed boxes. The spigot shaft housing on which the release bearing slides up and down was too short, so at extreme clutch in, the bearing was not fully supported by the shaft housing. This was solved by a replacment housing about one and a half inches longer,[and I should have said accomplished by the addition of a steel sleeve] which I fitted last strip down I did 2000 miles ago. However I do not know if other K mated gearboxes suffered same problem or if it was limited to the 6 speed only. [Obviously not].

 

jj

N.I. L7C AO.

Membership No.3927

 

Edited by - Johnty Lyons on 2 Dec 2002 19:05:22

[CHRIS CLARK]

There was a later mod to this too with the ali nose /bearing surface having a steel sleeve mounted over it. This stops the ridges forming on the aluminium etc

 

I have always thought though that the fact that the bearing is always in contact with the clutch leaves to be odd. After all, on 'normal' cars there is a spring to pull the clutch release bearing arm clear of these leaves.There is a lot of heat generated around/in the clutch bell housing & these CRB's are formed of what; glass filled nylon/nylatron outside? Constant spinning bearing? Uuummmm

Answers on a postcard.........

 

Clamshell Club Founder Member and stationary engine enthusiast.

[John Vine]

Thanks for the feedback, folks. My box has the steel sleeve, so it seems the problem is due in some way to either (1) constant contact between the CRB and the diaphragm fingers or (2) the angle of presentation of the CRB at the point of contact.

 

Item (1) was discussed in some depth back in Oct 2001. At the time, I inserted a spring in the pedal box to relieve some of the tension on the clutch cable (a Len Unwin tip). But I'm not sure now that this has helped! And if (2) is the cause, what can I do about it?

 

JV

 

Edited by - John Vine on 1 Dec 2002 18:33:16

[Dave_H]

I fitted a six speed gearbox in the summer (with the new, steel nose-piece) and have covered about 4000 miles since. I also seem to have a bu**ered clutch release bearing. ☹️

[John Vine]

Dave,

Good news about the 6-speed, but bad news about the CRB. Presumably the two events are unconnected?

 

JV

 

Edited by - John Vine on 2 Dec 2002 17:36:10

[Dave_H]

John,

 

I don’t know? The clutch was all new. I’d of thought it would last longer than it has.

 

Dave

[KenEvans]

I too had a major CRB problem on my 2000 model 1.6SS with 5 speed box at 6000 miles. Horrible noises were coming from the bell-housing area. I could see through the inspection hole that all was not well and upon taking the whole lot out found the bearing to have totally destoyed itself falling into several parts as I pulled it off the shaft!! I was a bit peeved to have such a fundamental failure at an early mileage.

 

I took this opportunity to put in a 6 speed box.

 

There have been previous postings on this with contributions from Len Unwin who recommends that another equal and opposite spring be added to the clutch pedal so that it just holds the bearing off the clutch. I've done this and had no problem since.

 

Ken

 

See my classic-style 7 hillclimbing here.

[Steve-B]

Ken

 

did you take any pictures? I have a kinda noisy CRB in our 2002 1.8vhpd 6sp-fwd and was just going to tighten up the cable a bit.

 

now i'm fearful that it may be the bearing. the noise goes away when i push the pedal in, and is there in neutral when the pedal isn't depressed.

 

following this thread leads me to think with 6500 miles i may be going down the same path

 

Steve

Metalic Black SV-VHPD

click here to see our 7 and rallye pictures....

[scooby dooby doo]

a rattling noise when sitting in neutral with the engine running is fairly normal.

 

HOOPY 500 kg R706KGU

[Peter Carmichael]

"Tightening up the cable" is not an option. The cable needs to go the full slack position. The cable adjustment is purely for setting the pedal position.

[charlie_pank]

Can anyone explain what the symptoms are of the CRB being on the way out? I'd previously assumed that the rattling in neutral (they all do that sir) was the beginning of the end, but Hoopy says no (which I'd like to beleive!)

 

C

[Dave_H]

Mine makes a really horrible graunchy noise when I put the clutch down. It only does it when it’s really hot though?

[Andy Best]

Just spent the morning takingthe engine out for this very fault, (thanks Andy and Stu for the help), the CRB was in several bits the symtoms were:

 

1) there was an intermittenet noise when the clutch was depressed.

2) the noise went

3) a new grauncy noise started when cold and changing gear.

4) the cluche pedal started to feel lumpy and gears were difficult to engage.

 

point 1 lasted about 9 months 2, 3 and 4 happened over the course of two weeks.

 

All I need know are all the important bits to change whilst the engine is out VHPD head, RBTB's dry sump kit, an emerald oh and some silicon hoses. 😬

 

Andy

[John Vine]

It only does it when it’s really hot though...

That's interesting. My current problem seemed to appear towards the end of a trackday at Brands. To be precise, I'd just been entertained to a few demo laps by Paul Kite, and the car had got pretty warm! Back at the pits, Paul commented on two things: (1) the CRB noise (confirming my suspicions) and (2) the graunching gears when changing from 2nd to 3rd at high revs (something I'd been aware of for six months or so, but was prepared to live with as I'd put it down to a sloppy synchro). Are these two symptoms related?

 

Several of you chaps seem to have suffered CRB failures. So, to return to my original question: Is there a design fault here? Does anyone know Caterham's view on this problem?

 

JV

[John Vine]

...spring be added to the clutch pedal so that it just holds the bearing off the clutch. I've done this and had no problem since.

I applied this Len Unwin fix too, and thought I'd solved the problem. So I was a bit peeved when the squeals returned!

 

JV

 

[Rob Board]

John. I have just purchased a new 2002 1.8 Roadsport, with 140 bhp and 6 speed box. having only covered 1800 miles, my car has an occassional rattle whilst in neutral. I spoke to caterham who confirmed my belief that it was the idler gear on the lay shaft. This is not an uncommon trait in cars, and this is the third car I have owned that has done it. (Other two not sevens), so as Hoopy says I would not be overly concerned. As far as CRB failure is concerned, as of yet I have not experienced any snags. However occasionaly when the car is very hot , upon depressing the clutch pedal, I get a vibration thru the pedal, along with and audible vibration. If I depress the pedal two or three times in quick sucsession it disappears. Due to my cars limited miles I beleive this to be the clutch plate splines dragging on the input shaft, so causing the CRB to rattle. Hopefully as the clutch beds in this will go. If not it will be a warranty job! If caterham come up with any info should I end up at that position I will post a line on Blat Chat. Hopes this sheds some light Rob.

[John Vine]

Thanks for the info, Rob. Please keep me (and BlatChat) informed on Caterham's comments. In the meantime, I'll ask them myself -- Simon Lambert owes me one for all the nice things I said about his Donington instruction...

 

JV

 

Edited by - John Vine on 3 Dec 2002 12:33:14

[Dave_H]

"However occasionaly when the car is very hot , upon depressing the clutch pedal, I get a vibration thru the pedal, along with and audible vibration. If I depress the pedal two or three times in quick sucsession it disappears."

 

Hmm, that's interesting, I get that too. Apart from the "audible vibration" is more of a metallic graunching sound. It also seems to clear itself by pressing the clutch pedal down two or three times. Has anyone else had this, and taken the release bearing out to find it knackered 🤔

[John Vine]

Dave,

The symptoms you report are exactly what I encountered the first time my CRB played up. When the shrieking noise started, pumping the pedal would eventually stop it. One day, though, I got a horrible metallic scraping that no amount of pumping would stop. That's when I took the engine out, to discover a totally cooked CRB, completely knackered and falling to bits, and with the carrier practically worn away. I don't know why the pedal pumping should have provided a temporary cure, though.

 

JV

 

PS: I've just e-mailed Simon Lambert at the factory. I'll let you know what he says.

[Dave_H]

Any news on this yet 🤔

 

Dave

[John Vine]

Dave,

I had a reply from Simon Lambert, and I've asked him if he's happy for me to post his comments here. The basic gist, however, is that failures seem to be rare and that the (Ford) part is well up to the job. More news later.

 

JV

 

[John Vine]

Dave and others,

 

Here's Simon's verbatim response:

 

I don't think we are going to be able to give a definitive answer without taking a look at the clutch on your car. However, I would say that we change very few bearings during the course of a year due to failure - in any age of car (I think we have done two in 2002).

 

The bearing hasn't changed since 1985 and is the same part as used by Ford - it's more than up to the job (I don't have a record of us changing the bearing in your car, but assume whoever did, used a geniune Caterham/Ford part?) Fitting the return spring may be beneficial, but spinning at engine speed with no load on the bearing is unlikely to lead to failure.

 

There may be some other underlying problem in the clutch which is causing the failure, but as I said at the top, without taking it out and having a look, we can't think what that would be.

---

 

This suggests that, as far as the factory is aware, CRB failures are rare. The experience of this forum seems to suggest otherwise, though.

 

I'm planning to take the car to the factory in the Spring for its annual service, so I'll ask Simon to peek at the clutch. The answer to his question about the provenance of the CRB is that I used the part supplied by Caterham (P/N AB57). It came in a black box labelled "Automotive Bearings Ltd, The Classic Clutch Release Bearing". The label on the box said "AB 57" and "HD 2482".

 

JV

[Dave_H]

Hi John

 

Thanks for that, I was kind of expecting that response from Caterham. So basically they don’t know. Is there a more heavy duty one available from anywhere 🤔

 

Dave

[Rob Walker]

There is another important point to watch out for when installing the CRB. The bearing needs to be checked for being concentric to the support sleeve. If the bearing is installed without cenrtalising the carrier each time the clutch is depressed the steel portion of the bearing scuffs against the clutch fingures prematurely wearing them , causing the bearing to overheat and then the bearing can separate from the plastic carrier. So before installing any new bearing hold the bearing firmly in one hand and apply lateral pressure untill the carrier is running concentric with the bearing. This mechanism is designed to be self centering but in my experience it often fails to do so resulting in early failure.