no clutch!!

[manningpaul]

 

Coming back from the L2B I noticed that on a few occasions that it was difficult to get into first or reverse. Used the car today and no problems in running around until I got to Salisbury. Going through the centre after lots of stop start running in traffic suddenly couldn't select first. Stopped engine, engaged gear and wound over the starter and went a few yards, then couldn't get it out of gear! Another engine off and start in gear but wouldn't disengage .

Parked up and called AA as plenty of pedal pressure and cable all ok, suspect it might be a bent arm although when the AA man looked into the bell housing he said that the arm was fine?

Looks like an engine out job, any suggestions as to cause?

 

 

[Fishy Dave]

Guessing it's not something simple like the adjustment nuts on the clutch cable outer undoing Paul?

The clutch fork on my car fractured but know that the dry sump type is a different design, so unsure if the wet type have the same issues? Either way I'm sure we can get it fixed, we can have a chat about it on Monday at the meet. I have an engine hoist if Philip would let us use his workshop again.

[anthonym]

ift his is a DS K with the Caterham designed Clutch Release Arm and the car is a few years old with the earlier arm, then it is a common problem, the new part has been strengthened by CC does sound like a bent release arm. Inspection from outside will appear ok. A clue can be that all the apparent available adjustment can be or is taken up as seen at the long hole where the arm comes through the bell housing to meet the clutch cable - the bit where you also see the clutch cable adjustment nuts. Indeed I got a tint bit more life by using all the remaining adjustment. Didn't get me home though.

 

If it is this type, mine was engine out, but some say can be done engine not out, but the bell housing has to be separated from engine one way or another. 80 quid from CC when I bought mine.

 

Lots of threads on here. Everyone will also suggest changing the CRB Clutch Release Bearing while you are in there. Search CRB and CRA Clutch Release Arm and Clutch Release Bearing.

 

 

Edited by - anthonym on 11 Nov 2011 23:01:59

[manningpaul]

 

Hi Dave,

 

No, tried adjusting the cable with the AA man and made no difference, apart from pedal pressure and where the bite point should be. Thanks for the option of a loan of the engine hoist, see you Monday.

 

Anthony, sorry should have said that it is a 1800 K Roadsport, wet sump. Did look at your links to historical posts before putting this one up.

 

Guess we will know for sure when the engine comes out.

 

 

[anthonym]

a curious case :-)

do let us know what happens.

[John Vine]

Possibilities:

 

Collapsed/broken CRB (have you noticed any squealing noises recently?)

Stretched clutch cable (maybe caused by broken strands)

Displaced clutch fork (adrift from its pivot pin)

Bent clutch fork (very unlikely if this is the standard Sierra part)

 

JV

 

Edited by - John Vine on 12 Nov 2011 10:12:25

[Mr Locust]

Have had instances where the wire "pivot" in the pressure plate assembly comes adrift. That gives a result where pressing the release bearing against the fingers does not release the pressure on the friction material.

[John Vine]

Another possibility would be one or more broken (or cracked) diaphragm spring fingers.

 

(Edited to add) Or it might even be due to:

 

A seized spigot bearing

The friction plate binding on the splines of the gearbox input shaft

 

JV

 

Edited by - John Vine on 12 Nov 2011 15:54:13

[weeman]

Hi Paul,

I helped Steve Newman do his clutch earlier this year. The reason for splitting the engine and gearbox was to replace the CRB, but we discovered the CRB was not the cause of the problem.

Eventually we (actually it was Steve ) decided that the arm was at fault although initially it looked fine. Tiny hairline cracks were allowing the arm to bend under load and then straighten when the load was off.

I wouldn't want to rubbish your AA man but how he could definitively say that the arm was okay after a cursory glance through the bell-housing is beyond me.

Hope you find the problem and that it isn't too expensive.

While your cars off the road perhaps it's an opportunity too put a few miles on dads 7 😬

 

Post the outcome

 

Be lucky!!

 

Martin

 

[John Vine]

*arrowup*That's interesting, Martin. Is Steve's car dry-sumped?

 

JV

[manningpaul]

 

Thanks for the tips guys, I didn't notice any squealing or undue noises, and remembered today that I used the car on Thursday and it was perfect.

 

Anyway while the engine is out a good chance to put my Silicone hoses on that I bought a couple of months ago and replace CRB etc regardless of what we find.

 

Shouldn't be too expensive Martin as I can't see it being anything to do with the box so just replacement clutch etc. and would you like to bet the likelyhood of me prizing the old mans keys off him

 

 

[John Vine]

I used the car on Thursday and it was perfect.

That does suggest to me that something has occurred suddenly rather than over a period of time. Have you checked that the clutch cable is truly free-running and has no broken strands? These can really jam things up and restrict movement.

and replace CRB etc regardless of what we find.

If you haven't already engineered in the recommended pre-load, I would urge you to do that at the same time.

 

JV

[Luegonigel]

Just had the same thing on my 1800 roadsport. Transpired it was the crb. the bearing was coming away from the carrier. clutch still fine but replaced anyway. Problem bleading air from cooling system afterwards. 3mm hole in thermostat fixed that. gearchange now fabulous. Lubricated gearlever at same time which also gave a big improvement.

 

[weeman]

Quoting John Vine: 

*arrowup*That's interesting, Martin. Is Steve's car dry-sumped?

 

JV

No John, wet sump with apollo (IIRC).

 

Be lucky!!

 

Martin

[John Vine]

Assuming he had the standard Sierra clutch fork, that was a rare failure indeed. Those forks are normally 100% bomb-proof.

 

JV

[John Vine]

Quoting Luegonigel: 

Just had the same thing on my 1800 roadsport. Transpired it was the crb. the bearing was coming away from the carrier.

Sounds only too familiar. Did you increase the pre-load on re-assembly? If not, I fear your CRB may fail again.

 

JV

[manningpaul]

 

Well the engine came out yesterday, sheared one of the bolts into the block at the rear of the water rail! but otherwise not too bad a job. A huge thanks to:-

Phillip for the loan of a workshop and help for most of the day

and Dave for the Engine crane and his help also.

 

Nothing looks to be wrong crb all in one piece and spins freely, arm is fairly heavyweight item and seems to be fine, clutch fingers all ok although it looks as though a new plate won't go amiss??

 

Ordering new bits tomorrow morning and hoping that when we put it back together the problem is cured

 

 

 

 

[Paul Deslandes]

I'm sure I've read somewhere that the forks can crack and flex/bend in use but, when removed, they look ok. I would check very thoroughly that this isn't the case with yours before you put it back.

[John Vine]

and hoping that when we put it back together the problem is cured

Well, that would be a satisfactory outcome, but from an engineering point of view, I can't see why it will necessarily happen. After all, something caused the initial symptoms. Which new bits are you ordering? Have you checked all the other possible causes suggested in this thread?

 

JV

[manningpaul]

 

My thoughts exactly John! Was disappointed when bits didn't fall out when we disengaged the engine or no visible signs of failure in any component

 

However if I we replace the fork, crb and clutch with new items surely that must cure it?

 

No stretch in the cable and it moves freely in the outer casing, adjustment works fine so don't see any need to replace that.

 

 

[Bio]

Also inspect the spigot bearing on the end of the crankshaft.

 

John

[anthonym]

maybe post some pics of all the bits?

 

Never know what the gathered magicians here will spot.

[John Vine]

Quoting manningpaul: 

if I we replace the fork, crb and clutch with new items surely that must cure it?

Well, it will provided one (or more) of those caused the problem. Other possibilities still remain, however, including:

 

seized spigot bearing (as BIO suggests)

clutch fork displaced on pivot

friction plate binding on gearbox input shaft

 

Now you've got the engine out, these items are easy to check. Good luck!

 

Never know what the gathered magicians here will spot

😬

 

JV

[David Mirylees]

Had exactly the same symptoms after a thrash around the LeMans circuit many years ago. Engine and box out in the camp site, cause was a broken Spigot bearing (in the end of the crank). Replaced (very cheaply) and a spare kept.

Suggest you change it regardless!!

[manningpaul]

 

Thanks for that David, will look in the morning and hopefully might find that it is the cause, if not replacing it anyway.