clutch

[markandsuefoss]

Drove the car yesterday and parked up for about 20 minutes, but on leaving there was quite a strong vibration on lifting the clutch pedal as I moved off. The clutch seems to engage and disengage OK and the noise isn't there when driving along - only when engaging or disengaging the clutch. There seems to be the right amount of adjustment at the pedal. Ideas anyone?

What's the opinion of replacement clutches - I see there are three possibilities. I thought I'd avoid the pattern parts and go for the Borg and Beck, but is the AP Driveline original specification option really worth the extra money?

Thanks.

[les]

You could check the cable retaining the gearbox to the rear crossmember is secure or indeed not broken.

[ianmack]

Also check the tie rod from the cylinder head to the body, and the engine and gearbox mounts.

[dalebrignall]

the ap driveline is well worth the money borg and beck is now made in china and sub standard

[oliver90owner]

Apart from the engine and gearbox restraints, it could be oil/grease on the clutch drive plate. A 'judder' rather than a vibration is likely a symptom of a lubricated clutch plate. Over zealous application of 'copper slip' at assembly has been found to be the culprit before now. Fingers crossed that it is restraints!

On clutch parts, I would expect most or all the clutch parts are sourced from China. Quality control and setting tighter specs at the production stages are likely the difference between the good (more expensive) and not so good (cheaper) replacements. The usual 'you pays your money and get what you pays for' applies here just as in many other scenarios.

[markandsuefoss]

The engine mountings etc look OK. Not sure how old the clutch is - the engine has done 114 000 miles. Can the clutch become contaminated with engine oil in some way?

[liammonty]

In a word, yes! Have a look under the car to see if any oil is dripping from the hole in the bottom of the bell housing, which has a little 'jiggle pin' poking out of it. If there is, pop some clean paper under it and see what the oil that drops into it looks like. If it's clean, it's likely to be leaking from the gearbox. Dirty means it's from the engine. If that's the case, check to see the engine breather system is working as it should - if it isn't, it leads to oil being pushed out of the crankshaft oil 'seal', which isn't really a seal at all and is easily overwhelmed by crankcase pressure that can be caused by blocked breathers amongst other things.

If it turns out there is a lot of oil in the bell housing, that could be getting into the clutch plate, leading to clutch judder.

[markandsuefoss]

Thanks for that. There is a drop of dirty oil hanging from the jiggle pin. I have removed the pipe that leads from the engine breather to the carburetor and although this is patent (it is easy to blow through), it is oily on the inside. How do I check the rest of the breather system. Do I simply remove the engine side plate that has a pipe leading to a chimney like tube (sorry don't know what that is called) to which the rubber pipe to the carburetor is connected?

Presumably the rear crank shaft oil seal 'weakness' can only be solved at the engine rebuild stage. That would be beyond me - I'd get professional help to do the clutch, but slowly I'm leaning to do more things.

[liammonty]

It's quite likely that the chimney-shaped canister you refer to is blocked - it would be worth checking out. I remember that philthehill posted some pictures on here a while back of one that he removed, and the gunk that was in it. Other than that, it is a case of ensuring that the rubber breather pipes aren't blocked, and if your car has a breather on the top of the rocker cover, that is also very likely to be blocked with 'mayonnaise' - an emulsion of water (condensation) and oil. If you have one, you can whip the rocker cover off to clean it out (simplest to do it when you are adjusting the valve clearances and have to take it off anyway!).

In terms of the rear crank oil 'seal', it is in reality just a scroll on the tail of the crankshaft, that runs very close to a curved plate attached to the back of the block. There's not really much to go wrong with it if it hasn't been disturbed, unless the bottom end of the engine is seriously worn and allowing the crank to move more than it should. By design though (it essentially 'winds' oil back into the engine with the crankshaft rotation) it is easily overcome, which is why any excess crankcase pressure (which could be caused by either blocked breathers, or if the engine is worn, piston blow-by) forces oil out past it and into the bell housing.

I'd ensure the breathers are clear, as you are already doing, and take it from there.

[philthehill]

This is what you may find in a canister oil separator instead of the nice clean gauze.
The canister that this load of cr-p came from was completely blocked and any engine breathing would have been non existent.
If blocked you can poke around in the canister with a piece of welding wire to get rid of the cr-p, flush thoroughly and fill the canister with stainless steel pan scourers. Make sure the pan scourers are tightly wedged into the canister.
The original gauze is/was held in place by one or two spring clips (which can be seen in the photo below) but if the filter is blocked they are usually rusted away.

[Andy W]

Ifyou do need to fit a new clutch.....I have just fitted the AP kit (sourced from DMG at a much better price than everywhere else due to MMOC members discount).

I spoke to ESM who said they have just had to send all their Borg & Beck kits back due to poor quality.
This is the 2nd time in a few years they have had to do this & their workshop will only fit AP.
I spoke to a professional Minor restorer I know, he also will only fit AP clutches.
Dale is quite right that B&B are now cheap Chinese products - I learned that B&B is now just a brand name owned by an investment company.

My clutch is now frankly awesome compared to how it has ever been!
I am absolutely not a mechanic but being basically a giant Meccano job I did it myself with a pal's help & I think it's well worth buying the best - I only wanted to do the job once!

[philthehill]

Me thinks back to fitting/riveting new linings to the driven plate and fitting new springs to the clutch cover.

Do not try this - during WW1 the clutches of the Rolls Royce armoured cars operating in desert terrain would slip and the floor boards would be lifted a handful of sand picked up and thrown into the clutch to give the required grip. To dangerous to go outside the armoured car to fix the slipping clutch.

[markandsuefoss]

Finally got this replaced with an new AP clutch which is great. Verdict on the vibration - broken anti-rattle springs.