Suspected clutch seal issues

[TimJM]

I have a problem with my clutch and would like to ask the PH collective on where they think I should be looking. I will try and give a full description of the symptoms:

The car had a problem with the clutch about 4 months ago when I left it in 1st overnight (due to being parked on a steep hill). The car was difficult to get out of 1st in the morning before starting and then wouldn't go into gear at all. It didn't grind the box it just wouldn't go into gear full stop. I checked the fluid level which was at max and tried again - after 5 minutes of pumping the clutch it engaged reverse, after a few more attempts I managed to get 1st, then 2nd then after driving for a mile or so all gears were back and the clutch was operating normally.

The car drove fine and the clutch worked perfectly for the next four months.

I have been driving one of my other TVRs and the Cerbera has been parked on my drive for about four weeks (not in gear). I just tried to go out and the clutch feels like it did when I had the problem before. I can't engage any gears.

The clutch pedal has pressure but it does feel like less pressure and the pressure isn't always consistent on pedal presses. The footwell doesn't show any visible sign of fluid - I can't really check under the car as it is parked on yellowish gravel and difficult to see and fluid.

The clutch was replaced about 5 years ago but in that time it has done less than 5k miles.

In my mind it feels like seals but I would like to ask peoples advice on here before I start diving in. I may have to attempt the job myself as the car isn't in a great position to be recovered - having said that it isn't in a great position to work on either (outside and on gravel).

I have tackled plenty of jobs on TVRs over the years but never a clutch. Any help/advice greatly received.

[TimJM]

scerbera said:

New owner here,

having just replaced my master and slave units I can tell you that the master is a simple job and can be done from footwell and panel in the engine bay. The slave you will need a lift for.

I would suggest letting brake off and engaging gear it will go in fine once car moves slightly, then you can engage starter motor for a second in reverse and 1st. You may find it frees up. Have had that happen once on a bike clutch. If not then seals to be suspected.

Thanks for that suggestion - I didn't think about that and I suppose being outside and in the rain for a month may have caused the clutch to seize. It may also nicely explain the same problem when I left it in gear overnight.

So to confirm - the procedure here is (without engine running) get the car into a gear (reverse or 1st) by rocking/moving it. Then press the start button with the car in gear and see if the bump frees it off.

[TimJM]

jamieduff1981 said:

The gearbox can be removed with the car on axle stands. I did it in February last year on a stoney driveway. A lift or even my new big dry shed/barn thing would be much more comfortable.

If fluid is going to the slave cylinder but not declutching, then it needs to be leaking out of the bellhousing - i.e. it has to be going somewhere. It could indeed be a seized clutch, and that the slave cylinder is indeed stroking but you're just bending the clutch fingers. If that were the case, I'd still want to remove it to inspect the fingers. They are not the most robust on these as I'm sure you know.

My bet is the master cylinder seals. It doesn't need to be leaking in to the foot well. The piston seal just needs to be perished enough to let fluid pass rather than be displaced down the hydraulic tube to the slave. Mine fit that description well. Have a look in the reservoir for dark clouds or particles.

Thanks - I will get the clutch cover off and check for particles/seal remains. I am keeping my fingers crossed as the easiest/cheapest fix seems to be the master cylinder.

[TimJM]

Thanks for the advice. I now have a plan of attack for Saturday morning.

I am going to inspect the fluid, if all clean bleed the clutch. If that doesn't help I will try and bump the car in gear to see if it is seized. If all that fails and assuming the fluid as clean then I think I am looking at a slave issue or fingers.

However, even if I suspect a slave issue I will probably replace the master first anyhow as it sounds like the easier job and even if the fluid is clean in the reservoir and the clutch is bled you never know.

Fingers crossed (excuse the pun).

[TimJM]

Looks like the issue is catching - three Cerberas all with the same symptoms now!

I still have my fingers crossed that I will open the clutch fluid reservoir and see bits of the master seal or no fluid. No fluid would be less desirable though as it must have gone somewhere.

If all looks well then yes, I will let the car idle for 10 minutes and get it nice and hot before attempting to start it in gear to see if it is seized to the flywheel.

[TimJM]

I managed to get around to my car a little later than planned today (isn't that always the way with Saturdays) and I think we have a suspect. I think the master seals are shot...they seem to be mostly in my clutch fluid reservoir. At least that's what I think it is. I will post up some pictures later but the clutch fluid is now black and full of what looks like small rubber particles.

[TimJM]

Here are a few pics I took. The black sludge was all over the cap and throughout the fluid.




Here you can see some of the particles:


I think this is probably whats left of my master cylinder seals.

[TimJM]

I haven't got round to fixing mine yet. Been flat out with work.

I am going to try bleeding the clutch (not that it will help) but I just want to get all that crap out the system. If the clutch works well enough for a 15-20 mile drive I can get access to a proper lift and it will make the job much easier than my gravel driveway.