Clutch Trouble

[rytaylor]

Well after a nice wee run out today at Vauxhall I started to have a bit of bother getting into first from neutral in the stop-start traffic on the m25.

Couldn't get into reverse to get into my drive without switching the engine off, into reverse then turn on again! Just tried everything again there now that the cars cooled down and all still the same.

Any ideas? Checked the fluid and its full, albeit dirty but was changed 2k ago. Time for an ls7 clutch?

[rytaylor]

Hmm, sounds promising. I thought it was new clutch time and was preparing for a £700 bill. Will flush the fluid out with new and see how that goes.

It was very difficult to select any forward gear though, not just first and reverse was impossible... Hopefully is just old fluid.

[rytaylor]

neiljohnson said:

Sounds like a hydraulic issue of some sort as others have said changing the fluid wont hurt but also have a look underneath around the front of the gearbox & see if there are signs of fluid. If there are its likely the slave is on its way out & will need replacing asap.

Actually I was going to give you a call to discuss this mornibg if that's OK Neil?

I think it may be hydraulic as its intermittent. Sometimes its impossible to select a gear, as if the clutch isn't disengaging. Others its as good as new.

Fluid is topped to max so doesnt seem to be leaking.

[rytaylor]

SturdyHSV said:

Indeed, but Tickford (and presumably enterprising others) will put TR6060 internals into a T56 housing, giving you the T56 Magnum

Just to include something topical, before changing my clutch fluid I was having the same sort of problems, difficult to get in gear etc. The difference in the level of resistance is quite surprising really!

Edited by SturdyHSV on Monday 21st July 08:49

hope it doesn't come to getting a new gearbox!

Hoping a fluid change will make a difference as you say but the change was quite sudden and is intermittent so it's like something has given up rather than a deterioration in fluid.

[rytaylor]

I'll try flushing some fluid through this evening and see if it makes a difference. Its booked into a local corvette specialist on Thursday for a diagnosis so should get a better idea of what's up with it then.

Thanks for the help so far all.

[rytaylor]

An update on this seeing as I've had a clutch fluid flush carried out.

There has definitely been an improvement. Gearchange is much smoother than previously.

However, since the fluid change it has refused a gear once in around 10 miles of driving. So looks like the problem is still there. I'll try an extended test drive this evening to know for sure.

The fluid change was definitely worthwhile - it was black and seriously full of dust. I'd recommend it even if you aren't having any problems.

[rytaylor]

KMud said:

Was it cold at the time, and at low speed? Could be normal.

It was hot and from stopped. It wasn't as bad as before and did go into gear on the second try. I'll give it good drive and see what happens.

[rytaylor]

Been out for a long drive this morning to see how the changes are.

From cold the changes were super smooth, and then later on changes were still good either at high or low revs. I thought it was cured.

But its not. After stopping at traffic lights for a minute it was difficult to engage a gear. Same story waiting at lights before I pulled into my drive.

So it looks like its only a problem when hot. When you get moving again and get a bit of airflow the changes go back to being super smooth! Dont know what's going on!

[rytaylor]

EmmaJ said:

Have the slave cylinder been changed? Not as cheap as swapping the fluid but might be worth a try?

Yeah, I think that's the next step. Time to give Neil a call I think!

[rytaylor]

007 VXR said:

Do the bearing at the same time.

Yeah, of course. That and the remote bleed.

[rytaylor]

EmmaJ said:

Seeing this thread prompted me to check my clutch fluid. It's never been black before but is now

Now do I mess about with my remote bleed or wait till I go to the fish on Tuesday...

If you've got a vacuum pump then its easy enough. If not, I'd just wait til Tuesday. Especially if its working fine at the moment.

[rytaylor]

neiljohnson said:

I think snowolfs pretty bang on with his theory although I know of no other car that pollutes it's clutch fluid so badly & with such a small resovior it really doesn't help I going to see if I can find a resovior off another car that will not look out of place but has a larger capacity & see if it will help

On a side note a lot of cars now have a feed from the brake resovior for the clutch the amount of crap the ro's & r8's get in the fluid this would not be acceptable!!

I was thinking the same about a larger capacity reservoir. Mine has discoloured already after a full flush and only 60 miles!

[rytaylor]

dsmith1990 said:

Just got mine back from MF yesterday and they replaced the clutch slave cylinder as it appeared the fluid level had been dropping. Turns out it was pretty knackered and got to say I noticed a difference driving it home. Sounds like the same kind of issue on yours...also an 04 VXR?

Yeah a 2004 vxr as well. 10 years and 97k miles isnt too bad an innings on the slave cylinder. Assuming that's what's causing the problem on mine. Oddly I haven't lost any fluid at all.

I'm really looking forward to having a nice gear change again. Its so frustrating when it just decides to stop selecting a gear!

[rytaylor]

SturdyHSV said:

I also find my shifts get more difficult once it's hot. I was wondering if relocating the reservoir (and making it bigger) would help at all?

Surely even just getting it out of the engine bay would mean a lot of the ambient heat wouldn't get into the system, and if it was somewhere cooler, more of the heat could escape the system through radiation.

Seems like it would be a negligible amount, but with people finding that those alloy reservoirs meant the fluid kept boiling, perhaps the amount of ambient heat getting in is enough to push the fluid beyond its comfort zone.

What confuses me slightly, is given the max temps the fluid is designed for, it would be hotter than the engine bay, so wouldn't a metal reservoir at that point be radiating heat from the fluid to the engine bay, as the fluid is hotter?

Anyway, so, yes, relocation? Any downsides beyond accessibility?

I was contemplating a water cooling system that would keep the fluid temp down until I get it fixed. Nothing special. Just a hose and a big bottle of water - A real slick setup.

Moving the reservoir may be a more sophisticated idea though

[rytaylor]

KMud said:

10 years/97k miles!? I got 8 years/35k miles from mine!

Yeah, its never been changed that I know of. 35k miles is good going - you must be a fan of rolling burnouts

[rytaylor]

New ls7 clutch, slave cylinder and spigot bearing fitted to the car and problem solved. Not exactly sure which was the cause of the gear selection trouble but the spigot was apparently in bad shape, so a good time to get it changed!

Thanks to Neil for sorting it all out. Clutch was much sharper on the drive home.