Clutch Drag Issues - Advice

Trying to cut a long and ongoing story short; new clutch kit June last year, now only done est.5000 miles, has started dragging the past month so that the gearbox is still turning with clutch fully depressed. No leaks, just been bled through with all new fluid and adjustment checked, have tried over-adjusting to try and get plate to clear but no joy. It gets worse as its driven longer/warms up, mainly diagnosed via LT77 straight cut reverse idler: cold start reverse can be selected with little resistance and grinding, one driven and warmed reverse cannot be selected without force and brutal grinding. Gearbox oil changed this year (correct ATF fluid) and level is correct.

Just looking for anyones experience or ideas on this, am planning on trying to renew clutch hydraulic cylinders and flexi piping (isnt expanding under pressure though) before it comes to splitting the box (extremely annoying as I paid a considerable bill for a new gearbox and clutch kit just over a year ago). Ive heard rivets and springs come loose, spigot bushes move, etc, but clutch operation is still the same and no noticeably wrong noises, I cant think why it would get worse with use or warming up and then be ok again when cold/been left.

Any help much appreciated, cheers.

don't split the box! It can only be a clutch problem, if there are no leaks it will more than likely be the master cylinder

May have worded that wrong typing on the missus' fiddly tablet, I meant dropping the box as a last resort to look at the clutch assembly if renewing the hydraulics draws a blank. Thanks for your post though Im hoping it may not come to that.

if the clutch has been ok for 5000 miles I'd be pretty confident its a hydraulic problem

I'd hope so but I just can't work it out as everything is working correctly, and it gets worse throughout a journey?

Don't know whether anyone can shed some light on another ongoing possibly related possibly not - thing. Accelerating in 1st then depressing clutch and coasting causes a scuffing/whining noise from the transmission tunnel area or a bit forward. Taking it out of first while its making the noise will cause it to stop. Can't say I've noticed it in any other gears.

you say youve adjusted master cylinder rod ?have you got correct slave fitted ,correct push rod ,could be poor clutch cover ,you might get away by lengthening push rod a few mm

If all hydraulics ok and cylinders good as per James suggestion, what was the condition of the splines that the clutch friction plate are on? if they were damaged maybe the friction plate cant move freely away from the flywheel when clutch pressure plate is released.

Yes James master cylinder was all adjusted correctly anyway, tried to over-adjust it temporarily to get clutch to clear but didn't work. Can't comment on whether its actually the correct slave or not but it was fine all up until the gearbox/clutch was changed and has been fine for a year after.

Steve - clutch was refitted with a reconditioned LT77 so I hope the input splines were OK!

Have you got any ideas on the noise while coasting with clutch down in 1st James? It must've started a while before the clutch dragging issues, but has also gotten worse then it was originally. Also why would the drag get worse as it's driven/warmed up then get better when left to cool again?

Thanks for the help.

is it only first not 2nd ?

Might have to do some more testing to be sure but I think it might also be present in second but less so, if that makes sense? As in less pronounced, quieter maybe?

It would be worse when warm due to thermal expansion. What make of clutch was it? Was the fork replaced as well? I know the r380 suffers more from the punch through problem than the lt77, but still a possibility. Maybe get hold if a bore scope to have a look internally before pulling it apart. Could also be the release bearing sticking on the guide tube if it wasn't lubricated properly or a worn tube wasn't replaced.
Start with the externals first is always the best bet. Don't forget to check the clutch hose as well, it could be swelling internally (used to be a problem on the marina as the hose ran close to the exhaust and expanded when the exhaust got hot).
There are lots of factors to consider when diagnosing clutch faults, and it's not always the clutch that is the problem (unless it's britpart, lol).
I work in the technical dept for LuK, so hear all sorts if clutch problems day in day out, 9 times out of 10 it's an external factor causing the problem.

Tom.JTC said:

Yes James master cylinder was all adjusted correctly anyway, tried to over-adjust it temporarily to get clutch to clear but didn't work. Can't comment on whether its actually the correct slave or not but it was fine all up until the gearbox/clutch was changed and has been fine for a year after.

Steve - clutch was refitted with a reconditioned LT77 so I hope the input splines were OK!

Have you got any ideas on the noise while coasting with clutch down in 1st James? It must've started a while before the clutch dragging issues, but has also gotten worse then it was originally. Also why would the drag get worse as it's driven/warmed up then get better when left to cool again?

Thanks for the help.

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theres less drag from box as it warms up which seems just the right amount for you to notice, end float on main shaft or layshaft or loose bearing race can cause gear noise

Of course, that makes sense. Just tried the gears on the journey back and it's most noticeable in 1st but also present in 2nd, though not after the shift, you have to engage the clutch and speed up a bit then depress and coast and it makes the same noise, but it is lesser. 3rd is the last gear I can hear it in. Is this a serious issue? It's an Ashcroft box which was new June 2012.

Have just ordered new slave, master and flexi-pipe so that'll fix/rule out all the hydraulics.

i think they need to be looking at box and replacing clutch at the same time

Thanks for your help James, I have spoken to Ashcrofts on several occasions although not much luck has come of it yet. Once I've changed all the hydraulics if the problem persists there won't be much left to argue. Thanks again.

presuming it is box which it does sound like then its a fault that needs looking at ,did they fit box and clutch ?

It certainly sounds like it, noise disappears as soon as box comes out of the gear, months ago when I first heard it thought it may be front axle but have checked bearings, and brakes, etc. Yes they fitted them both, though out of warranty by a few months now, got the message that gearbox problems will be looked at but clutch is only manufacturer warranty. Difficulty is trying to sort out the grounds of warranty rights without going all the way back to them as that's not really feasible right now. A right pain.

tricky buts theres not a lot can be done with box without removing and stripping it

Yeah, you've been a big help though James so thanks, hopefully it'll be sorted eventually without too many problems.