Strange gearbox/clutch problem (V8/LT77)
Discussion
Well I think I'm getting there at last. The new master is back on but was a b'stard to bleed. I ended up bleeding the master on its own then back-bleeding from the slave to flush the air back up the pipe. It seemed to work but the action was too low so I have just adjusted the pushrod from the pedal to the master to bring the bite point a bit higher, I'll report more tomorrow after another drive.
P.S. I whinged on ebay to Wilco direct for their change in supply and got a fiver refund - result!!!
P.S. I whinged on ebay to Wilco direct for their change in supply and got a fiver refund - result!!!
Edited by adam quantrill on Monday 5th March 21:18
So - the plot thickens. I now have excellent clutch action, bite point is about halfway through pedal travel, there is a good 3 inches further to press down on the clutch after disengaging, and the pedal feels nice and firm, not spongy.
So I reckon the clutch is working fine.
HOWEVER - the gearbox problems remain. I have taken to double-declutching to get gear changes accomplished.
There is fresh Mobil 1 in there and Molyslip too. I have done around 80 miles with the Moly in so far.
Sometimes I forget to double-declutch and it works without crunching, sometimes it doesn't. Sometimes even with the double-declutch it won't change into the next gear especially going from 4th to 5th after a good booting.
So - what to do next? Are the syncro's shagged (partly or totally?) Can I look inside the box through the oil hole and inspect anything?
So I reckon the clutch is working fine.
HOWEVER - the gearbox problems remain. I have taken to double-declutching to get gear changes accomplished.
There is fresh Mobil 1 in there and Molyslip too. I have done around 80 miles with the Moly in so far.
Sometimes I forget to double-declutch and it works without crunching, sometimes it doesn't. Sometimes even with the double-declutch it won't change into the next gear especially going from 4th to 5th after a good booting.
So - what to do next? Are the syncro's shagged (partly or totally?) Can I look inside the box through the oil hole and inspect anything?
When a box went on my SD1, it made grinding and clattering noises in neutral with the clutch engaged a couple of weeks before that.
Took it apart and a bearing had gone big time on the lay shaft and the gears were worn as the meshing of them was way out of their tolerances.
All this happened a long time ago and can't recall if changing gears was an issue....
When it is still reasonable quiet in neutral, there is still hope that the mobil and moly can do there stuff and give it a longer life.
Perhaps it is an issue with the gear selecting mechanism only, and as you know to have a look or fix that, the box has to be taken apart.
Hopefully it is not the case.
Rob
Took it apart and a bearing had gone big time on the lay shaft and the gears were worn as the meshing of them was way out of their tolerances.
All this happened a long time ago and can't recall if changing gears was an issue....
When it is still reasonable quiet in neutral, there is still hope that the mobil and moly can do there stuff and give it a longer life.
Perhaps it is an issue with the gear selecting mechanism only, and as you know to have a look or fix that, the box has to be taken apart.
Hopefully it is not the case.
Rob
350zwelgje said:
Perhaps it is an issue with the gear selecting mechanism only, and as you know to have a look or fix that, the box has to be taken apart.
Hopefully it is not the case.
I know you already inspected the remote bushes as OK, but before you strip out the box, two things.Hopefully it is not the case.
- Recheck the natural alignment of the remote shaft and its freedom to move
- Give the oil/moly changes a little more time, I recall my improvements were progressive over 2/300 miles. Good Luck.
Yes the remote selector is solid - the "lift up the stick" method of diagnosing shows no play at all.
The box will stay in as it's still driveable - until it either fails or the Moly does its work. I have anpother box in reserve in case it fails.
I know what you mean regarding the layshaft bearings and usually another symptom of that is popping out of gear under power, but that hasnt happened, so far.
The box will stay in as it's still driveable - until it either fails or the Moly does its work. I have anpother box in reserve in case it fails.
I know what you mean regarding the layshaft bearings and usually another symptom of that is popping out of gear under power, but that hasnt happened, so far.
adam quantrill said:
the remote selector is solid - the "lift up the stick" method of diagnosing shows no play at all.
For all the time I owned my (LT77) car, I've been aware that the remote has had just a little bit of "give" in it and thought this was the purpose of the rubber mountings.When poly suspension bushes became an unfortunate rage and lots of owners changed over, gaining improved road-holding at the expense of creature comforts and rattling denture repairs, I'm sure someone warned me not to fit poly bushes to the gearbox remote because they were less resilient.
Perhaps my memory is playing tricks as its all a very long time ago since I replaced the remote bushes with OE items, tho', and the original notchyness and downright stubborn gear changes did not go away after I changed them.
It was only later when that effort clearly failed that I looked for desperate solutions.
Well so far I still have excellent clutch action - the pedal is adlusted deliberately high to maximise the throw.
On the gearchange front I still had some crunching and occasional stuck gears so not completely solved, I think the flush'n'fill did help but so far the moly hasn't cured all.
I have a spare broken box (or two - yes I get through them!) to play with so I may take the end off and look inside to see what I can see through the oil fill hole - in case an endoscope style inspection would reveal any internal faults.
So it's keep driving it until it either improves or goes bang. Except I can't 'cos of the water pump (see other thread).
On the gearchange front I still had some crunching and occasional stuck gears so not completely solved, I think the flush'n'fill did help but so far the moly hasn't cured all.
I have a spare broken box (or two - yes I get through them!) to play with so I may take the end off and look inside to see what I can see through the oil fill hole - in case an endoscope style inspection would reveal any internal faults.
So it's keep driving it until it either improves or goes bang. Except I can't 'cos of the water pump (see other thread).
Well I put another hundred miles of so on it this week, but in all honesty, it feels like it's getting worse if anything, occasional vibrations coming from the gearbox (you can feel them through the gearstick under load at certain rpms), the stuck in gear phenomenon is just as bad, if not worse. I feel that it's on its way out so I will be preparing the replacement for an onslaught of 320 bhp...
adam quantrill said:
Well I put another hundred miles of so on it this week, but in all honesty, it feels like it's getting worse if anything, occasional vibrations coming from the gearbox (you can feel them through the gearstick under load at certain rpms), the stuck in gear phenomenon is just as bad, if not worse. I feel that it's on its way out so I will be preparing the replacement for an onslaught of 320 bhp...
Maybe time to fit a T5.Well it is getting slightly worse.
Latest symptoms are that occasionally it will refuse to go into any gear unless the engine is stopped. Also if doing > 3k rpm (say around 70 in 4th) then when you depress the clutch it still seems engaged.
So I think the fault is that the clutch is dragging when the revs are up - a strange one indeed. I have PM'ed Steve to borrow his endoscope.
Latest symptoms are that occasionally it will refuse to go into any gear unless the engine is stopped. Also if doing > 3k rpm (say around 70 in 4th) then when you depress the clutch it still seems engaged.
So I think the fault is that the clutch is dragging when the revs are up - a strange one indeed. I have PM'ed Steve to borrow his endoscope.
I'm of the opinion that the only reason the remote was mounted on rubbers was because the SD1 was supposed to be an executive car and a buzzy gearshift would have given away the agricultural bits under the Wilton carpet. Hardly matters in a plastic open-top sports car.
Without reading the entire thread I'd speculate on something daft like the release arm is bending over time, or the release bearing carrier is disintegrating... or the gearbox is knackered
Without reading the entire thread I'd speculate on something daft like the release arm is bending over time, or the release bearing carrier is disintegrating... or the gearbox is knackered
Well whatever has had it, it's gone now because I can't select any gear without the engine stopped.
The clutch bite point still seems quite reasonable but it must be dragging somewhere.
I shall try the new slave cylinder I have in stock as it's a simple changeover - nothing much to lose if it doesn't work out. And I'll have a look through the hole to see what I can see.
Clutch slave replaced - new stock would not fit (different thread) but I had an old one off my white Tiv hanging about (the one you saw Leigh) which cleaned up and went on fine. Good news is the master now bleeds properly and easily. Bad new is the problem is exactly the same. Nothing much could be seen through the slave hole but the pushrod/arm felt find and normal when pulled and pushed.
The clutch bite point still seems quite reasonable but it must be dragging somewhere.
I shall try the new slave cylinder I have in stock as it's a simple changeover - nothing much to lose if it doesn't work out. And I'll have a look through the hole to see what I can see.
Clutch slave replaced - new stock would not fit (different thread) but I had an old one off my white Tiv hanging about (the one you saw Leigh) which cleaned up and went on fine. Good news is the master now bleeds properly and easily. Bad new is the problem is exactly the same. Nothing much could be seen through the slave hole but the pushrod/arm felt find and normal when pulled and pushed.
Edited by adam quantrill on Wednesday 2nd May 12:27
Don't think so, but thanks for the ideas, keep them coming. What does work:
1. All gears will engage with the engine stopped. The car will drive too.
2. Clutch has a definite good bite point and loads of travel either side.
3. You can start it in gear with your foot on the clutch, then let foot off and the car will move.
4. No noises from release bearing.
1. All gears will engage with the engine stopped. The car will drive too.
2. Clutch has a definite good bite point and loads of travel either side.
3. You can start it in gear with your foot on the clutch, then let foot off and the car will move.
4. No noises from release bearing.
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