20 replies to this topic

[RooBoonix]

Hi,

 

I have searched alot, but I can't find anything which I haven't tried yet without taking the clutch to bits..

 

Recently rebuilt my engine, runs great but the clutch is dragging quite badly. I can't select gears from stationary without turning the engine off and starting in gear, with the clutch down. This alone shows that the clutch is partially disengaging. It's a 1275 SPi by the way, clutch plate and pressure plate have been replaced with the minispares injection kit, along with release bearing and o-ring. I am getting full movement on the clutch arm, set at 6.5mm throwout gap. 

 

I have read online, only a couple of people have had this, that the pressure plate can be faulty and not releasing fully. I still have my old pressure plate, which still has the machining grooves on the clutch face, it's hardly even worn. I am tempted to try and fit this and see how I go. Has anyone else had an issue with verto pressure plate being too "tight"?

 

Clutch arm has been replaced, as have all the clevis pins. Slave is the correct kind and like I said, I am getting full travel on the clutch plunger.

 

London to Brighton is on Sunday, and I'm going to that. I am tempted to leave it for now, as it is driveable, and sort it out after because I don't want to miss it. How difficult is it removing the clutch assembly with the engine in the car? I've got all the tools to do it, but I am reluctant to take the engine out with it being injection theres alot to remove and I don't really have time!

 

Cheers,

Cam.

Edited by RooBoonix, 16 May 2017 - 11:56 AM.

[Northernpower]

You seem to have covered most of the bases, did you check the primary gear end float? The following is an extract from a Keith Calver article: Too much end float and clutch disengagement is adversely affected, the gear floating up and down the crankshaft in unison with the clutch plate. The result is a graunching gear change since the plate isn't clearing the flywheel and pressure plate surfaces fully

[RooBoonix]

Yep. Got it best I could using the thickest thrust washer available. Even with a NOS gear.. It was 6 thou from memory.

[Northernpower]

Yep. Got it best I could using the thickest thrust washer available. Even with a NOS gear.. It was 6 thou from memory.

Was there any wear on the c washer? if there is, you can turn it round to gain a couple of thou.

[RooBoonix]

Yep. Got it best I could using the thickest thrust washer available. Even with a NOS gear.. It was 6 thou from memory.

Was there any wear on the c washer? if there is, you can turn it round to gain a couple of thou.

Done that, and I bought a new C-washer backer made by minispares which is made a couple thou thicker. I can't see the end float being the issue as it's not so severe to cause that surely. The drag will literally move the car like you've got your foot 1/3 of the way up on the clutch.

I've got my suspicions on the pressure plate to be honest but I just thought I'd post to see if anyone else had *any* other ideas because without dismantling a whole lot I'm stumped!

[Northernpower]

Yep. Got it best I could using the thickest thrust washer available. Even with a NOS gear.. It was 6 thou from memory.

Was there any wear on the c washer? if there is, you can turn it round to gain a couple of thou.

Done that, and I bought a new C-washer backer made by minispares which is made a couple thou thicker. I can't see the end float being the issue as it's not so severe to cause that surely. The drag will literally move the car like you've got your foot 1/3 of the way up on the clutch.

I've got my suspicions on the pressure plate to be honest but I just thought I'd post to see if anyone else had *any* other ideas because without dismantling a whole lot I'm stumped!

I would agree with you. I only made my suggestion because you seem to have covered all the obvious choices. Clutching at straws and thinking outside the box (no pun intended) you have filled it with a quality oil?

[RooBoonix]

Yep. Got it best I could using the thickest thrust washer available. Even with a NOS gear.. It was 6 thou from memory.

Was there any wear on the c washer? if there is, you can turn it round to gain a couple of thou.

Done that, and I bought a new C-washer backer made by minispares which is made a couple thou thicker. I can't see the end float being the issue as it's not so severe to cause that surely. The drag will literally move the car like you've got your foot 1/3 of the way up on the clutch.

I've got my suspicions on the pressure plate to be honest but I just thought I'd post to see if anyone else had *any* other ideas because without dismantling a whole lot I'm stumped!

I would agree with you. I only made my suggestion because you seem to have covered all the obvious choices. Clutching at straws and thinking outside the box (no pun intended) you have filled it with a quality oil?

No worries, I appreciate the comment. I didn't actually realise that end float here could affect clutch engagement in such a way. The primary gear was also in a hot oil bath at around 80-100c for 6-8 hours (lost count might have even been longer than that) to get the deva bushes nicely oiled.

It is on its first fill of Minispares own brand 20w50. I thought I'd give it a go as it seems to have the right amount of ZDDP and actually seems like a nice oil, It's very sticky! I'll be changing this in the next 20-30 miles.

Edited by RooBoonix, 16 May 2017 - 05:38 PM.

[Northernpower]

Yes I use MiniSpares own brand and it works very well. I assume the plate slid on the primary gear spines without any problems?

[RooBoonix]

Absolutely fine nice and smooth, all fitted the right way round and the pressure plate bolts were left loose so the plate could centre properly and then tightened up with threadlock to the torque setting (18lb ft from memory, I made sure I didn't get any torque values mixed up as I know there have been issues with the torque value between the boss and pressure plate).

[Northernpower]

How difficult is it removing the clutch assembly with the engine in the car? I've got all the tools to do it, but I am reluctant to take the engine out with it being injection theres alot to remove and I don't really have time!
 
Cheers,
Cam.

It's not difficult changing it in the car, just time consuming. I've just changed my drop gears in the car so a clutch will be much easier.

[Dusky]

It's been a while since I fitted a verto flywheel. Is it possible for the C washer to get pinched by the pressure plate boss ? (Was my problem on my pre verto)

You can test the flywheel assembly on the bench to see if it disengages.
Wonder if too big of a crank float could cause this.

[Cooperman]

I have posted a 'Clutch Drag Fault Finder' on here. Do a search as it gives every possible cause for clutch drag and the order in which you need to check each possible cause.

 

Personally I wouldn't drive a Mini with clutch drag for fear of the possible further damage it can cause.

[RooBoonix]

It's been a while since I fitted a verto flywheel. Is it possible for the C washer to get pinched by the pressure plate boss ? (Was my problem on my pre verto)

You can test the flywheel assembly on the bench to see if it disengages.
Wonder if too big of a crank float could cause this.

I think it's possible, but it's the standard boss and I only lapped it onto the crank lightly. I won't disregard it though. The crank end float I set to 2thou when I built the engine.

[RooBoonix]

I've decided I might try and get the assembly off, even if I do it in several sessions just to get it done as it's a pain and like Cooperman has stated the possible damage I don't want. And yes Pete, I've seen the fault finder it's a great help.

Edited by RooBoonix, 16 May 2017 - 07:36 PM.

[Cooperman]

Work through the fault finder very methodically. You might find it is just a hydraulic problem which can be fixed in an hour or so.