Clutch problems diagnosis required

[Dearg1275]

Frustration Frustration Frustration,

I’ve just finish off the revamp of my Mk2 works replica and needed to get it out of the workshop to give it a wash but...

When I press the clutch it stalls the engine and the clutch does not disengage. This was working fine before the engine rebuild and the only thing I have altered is a new clutch plate and completely working through and eliminating the wear in the clutch linkages. It should be perfect.

Is this what I suspect, that the clutch plate is jamming on the primary gear splines? Or is there anything else that could cause these symptoms.

D

[AndyPen]

Did you clean out the oilway holes in the primary gear as it’s unlikely if you did?

[Southwest]

viewtopic.php?f=3&t=19894&p=165186&hili ... in#p165186

[Dearg1275]

Did you clean out the oilway holes in the primary gear as it’s unlikely if you did?

Not specifically. It was washed and blown through and checked for free rotation on the crankshaft. How would this affect the engine being stalled and the clutch not disengaging?

[bwaminispeed]

Not what you want to hear, but, the crank thrust washers are possibly installed backwards.....

Have seen this issue twice now (no, not me), and, both times it was thrust washers put in backwards.....

[Dearg1275]

Despite being aware of how things should go together we can all make careless mistakes. Nagging doubt is also a terrible thing.

The engine is coming out tomorrow rather than mess about not knowing.

I still can’t see why this should prevent the clutch disengaging if I have enough throw to stall the engine or perhaps there are two issues here. Stuff happens.

D

[Oneball]

Ive had an engine eat through the thrusts the first time the clutch was pressed due to a worn surface on the crank and I’ve also had thrusts so worn that the clutch won’t disengage and the engine will stall. Did you check the crank for end play?

[Dearg1275]

Ive had an engine eat through the thrusts the first time the clutch was pressed due to a worn surface on the crank and I’ve also had thrusts so worn that the clutch won’t disengage and the engine will stall. Did you check the crank for end play?

Yep, had the dial gauge on it and it was fine. I guess I’ll find out if I’ve screwed up tomorrow.

D

[AndyPen]

Did you clean out the oilway holes in the primary gear as it’s unlikely if you did?

Not specifically. It was washed and blown through and checked for free rotation on the crankshaft. How would this affect the engine being stalled and the clutch not disengaging?

I recently stripped a clutch with very bad drag that someone had just rebuilt. Turned out the primary gear was stuck on the crank as the oilways were clogged. Easy to clean out with a bit of wire as you probably know.

Hope you find something as easy to resolve

[Minigman]

Lightened flywheel and heavy diaphragm?

I’ve had recent issues with my set up. I raised the idle to prevent the stalling and it’s bedded in now.

Could be thrust washers though sadly.

[Polarsilver]

Just another Clutch Story.. Purchased a car some years ago & on Holiday in Scotland the clutch started to slip.. well the Clutch was all ok before.. got home & took this 1275 S Engine & Box out & let it stand for the next 5 years.. so this week i strip out the Clutch .. I find the clutch fault ..previous owner & his 1980,s engine builder had machined the Flywheel thinner maybe to lighten it who knows .. he then refitted the Standard length 3off Bolts that hold those oblong spring Plates onto the Flywheel .. unfortunate for me those 3 Bolts are now too long with the Flywheel Machined then with some Clutch Friction Plate wear down by just enough ..Those 3x Bolts touch the backplate with just a light touch yet just enough to cause Clutch Slip because the Friction Plate does not then fully clamp tight
Sorry this is not the same issue that you have .. but shows that all components need to be correct when assembled or we pay for mistakes later on.

[bmcman.ie]

Thats exactly the same problem i had with my 1071!

[Dearg1275]

Well put me in the naughty corner. Yes, it was one of the trust washers. The upper one in the block and it would be on the side that takes the clutch thrust. What a pr——t.

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Yes there is some damage on the crankshaft thrust face but not too horrible. I’m tempted to put new thrusts in and run with it. On the other hand perhaps another complete strip and clear the oil galleries is the pukka thing to do and have the thrust face redone. Sleep on it I think and avoid impatience.

D

[AndyPen]

At least you now know - sleep well and maybe leave it for more than one night too