Clutch judder after fitting new diff

[Cam]

Quick question that I have been asked to post by our branch secretary.

He's recently changed his diff for a quieter one and while he was at it, he's changed the prop UJs as well.

The backlash in the new diff is significantly less than the old one.

Now he's complaining of judder on take-off in bottom gear & reverse whereas there was no judder previously (before he changed the diff/prop UJs).

I have asked about the engine steady and the gearbox steady cable already.

Oh and the car is a 1960 traveller with a 1098 engine and 1098 rear axle. Actually, he's replaced the whole axle for a 1098 one (which I gave him), as his old 'duff' one was the original 948 one.

Any ideas, or has anyone come across this before?

[brixtonmorris]

how old is the clutch?

[Cam]

From memory about 12 months to 2 years. But this has not been touched during the changeover.

[brixtonmorris]

i found clutch judder when the rivets on the clutch cut into the flywheel or clutch pressure plate, when when the g/box cable and tie bar were connected. may be that the lack of backlash has has made it more noticable. the clutch is not that old so i suppose that the question is how many miles? and does the morris spend its time in traffic?

[samheath100]

Have you got access ta a lathe, as my friend got clutch judder on his 1956 sunbeam. He put it in the lathe and took about 10 to 15 thow off, this seemed to cure the problem. Please note though that you cant really touch the clutch plate because any oil that gets onto it will just cause more clutch judder. And if you are going to wipe it clean with a substance then DONT use parafin. many people think that parafin is good for cleaning things like this. parafin or kerosine (depending on what you call it) contains a lot of oil so again this will cause clutch judder. I suppose the thing you could wipe it with is pannel wipe of some other de-greaser. hope this is of some use. sam

[salty_monk]

I would guess that some slack in the old stuff was helping to "iron" out the judder.
Normally this is associated with gearbox or engine mounts (& a hell of a lot of minors judder in reverse...), doesn't always mean they are shot either... Willie's judder got worse when he fitted new mounts!

[Cam]

The Morris in question does not do many miles as it's used to attend rallies only really.

Sam, the judder was not present before he changed the diff, and now it is, so I don't think that the clutch plate is the source of the problem, OR if it IS then it was masked by the play in the diff/prop and now it's apparent.

I think that is probably the cause. I'll ask to see if he's changed the engine mountings for new ones as I remember he's only recently (less than 12 months) changed his engine, but did not complain of judder at the time, so perhaps it was masked...

[turbominor]

dumb question i know but are the bolts holding the prop to the diff flange the right size and tight..

Had trouble with a wipping noise on emily when going from power to over run as the bolts i used we marginaly too thin and working loose..

[Cam]

I'll ask the question. Mind you, I would imagine he's re-used his old ones if they were OK... I'll mention it anyways...

[turbominor]

mine came off with a die grinder and chisel