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MG MGB Technical - clutch grind

helo ive recently had a full engine rebuild including a new clutch but some times the clutch seems to grind and i can feel a vibtration .any ideas thanks daren
daren

Have you checked the clutch fluid level?
Have you checked the movement of the clutch fork?
Is it easier to shift if you pump the clutch pedal?
Did the shop where you had the work done offer any type of warranty?
Kimberly

thr clutch does not grind all the time ,seems more when the engine is hot ,i have no warranty thanks daz
daren

Worn pivot points.
Air in the hydraulic system.
Internally deteriorated flex line.
Leak in the hydraulic system.
Failing clutch master cylinder.
Kimberly

Mine was doing that when the release bearing was rubbing on the clutch cover. Eventually it wore right through and broke.

If the *gears* grind when attempting to select reverse that could be the things Kimberly mentions, but not if the grinding comes from the clutch itself i.e. it happens when you push the pedal down but the gear lever is left in neutral.
Paul Hunt 2

If a new clutch was fitted then is is unlikely it has worn though!

There is a common problem at the moment with the clutch release bearings - there are three batches of them out there - the first is OK and fits correctly with the two flat metal spring clips - the second is wider and has two holes drilled in the ends of the pivots and is used with a wire spring clip as per the very early cars - the third has no holes in the ends of the pivots but is the same width as the one that has the holes.

The last two CANNOT be fitted properly with the flat spring clips - the bearing binds in the fork.

I have now come across two cars with vibrating clutch pedals that have had incorrectly fitted release bearings - one was fitted with just one clip and the other fork end had been beaten over to stop the pivot falling out!!
Chris at Octarine Services

Lots of non-clutch-related stuff can do that. On take-off from a standstill, which just happens to be when your clutch gets the most use, the engine rocks in its mounts from the transfer of torque. It could be rocking just enough that it, the tranny, or the exhaust can touch the body when you're taking off. The vibrations that get transmitted when this happens feel very, very wrong - the body transfers vibrations incredibly well, so even a little contact and you will swear that something expensive is going on. Since your engine has just been out, my suspicion is that something's contacting the body, and a small adjustment/repositioning of either the motor mounts or the exhaust may do the trick.
sam

thank you daz
daren

Having replaced hundereds of clutches in the last 30 years I have come across this problem about 10 times.
The release bearing with the holes in the ends for the wire clips is for the 5./60 Hillmans etc.& others. The clutch fork on the B does not have the indents in the back for the wire clips. This release bearing shudder is coused by the bearing not being central to the release plate on the clutch cover. This can be because the bush & or pin a worn but in some cases the bearing is not central on the first motion shaft even when everything is tight. It seems as tho' some front gearbox covers are not machined correctly. The problem sometimes cures itself.
Garth.
Garth Bagnall

This thread was discussed between 26/03/2007 and 03/04/2007

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