Knocking noise in reverse

Post by **LouiseM** » Sun Jul 20, 2008 1:51 pm

Not sure of the technical term but my car has developed a knocking noise and is a bit 'shuddery' when I reverse it

The noise is coming from the rear of the car.

What's likely to be the problem? Prop shaft? UJ's? Easy to fix? Expensive etc?

I won't get a chance to look at it again before next weekend but if anyone can offer a suggestion as to what the problem might be I would be grateful.

Thanks,

Lou

Post by **MoggyTech** » Sun Jul 20, 2008 8:37 pm

It's clutch judder, and it's very common. All you can do is check the condition of the engine and gearbox mountings, check that the engine tie bar is fitted and adjusted correctly, check the gearbox steady wire is adjusted correctly. After that it's check the rear axle and springs are OK, and if after all that, it still does it, new clutch and release bearing.

Post by **LouiseM** » Sun Jul 20, 2008 9:55 pm

it's very common

I haven't had this problem on my 3 previous Minors though

Any idea why it would suddenly start being so noisy or is it just general wear?

But thanks for the advice. I think a look at my workshop manual is in order.

Post by **MoggyTech** » Sun Jul 20, 2008 10:04 pm

I should have said it's very common with the later type clutch used with the 1098 engine, the early type clutches didn't do it as much. The judder is actually axle tramp caused by the clutch snatching. Some times it's due to oil contamination on the clutch linings. This is usually from the rear crank scroll oil seal. Leaks here are usually due to worn main end bearings, or more common is poor engine breathing (crankcase ventilation).

Sometimes a smear of copper slip grease on the face of the thrust release bearing helps. This can be done with the gearbox in the car. There is a large rubber grommet on the LH side of the gearbox, which allows access to the thrust release bearing.

I had this judder on my car, and tried everything before changing the clutch, which fixed it. I replaced engine/gearbox mountings. Checked Prop UJ's and replaced all rear suspension bushes and spring rubber mounting pads.

Post by **bmcecosse** » Sun Jul 20, 2008 10:10 pm

Yes - likely to be clutch contamination. If the other checks MT suggests don't come up with anything - you could try putting the car in top gear with brakes hard on - rev up the engine and let the clutch out sharpish. If it stalls the engine right away then it's good - if it slips, then it's on it's last legs.