Hmm.. Trackday excess has resulted in problem

picopro19k78 · Jun 9, 2009

Hi all. went on first trackday saturday and had brilliant day. However, I now have an intermittant knocking noise from rear passenger wheel area. Doesn't get worse on cornering, but when occuring gets quicker with forward speed. Haben't had a chance to take wheels off yet but quick inspection appears nothing is loose etc.
The driveshaft on this side seems to slide in and out much easier than the driver side, ie more lateral movement. There doesn't seem to be any excessive play in any other plane.
Before I start to a) cry and b) strip the whole area, any suggestions. Could it be a failing wheel bearing? CV joint?
Thanks [&o][&o]

wjk_glynn · Jun 10, 2009

You never know, it might be a broken exhaust hanger... its worth a look.

Karl.

zcacogp · Jun 10, 2009

Intermittant knocking noises are a pain in the bum to trace. Best place to start is with the whole lot in the air and you applying Mk1 eyeball to the scene of the crime.

Look for loose exhaust hanger (as mentioned), loose brake pads (more relevant for those with the Brembo brakes) and check the backplate isn't in tatters.

CV - possible. Snag is that the only sure-fire way of diagnosing this is to change it (or dismantle the old one and look for wear.) They aren't *that* expensive and are quite easy to change.

Oli.

Diver944 · Jun 10, 2009

Check that the brake disk backing plate hasn't rusted through around one of the 3 securing bolts. This causes them to bang and clatter around much noisier than you'd expect

picopro19k78 · Jun 13, 2009

Thanks Guys. Got it in the air and no noise on turning the wheel. If you twist the driveshaft as if opening a throttle on a motorbike with moderate force, the drivers side doesn't have movement the passenger side does, so suspect the driveshaft.
Have been quoted £30+VAT for a complete 2ndhand unit from P & H.
Think I'll give it a whirl for 30 quid.
Thanks again

zcacogp · Jun 13, 2009

OK .... second-hand wear parts always strike me as an odd economy, but I hope it solves your problem.

Take care with removing the CV bolts. Use the proper tool and make sure it is fully inserted before applying any torque. If you strip the splines you are into a whole world of problems.

Oli.

picopro19k78 · Jun 14, 2009

Cheers Oli. I would strip down and rebuild but where would I get the parts? Ive seen new driveshafts from Berlyn at 200 quids.
I guess I would need 2 CV boots and the bearings? Seen some CV Boots on fleabay for £2.95!"!
I suspect as is is only a very small amount of play, its unlikely to let go any time soon?

zcacogp · Jun 14, 2009

I presume that by "driveshaft" you mean the driveshaft and CV joints at the ends.

The shaft itself doesn't wear, so you'd replace the CV's.

I paid around £45 each for CV's from Frazerpart, including delivery, about two years ago. That included new bolts, boots, joints, grease (but I supplemented it with some extra) etc etc etc.

While a second-hand 'driveshaft' (inc CV's) may be in great working order, you have no idea how much life there is left in it, and it could be no better (and indeed even worse) than the one you are replacing. Which would of coruse mean £30 and a reasonable chunk of time wasted.

Oli.