changing rear main seal

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oze30
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Post Mon Jun 19, 2006 9:07 am

How hard is this to do?
Templ8e30
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Post Mon Jun 19, 2006 2:53 pm

Pretty hard

Sump off
Gearbox off
Clutch and flywheel off
New sump gasket
New seal carrier gasket
etc etc

If your leaking oil at the back of the engine I'd put money on it being the sump gasket rather than the seal, they seem to go in that area first for some reason.

Cheers,

Iain T
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oze30
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Post Mon Jun 19, 2006 3:04 pm

what if its gearbox oil?? Im leaking engine oil from the oil cooler o ring.. but the gearbox is leaking apparently. There's shed loads of oil and gunk under the gearbox, exhaust front box etc etc..

What could it be???
Templ8e30
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Post Mon Jun 19, 2006 5:20 pm

Rear gearbox seal ? or maybe front gearbox seal ?

Maybe even selector shaft seal.

Rear seal can be done on the car but the front one can't

Cheers,

Iain T
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oze30
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Post Mon Jun 19, 2006 7:17 pm

If it is the front seal.. would I be better off changing the whole gearbox?
Templ8e30
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Post Mon Jun 19, 2006 9:46 pm

It depends how good you are with the spanners, if you've taken the gearbox out ok then the front seal is relatively easy. The seal sits behind a circular plate held on with a few small bolts.

If the gearbox is otherwise ok then fit a new seal, if it's a bit noisy or generally suspect swap the box.

Cheers,

Iain T
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TouringMatt
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Post Mon Jun 19, 2006 10:01 pm

You'll know if its gearbox oil by the vile smell.

I was convinced my rear crank seal was gone, when i worked out there was an inspection cover that i could take off i decided to take a gander. Turned out it was as suggested above loose rear sump bolts, finger tight practically!

Carefully tightened them and added some seam sealer, did the job for now

I was leaving pools of oil everytime i parked and most the gearbox underside was covered in a oil/dirt/sludge mix, right back to the exhaust bracket - a reet old mess it were!

Worth checking out first before you worry yourself too much

Matt
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Brianmoooore
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Post Mon Jun 19, 2006 10:48 pm

Oil leaks from BMW engines are a system thoughtfully provided by BMW to prevent underbody corrosion.
oze30
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Post Tue Jun 20, 2006 10:31 am

Brianmoooore wrote:Oil leaks from BMW engines are a system thoughtfully provided by BMW to prevent underbody corrosion.

You'd think that, but they still managed to corode my fuel tank