can anyone help please oil leak
Moderator: martauto
can anyone help i have a oil leak when i jack the car up from the front it seems to be coming out from between the bellhousing and gearbox but i dont seem to be losing any fluids from the engine and it doesnt smell like gearbox oil
- Brianmoooore
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Fluid coming from there can be engine oil, gearbox oil, or, most likely, clutch fluid.
Check the level in the clutch reservoir.
Check the level in the clutch reservoir.
- Brianmoooore
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And your engine is?
- Brianmoooore
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Very likely. The M20 sump gasket gets very brittle with age, and tends to leak at the rear.willnz wrote:Could be the sump gasket has fractured at the rear of the motor and is dripping oil into the bellhousing.
There's an alloy piece that covers the gap between the sump at the rear and the bottom of the bellhousing, held on by a few bolts at right angles to another few bolts. Remove this, and you should be able to see where it's leaking.
Replacing the sump gasket on a M20 is not the easiest job in the world, because the oil pump sits down in the bowl of the sump, preventing the sump from being removed from the car without lifting the engine.
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The half moon seals are the rocker arm access seals not camshaft and it would never be the valve stem oil seals.Jindmahi wrote:The oil could be coming from camshaft seal (half-moon), or Valve stem seals which could be heavily worn hence oil leaking past the block.

The half moon seals would be my first change. Oil runs down the back of the head and leaks into the bell housing. Put a clean finger between the bulkhead and head and wipe the back of the casting. If it's wet then change them.
The sump gasket is long winded but not hard. Forget trying to do it by jacking the engine up high enough. Just support the engine from above and remove the and crossmember. It leaves a completely clear view of the sump for it to be removed.
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definately not valve stem oil seals... but agree with the half moon seals or sump gasket. with an outside bet of rear crankshaft seal..but that really is just a slight possibility
Only in the good lord we trust.. In everything else we check!!
1988 325i Tourer, Lowered, Deep Dish Alloys, Obc, Cruise Control, Heated Leather Sport Seats....
1988 325i Tourer, Lowered, Deep Dish Alloys, Obc, Cruise Control, Heated Leather Sport Seats....
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Not to hijack, so you can PM me if necessary... But could I get a little more info on this, I am planning on removing my sump to get the drain hole drilled and re-threaded. I have a new gasket ready to go in, but didn't know if the sump would be able to come out in situ or not... I need to remove the whole crossmember?B7 wrote: The sump gasket is long winded but not hard. Forget trying to do it by jacking the engine up high enough. Just support the engine from above and remove the and crossmember. It leaves a completely clear view of the sump for it to be removed.
Cheap & easy fix as well, I even managed to change them myself! Change the rocker cover gasket at the same timeB7 wrote:The half moon seals are the rocker arm access seals not camshaft and it would never be the valve stem oil seals.Jindmahi wrote:The oil could be coming from camshaft seal (half-moon), or Valve stem seals which could be heavily worn hence oil leaking past the block.![]()
The half moon seals would be my first change. Oil runs down the back of the head and leaks into the bell housing. Put a clean finger between the bulkhead and head and wipe the back of the casting. If it's wet then change them.

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- Brianmoooore
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Seems a little extreme for a sump gasket! Especially as the replacement will probably need the same parts.scott10 wrote:would proberly be best to get anouther engine as i can get a engine for £150