W203 Brake vacuum pump oil leak.

Oldspanners

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While underneath the car cleaning the connectors to try and get get rid of the P0365 I noticed a slight oil leak and traced it back to the brake vacuum pump right at the back of the engine.
It's only two bolts to take out to replace the gasket and a small O ring which seems to be difficult to source.
The question is has anyone done this job as it looks like a real knuckle breaker and where did you buy the parts?
Thanks.
 
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Well, short story of long story. Found the seal on ebay waited three weeks for delivery which failed and then again. Eventually ordered from MB Newcastle arrived in 5 days.
Don't recommend trying this without a 1/4" swivel head ratchet and a 8mm socket rather than the torx which on my set is the first on the 3/8" drive as it's so close to the bulkhead. Press in the ring on the vacuum hose and remove from the pump and inlet manifold. Be careful when taking the two bolts out not to drop them down the back of the engine, the LHS one is between bolts securing the engine lifting eye and the RHS one even closer to the bulkhead. Don't move the drive lug as it engages in the end of the cam and you'll have trouble re-aligning it as it's all but impossible to see. The later type of pump uses a compression type gasket and needs a small O ring on the end of the drive.
Clean up the surfaces with some brake cleaner and refit the bolts with some blue Loktite not a chance of getting a torque wrench in so just nip them up.
In the end not too bad with the small swivel head ratchet, it takes a lot longer cleaning up the mess left by the leak down the back of the engine, over the bell housing and onto the under tray.
A few photo's that may or may not help, the last the most important.
 

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Oldspanners

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Had a look yesterday and found it still weeping, so took it off again, cleaned the mating surfaces and smeared some red RTV sealant around the area outside of the seal.
See how that goes.
 
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Oldspanners

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Had another go at fixing this annoying weep this morning. Looks like it's coming from between the cover and the body of the pump and as the gasket isn't available separately, the only one I can find is in a RKX rebuild kit about €45 delivered from USA, the only other option is a new pump at only €230.
Either option expensive for a rubber seal. So I removed it again, stripped the cover off, 5 torx 25 bolts cleaned up the faces and seal with acetone (note it is full of engine oil for lubrication) applied a thin bead of RTV gasket and torqued up the bolts to 10NM and reinstalled it.
See how this goes over the next few weeks when (if) we are released back on to the roads.
 
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I don't really want to say it but it looks like it's fixed.
No sign of any oil since March, so if your engine has an oil leak there I'd suggest a little RTV between the cover and the body of the pump first.
I note it only took me a year to come to this conclusion.:(
 

shotgun600

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10x man, you are saving my life right now with that info.
 

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10x, this week I will check in the local dealer for the seals. If the one for the pump - the big O seal, is not available, I will try to use high temp silicone for gaskets.
The ebay offer will be my alternative if nothing is available here.
 
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10x, this week I will check in the local dealer for the seals. If the one for the pump - the big O seal, is not available, I will try to use high temp silicone for gaskets.
The ebay offer will be my alternative if nothing is available here.
For about £17 you get all three the external, big and small internal and even an external for a later model pump.
 


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