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Discussion Starter · #1 ·
Hi all,

I'm thinking about pulling the Valve Cover off because I've been told when I had the Turbo changed that the gasket was saturated in oil. Anyway, I can't seem to find any guides specifically on the M57n2 engine.. I've removed the Intake Manifold a few times so I'm fine until that point but not sure going forward once that's removed.

Also, I get blue smoke of the I let the car idle long enough so I believe it's the valve stem seals. With the Valve Cover removed is it possible to identify if the valve stem seals are allowing oil to pass?

And finally, I've seen a few videos online where people manage to remove the valve stem seals without removing the head, from what I've seen you move the piston to top dead centre and then use either string or compressed air to stop the valve from falling once the valve springs are removed with a compressor tool. However, I've not come across one that's been done on the m57n2 engine, and I've also been told by two garages it's not possible. Having looked through the process I'm just curious, what would make this engine any different that the others that would prevent the valve being removed with the head on?

Cheers
 

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The only engine I've personally changed stem seals on without removing the head is an old ford cvh as they have a single cam and rocker arms.

Most twin cam heads the cam is directly over the valve with the spring set down in the head so would make compressing it tricky. The cam would also need to be removed.
 

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What's the mileage? Cam cover gasket or valve stem seals are quite rare problems on these diesel engines. If you really need to remove the cam cover you first have to remove all the injectors too.
 

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As others have said it is unlikely to be the seals. Has the crank case breather valve been changed? Generally speaking the method you refer to with compressed air to change stem seals in site is done on petrol cars utilising the spark plug hole and where the cams are not directly over the valve.
Cheers
Jim
 

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Discussion Starter · #6 ·
Thanks for the reply mate, I think it does have a little puff on startup. I have seen on video where the guy mentions he has a special tool to compress the camshaft and ensure it perfectly aligns the bearings as well. And that's a shame about the valve stem seals, do you know if the timing chain is visible with the rocker cover off?
 

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Discussion Starter · #7 ·
Hi mate,

147k on the clock, as I say it does lose 1 litre of oil every month or so. If I remove the dipstick with the engine running there is blow-by, but the car only smokes if the cars left idling and from what I've read that would be the valve stem seals because if it was the rings it should be blowing smoke out the exhaust all of the time which it doesn't.
 

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Discussion Starter · #8 ·
As others have said it is unlikely to be the seals. Has the crank case breather valve been changed? Generally speaking the method you refer to with compressed air to change stem seals in site is done on petrol cars utilising the spark plug hole and where the cams are not directly over the valve.
Cheers
Jim
I've been told this many times as well when I've enquired on the phone about them being replaced, I have replaced the crankcase breather with one directly from BMW (No loo roll or Vortex in their) I'm not sure if the pcv built into the rocker cover could be blocked or something else.. I'm not really sure how to check to be honest. But when I had the turbo replaced I'm 90% sure he mentioned they tested the vacuum pressure or what ever and it was perfectly fine.

Unfortunately it is burning oil and bluish smoke is visible so it's either those valve stem seals or piston rings I believe.. me and my dad have always been sceptical though because despite the potential problems it has it runs absolutely fine and has loads of power but with the crankcase breather being replaced I'm not sure anything else could cause those symptoms?
 

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If it was rings it would blow out blue smoke under load.

Worn stem seals would allow oil to leak past into the chamber when the car is left for a period of time which would them burn off as blue smoke on start up.

Leaving the car to idle for a while, the intake is under a vacuum. It must be pulling it through from somewhere? I'd guess the turbo but that's new?
 

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Discussion Starter · #10 ·
If it was rings it would blow out blue smoke under load.

Worn stem seals would allow oil to leak past into the chamber when the car is left for a period of time which would them burn off as blue smoke on start up.

Leaving the car to idle for a while, the intake is under a vacuum. It must be pulling it through from somewhere? I'd guess the turbo but that's new?
Hi mate,

okay that's interesting to know, so while idling if blue smoke occurs that's being pulled from somewhere? The turbo was done at Best Turbos who specialise in BMW's and to be honest it used to smoke blue before the tubo died so the odds of it being pulled from the turbo are very slim. I'm just going to pop out now and video record the startup as the engine hasn't been running since last night as my alloy cracked -_-.

So anyway, is there any possibility that this oil burning could be caused by anything else that I haven't already checked? The turbo and Vortex have been replaced but at the time I had no idea how the breather worked so I literally popped it off and put the new one on.. I never did check anything like the holes when I pulled the breather off to see if they was blocked.. I don't know how to test if the crankcase ventilation built into the valve cover could be blocked and I have no idea of anything else I could test? The only reason I have any motivation to look for another source causing the loss is because of how well the car runs, no misfires, idles and starts fine, plenty of power.. just literally burning oil is the only symptom.
 

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Discussion Starter · #12 ·
To be honest, I've never seen an M57 engine with valve stem seal issues or a leaking rocker cover to be honest.

I'd say your blue smoke is turbo related. Did you check the intercooler for oil?
Is it possible to check of its the Turbo? Can i leave it to idle and then pull the pipe off the throttle body and place tissue over then give it a rev to see if oil blows through? And no I've not checked the intercooler for oil, I'll have to see how to do it and check.

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Is it possible to check of its the Turbo? Can i leave it to idle and then pull the pipe off the throttle body and place tissue over then give it a rev to see if oil blows through? And no I've not checked the intercooler for oil, I'll have to see how to do it and check.

Cheers
Did you ever get to the bottom of this issue mate?
 
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