OM642 PCV Valve Question
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MBWorld Fanatic!
Joined: May 2015
Posts: 1,932
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From: Allentown, PA
'08 GL 320 CDI
I finished up (finally... life gets in the way!) the catch can install with the new PCV valve. I'll do another post about that. But... 007... from what I've learned through this process the build up you see is likely due to the crankcase emissions mixing with the EGR that causes the heavy tar. So it's not really one or the other's fault - it's the mixture of the two.
Over the summer, my intake manifolds had to be replaced (well, the swirl motors specifically... but I just got everything new since the price was right). They were sludged up like yours - not quite as bad, though. However, when I replaced the PCV valve, I opened it up and the membrane inside it was torn - allowing more crankcase gas into the turbo and the rest of the intake system. You might want to remove your PCV and pop the top on it and check it out.
Over the summer, my intake manifolds had to be replaced (well, the swirl motors specifically... but I just got everything new since the price was right). They were sludged up like yours - not quite as bad, though. However, when I replaced the PCV valve, I opened it up and the membrane inside it was torn - allowing more crankcase gas into the turbo and the rest of the intake system. You might want to remove your PCV and pop the top on it and check it out.
Super Member
Joined: Aug 2008
Posts: 528
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From: Chicago IL
X166 gls450 2017
I finished up (finally... life gets in the way!) the catch can install with the new PCV valve. I'll do another post about that. But... 007... from what I've learned through this process the build up you see is likely due to the crankcase emissions mixing with the EGR that causes the heavy tar. So it's not really one or the other's fault - it's the mixture of the two.
Over the summer, my intake manifolds had to be replaced (well, the swirl motors specifically... but I just got everything new since the price was right). They were sludged up like yours - not quite as bad, though. However, when I replaced the PCV valve, I opened it up and the membrane inside it was torn - allowing more crankcase gas into the turbo and the rest of the intake system. You might want to remove your PCV and pop the top on it and check it out.
Over the summer, my intake manifolds had to be replaced (well, the swirl motors specifically... but I just got everything new since the price was right). They were sludged up like yours - not quite as bad, though. However, when I replaced the PCV valve, I opened it up and the membrane inside it was torn - allowing more crankcase gas into the turbo and the rest of the intake system. You might want to remove your PCV and pop the top on it and check it out.
Thread Starter
MBWorld Fanatic!
Joined: May 2015
Posts: 1,932
Likes: 291
From: Allentown, PA
'08 GL 320 CDI
Yeah, I came across that CB Engineering plug. I contemplated doing that, but your point about pressure building up was the same one I had issues with, too. The only way I could think of to take care of the pressure thing is to vent the PCV to atmosphere. I thought about doing that - but still using the PV 200 since that supposedly cleans up the air real well. But instead of routing it back to the turbo, route it to the atmosphere (or to the remote oil can reservoir I mentioned above, first) - maybe use one of those little PCV filters to avoid dust getting back into the engine. But I think the filter in the PV 200 would take care of that, too.
Oh... the o-ring on the PCV valve stem (the part that inserts into the engine) is another possible source of an oil leak - but that's easy enough to spot given it's location. Just throwing that out there as another source of an oil leak to look at.
Oh... the o-ring on the PCV valve stem (the part that inserts into the engine) is another possible source of an oil leak - but that's easy enough to spot given it's location. Just throwing that out there as another source of an oil leak to look at.
