Warped Rocker/Valve Cover F30

davethefish · 12-10-2019, 06:38 PM

Anyone had thier rocker/valve cover leaking?

got back from the dealers earlier,
took my car (2012 320i) in with oil leak that was dripping on the catalytic converter and smoking off intermitently.
usually after driving a good distance and/or after braking downhill, or from speed on the motorway.

a temporary fix i discovered by chance was removing the engine oil cap and putting it back on it pretty much stopped it from leaking for a short while...?
not sure why...
but i was wondering if it was likely that it was a clogged or blocked PCV causing issues possibly over pressurising the cheap and nasty plastic valve cover?

dealers diagnosed a warped rocker cover and replaced it
(thankfully i bought the extended warantee) which covered the majority of it.
and i believe the PCV is integral to the cover?

Eddamoo · 12-12-2019, 06:58 AM

Yeah sounds like a PCV issue - The high induction vacuum of overrun should be scavenging the Crankcase pressure, but mustn't be working properly. Taking off the Oil Cap vents this to atmosphere so will no longer be pressurised. Its been a common BMW issue for decades now - my Z4 was terrible and it drank oil until i fitted another breather.

When you take the oil cap off, you should feel a very slight sucking with the engine at idle. With a broken PCV you'll either feel nothing or slight blowing (caused from blow-by).

It seems as though you like modding - a catch can will solve your issues

davethefish · 12-12-2019, 09:54 AM

Thanks for the reply,
currently googling 'catch cans'...

.
.
.

They look like a good idea, to prevent carbon build up on valve stems.
will look into adding one of those...

this video helped me understand the reasons fo one.

https://www.youtube.com/watch?time_c...ature=emb_logo

12-10-2019, 06:38 PM	#1
davethefish Captain 131 Rep 664 Posts Drives: 2012 F30 320i Sport Join Date: Oct 2011 Location: Bedworth iTrader: (0)	Warped Rocker/Valve Cover F30 Anyone had thier rocker/valve cover leaking? got back from the dealers earlier, took my car (2012 320i) in with oil leak that was dripping on the catalytic converter and smoking off intermitently. usually after driving a good distance and/or after braking downhill, or from speed on the motorway. a temporary fix i discovered by chance was removing the engine oil cap and putting it back on it pretty much stopped it from leaking for a short while...? not sure why... but i was wondering if it was likely that it was a clogged or blocked PCV causing issues possibly over pressurising the cheap and nasty plastic valve cover? dealers diagnosed a warped rocker cover and replaced it (thankfully i bought the extended warantee) which covered the majority of it. and i believe the PCV is integral to the cover? __________________ MOD's/DIY list Bonnet Badge Repacement, LED Door Sills, 35%VLT Window Tinting, 442m alloys, Stainless Steel Pedals, Front and Rear Disk Replacement, GTechniq C1 Detail, Gladen HIFI upgrade, LED DRL's, 90mm Stainless Tailpipe, Complete Leather Reupholstery.
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12-12-2019, 06:58 AM	#2
Eddamoo Captain 390 Rep 808 Posts Drives: BMW 430dX Join Date: Apr 2018 Location: Sheffield, England iTrader: (0)	Yeah sounds like a PCV issue - The high induction vacuum of overrun should be scavenging the Crankcase pressure, but mustn't be working properly. Taking off the Oil Cap vents this to atmosphere so will no longer be pressurised. Its been a common BMW issue for decades now - my Z4 was terrible and it drank oil until i fitted another breather. When you take the oil cap off, you should feel a very slight sucking with the engine at idle. With a broken PCV you'll either feel nothing or slight blowing (caused from blow-by). It seems as though you like modding - a catch can will solve your issues
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12-12-2019, 09:54 AM	#3
davethefish Captain 131 Rep 664 Posts Drives: 2012 F30 320i Sport Join Date: Oct 2011 Location: Bedworth iTrader: (0)	Thanks for the reply, currently googling 'catch cans'... . . . They look like a good idea, to prevent carbon build up on valve stems. will look into adding one of those... this video helped me understand the reasons fo one. https://www.youtube.com/watch?time_c...ature=emb_logo __________________ MOD's/DIY list Bonnet Badge Repacement, LED Door Sills, 35%VLT Window Tinting, 442m alloys, Stainless Steel Pedals, Front and Rear Disk Replacement, GTechniq C1 Detail, Gladen HIFI upgrade, LED DRL's, 90mm Stainless Tailpipe, Complete Leather Reupholstery.
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