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318 engine pcv valve problem


Well-Known Member
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9:02 AM
Jan 15, 2016
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I have a 318 engine that was rebuilt it now has 50,000 miles on it, I have the occasional oil on the outside of the pcv valve line after a hard drive about 80 mph, it only occurs a few times in the last 1200 miles and just started the last two years after driving 50k plus on this motor, please advise any one? there was some oil residue in the drivers side tail pipe it has duel exhaust, plugs are clean and no oil residue on them after driving.???
Can you post pictures of both valve covers? Shake the PCV valve to make sure that the 'pellet' inside is free. Check the air filter to make sure that the opposite side V/C cap has free access to filtered air, and lastly, make sure that the PCV valve is the correct one for your motor. If none of this works, try driving 70 mph. lol.
Thanks, i did change it after it occured the first time, it was bad, forgot all about how old it was, I have new chrysler valve on there, rattles well air goes through, both valve covers wre just off and checked the baffle, proper suction through the oil fill cover when the engine is running, so I think it may have been the high speed, not too sure will check again when I can drive it in april, right now its winter here in mass. It only did it about 3 times, but never on a long highway trip, very strange, must be something in the valve just hung up maybe I will tryanother on, thanks! for reading. I will post a pic of my engine soon.
Be sure to also check the grommet. They do have a tendency to get hard and brittle after time.
I changed the oil in October for the year, it seems it was over filled at least 1/2 Qt. this could of been the problem, I drained at least a half if not more, it is just below the fill mark on the stick, maybe it is just an oil change I did not do well... The grommet was just changed last year 1200 miles, valve fits tight,

would over fill do this in any engine??
Over fill could cause it, also make sure the breather cap on the other side is clear, and the line for the PCV and where it connects to the manifold are also clear!
Hi, My 318 was blowing out rear intake to block seal.
Found out the oil breather was a sealed unit. Replaced it with one that has holes around bottom of flange. Problem went away.
The breather should have open holes or should be vented to the air cleaner via a hose to pickup gasses. also, its interesting the mention of the grommet causing the problem, which I could see if it were cracked. Just an fyi, I am using both the pcv and breather grommets that are original to my engine, and so far, no leaking. They are a bit stiff, but still providing a good seal, and I don't have any oil problems, but I certainly will keep an eye on them to see if it ever develops.
my breather is stock factory original works fine, I think it was too much oil. I will keep checking and keep everyone posted...
Well it seems that the oil around the PCV valve is no longer an issue, It must have been slight over fill the one time by mistake, I do however have some oil residue on the driver side tail pipe, no oil smoke but oil wetness on the end of the tail pipe, does any one know what is happening with this engine of mine? it has 55000 miles on the rebuild, it has duel exhaust also.
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