Leak from oil fill cap.

66Hardtop

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I have no more valve cover leak but now I have oil coming from the breather/fill cap on my 66 383. I checked the pcv valve and it seems to be ok. Anyone have this happen before? Engine runs great and haven't had to add any oil .
 
Stock valve covers? Can you see a baffle in there with the breather removed? If the media inside the breather is saturated it will spit oil onto the cover. How did you test the pcv valve?
 
Yes they are stock covers with the baffle. I checked by taking it off and blowing/sucking on it.
 
Clean the cap with solvent and blow the gunk out of it, ( it's the original 66 breather cap, I assume). The PCV. Valve should rattle when you shake it too.
What weight oil are you using? Should be 10-30 or 10-40 not 5w-30.
 
My knowledge of Mopar engines is limited, I admit but is there oil deflectors on the rockers of some of the engines?
All I can think of other wise is extreme blow by.
A dirty PCV valve will cause this too since the expanding oil filled air has to go somewhere as menitoned by Matt.

Also check the vac hose that the PCV is connected to.
If it's collapsed or blocked a new PCV valve woun't help suck the fumes into the intake.
 
Try starting the engine with the PCV out of the grommet and the oil cap off. If you are getting lots of fumes out of the valve cover (blow by) that is the cause of your oil leakage. As engines wear, at some point the PCV system can no longer keep up with the excess vapors and a leak results.


Dave
 
I did a few things you guys mentioned I checked the plugs and they are a perfect tan color. With it running I pulled both pcv and breather cap off and no fumes but a very tiny bit of smoke from the pcv side. I did clean the breather and It was pretty gunked up. I'm using 10W-40 but will be switching to 15W-40 once the weather gets warmer. It has 89,000 miles on the odometer currently. It had new rings put in at 27,836 for some reason.
 
BEFORE you get all excited, those OEM breather caps have a "hogs hair" filter in them. It should be lightly oiled so it catches dust THERE rather than getting it pulled into the engine via the pcv vacuum. Wash the cap in solvent, as mentioned. Then let the normal things just happen to put oil back into the filter area. It IS possible that when it might be a bit too much, a small drop or so might end up on the valve cover if the car sits for a good while. Just normal, no more, no less.

IF you're concerned, get a later model Chrysler breather cap that has a hose nipple on it. It should be "sealed" and also have a foam filter in it. NO leaks or drips, but not OEM correct for your car. But it is for a '70+ Chrysler product and "works".

Or, the OEM cap for a '67 CAP-spec engine will work, too, and look more period correct.

DO keep the pcv valve cleaned with some spray carb cleaner, for good measure. It should rattle freely.

Again, what you're seeing is completely normal, from my experiences.

CBODY67
 
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