Pcv sucking oil.

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Mar 6, 2014
Chico Ca.
1965 fj40 with I believe a 1.5f head. Webber conversation. Plugs foul with oil. Found oil is being sucked into PVC and then into intake. Has alot of vacuum happening. PVC valve is a newer one I found online. It had this terrible fitting attached to intake, one that comes in the conversation kit seems to be pipe thread and only for fuel nipple. Is there a smaller fitting that would draw less vacuum. We are stumped here. Oil really gets drawn up filler neck. It's strange help with idea please. I have a plug in the intake for now.





I don’t know ‘65... are you saying ‘65 had a positive crankcase valve? Where’s the PCV mounted? Is it mounted backwards? What does The pcv look like?

Here’s a pic of a restored ‘65, from HERE.

The filler is different from your’s.

Both my '65s have a pcv. I think the vacuum is just too strong perhaps due to Webber conversation. If PVC valve was backwards, I would think it would be held closed and not have any vacuum


The PVC is the thing connected to the orange hose in the above photos. That one was specific to late 67 through 69. It threads into the branch from the oil fill tube and ports into a tubing stub just under the carburetor. If you have a webber, the tubing stub was probably deleted and the kit just dumped it into the intake manifold. The bed news....that PVC is no longer available. However, you can substitute a PVC from a 2F and just use a barbed nipple at the oil fill tube.

Im amazed you didn't loose vacuum...thats generally what happens when the PVC fails.....if its sucking oil, I'd be checking compression...probable got some ring blow by.
[QUOTE="Mark Jennings, post: 1331855
The pcv was bad and I found this one that fits. Probably from a 2f. I have too much suction. How do others run the PVC Hove with the Webber conversation? Seems like the right spot but just crazy suction. About to put a second PVC valve inline perhaps to slow it down? Idk


The PCV is slightly open at idle and fully open at low manifold vacuum, e.g. wide open throttle. If its open to far at idle it won’t idle correctly. A 2F PCV should work. If you pinch off the hose, you should hear a change in idle if it’s working correctly.

PVC is working. My issue is oil being sucked into intake through the PVC at high rpm "driving". Oil makes it way all the way up filler tube.
Is the air inlet on the valve cover open? For the PCV to work correctly, there is a vent the the valve cover ported to the air filter so air can flow through the engine and out the PCV to the intake.
Is the air inlet on the valve cover open? For the PCV to work correctly, there is a vent the the valve cover ported to the air filter so air can flow through the engine and out the PCV to the intake.
If it wasn't I want have too much vacuum correct ??
The 2F has a baffle on the inside of the push rod cover.
I can see the baffle at the bottom of the filler tube. Seems to almost allow more oil through with this vacuum since it allows a sealed tube once oil is flinging around and then gets sucked up.
When it was stock, the pcv on my 74 connected to a metal tube molded into the insulator. The tube was about ½” for the hose but the tube was flattened where it entered the insulator and the hole inside the insulator was just a slit. Could you plug that fitting on yours with epoxy or braze it shut then drill it smaller?

Could it be you just have excessive blow by? You could always run a catch can. I'm real happy with mine.

Catch Can.jpg
No, no, no....sorry, I mean did you accidentally plug the valve cover vent when you installed the aftermarket air cleaner. The original should have had a hose from the air cleaner to the valve cover....that’s the air intake for the PCV system....air flushes the oil fumes out through the PCV to the manifold....the fitting you installed under the carburetor.

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