Leaky oil breather cap

[1960_tbirdman]

This past weekend, after 20 miles of highway driving, there seems to be oil coming from the breather cap. This never happened before. I recently did the PCV valve conversion using a spacer plate under the carburetor but did not change the original oil breather cap. I had driven it on the streets with no issues until this weekend. I saw some past postings about this but did not understand the messages posted as to what the problem may be. Thanks for any assistance.

[simplyconnected]

How bad is your blowby? PCV is great IF it sucks out more fumes than are being created by the piston blowby.

How many breathers do you have?

What route does your blowby take?

[1960_tbirdman]

Before the PCV valve conversion, you could see the smoke coming from hood at stop. It also came in through center vent during driving but we discovered hole in A/C housing while doing the conversion.

I have one breather cap, looks original. I now have oil that seems to be coming from cap and runs along valve cover,

[Joe Johnston]

Any chance of the new PCV installed backwards? They act like a check valve and only flow one way - easy to do if its the type installed in a hose, but most can't be done backwards as one end fits in a grommet.

Spacer plate under the carb? Could you have connected the hose to the fitting for a water passage? (I'm only familiar with Bullet Birds and they have a water passage in their spacer. Perhaps 58-60's don't?)

Posting a couple of pictures will help.

[DKheld]

x2 with Joe

When I was installing mine I found that there are a coupe of different types of spacers. The first one I bought drew air from the secondaries when installed on my carb so the only time it worked was when you opened it up. Also the spacers can be installed upside down - don't ask how I know -

If you have a vacuum gauge see if you have any vacuum at the inlet. I'm guessing no and since you don't have a road draft tube any longer it's pushing all the fumes out the breather.

Eric

[Tbird1044]

It's easy to check the PCV valve setup by checking if you pull a good vacuum through the valve when the engine is running. The original oil breather cap should be replaced with a cap that has a hose fitting on it, so you can run that hose off of the cap to a small filter installed in the air cleaner. This serves two purposes. If you have excess vapors they will be directed back to the air cleaner. If your PCV valve is pulling more vacuum than you have blowby, then it will pull filtered air back into your engine crankcase.
Nyles

[1960_tbirdman]

I know we installed the spacer correctly as we double checked that.

I will check the vacuum and see. I am getting oil out the breather cap as well.

Thanks for replies.