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View Full Version : Removing the draft tube and converting to a PCV valve



1965JNC
04-13-2021, 10:23 PM
Has anyone done this to their car? I have a 59 with a 352. I recently installed a new Edelbrock AVS carb. This carb had a vacuum port in the back that could be used for a PCV valve so I removed the draft tube, made an adapter that fit in the hole the draft tube was in then installed a PCV grommet and a PCV valve with a 90 degree fitting. Six inches of hose and it was connected to the vacuum port. I no longer smell engine fumes when I'm at a light.
But I now notice that a little bit of engine oil is being pushed out of the oil breather. After a ride there a light film of oil on the passenger side of my fire wall. Have no idea why this is happening. it did not happen with the draft tube. The PCV valve I bought said it would work on a later Ford with a 352 engine so I assume its sized correctly.

Finster
04-14-2021, 02:50 PM
Hi,
I did a similar switch 10 years ago because I was tired of smelling exhaust while at stop lights. The smell gets even worse when you have the air vents open. I also switched to a 600CFM Edelbrock carb with the extra port. I basically have a hose connected to a grommet that has a PCV valve from a large engine.

I know when looking into this years ago some people experienced a misting effect out of the breather tube and then when they removed the PCV valve the misting disappeared but I dont think that is the solution as it could cause other issues. I cant remember if it was due to the size of the valve etc.

The only issue I have is that the Carb has gotten much dirtier than would normally be the case over the years.

The oil issue is strange . Maybe double check that the exhaust pipe flange gaskets are good. I noticed one of mine had a leak after I made the change and I didnt notice it before the change. Check that the PCV valve is in the right way. Also - check its a one for a larger engine. Otherwise I cant help. You should definitely not be experiencing this problem.
Good luck

1965JNC
04-14-2021, 10:02 PM
Thanks,
I think I'll try a new PCV for a larger engine. I searched this problem on line and it seems to be quite common.