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I don't know if you realize, with no PCV system the exhaust blowby gases are likely to end up in the passenger compartment. I very briefly had my PCV removed and it got smelly in a hurry.
edit: Um, that isn't the PCV hose I was thinking of. There should be a 3/8" hose coming off the PCV valve to the base of the carb. That looks like a vacuum line for the thermal valve on the air cleaner.
As Kenneth stated just cap the port at the carb. I'll add that the other issue you may run into is if you have blowby, the engine will push engine oil out the fill tube or dipstick. I would also look for a 14" air filter that fits the air cleaner housing.
Location: Big Lake,MN..Spent most of my life in Boston
Posts: 714
OK on the filter size...I'll make that change when this one gets dirty. I did put a breather cap in place of the PCV....And you are all correct....didn't take long for fumes to get in car,
Would a filtered valve cover breather work..(They look like mini air cleaner)
Your new air cleaner may have a punch out hole in the bottom pan. Should have come with a plastic adapter for that purpose to connect to the PCV hose. My PCV connects to a large 3/8 port at the bottom of the carb. I would use the PCV if possible.
Well the first post just disappeared, so i made this one, then the first one came back. I tried to delete it but now it wont go away... lol, oh well.
Last edited by steverw; May 17th, 2016 at 06:51 PM.
Reason: MORE
Actually the punch out in air cleaner base is connected to a breather that would be on the opposite side of the engine from the PCV to aid if the PCV cannot take care of the blowby. It is no way used for a PCV.
I run a pcv valve in the driver side valve cover connected to the big port on the carb, and a breather on the passenger side valve cover. My current MT valve covers only had one side drilled. They are the old style with the rocket logo. I didn't want to drill the other one, so I put the breather on the oil filler neck.
There is absolutely NO reason to remove the PCV valve. The PCV doesn't hurt performance in any way and it helps with fumes. Deleting it frankly shows a lack of understanding in how engines work. If you did this for looks, stop it. Also, there are LOTS of ways to run a PCV valve that don't require it to plug into the valve covers. See the 1970 W-30 intake, as an example.
Location: Big Lake,MN..Spent most of my life in Boston
Posts: 714
Few items...very limited smoke if any coming from valve cover. When I run it hard and for long distance I get some.
My goal was to and is replacing the original air cleaner holder as you see in photos.
The base of the air cleaner holder does have a cut out for a 1/2 line. I will be installing a rigid hose and installing a PCV back into the valve cover where the original one was located.
In previous posts I had inquired about changing the air cleaner assembly and had asked for suggestions on PCV and what to install in place of old PCV and I was sent photos of what I now have (The chrome breather).
And if you going to give out advise Joe I would appreciate if you eliminate your degrading comments about my knowledge of engines....that attitude doesn't fly
Location: Big Lake,MN..Spent most of my life in Boston
Posts: 714
Also i have two fuel filters...one at pump and the one noted at base of carb....i have insulated it due to its location. That area as you know gets hot. I have had that set up for three years and has eliminated contamination issues. I'm comfortable with it.
If you are referring to this prior thread, we provided info on how to configure the fresh air breather, not the PCV valve. I think the confusion comes from the unusual configuration of the early 1960s Oldsmobile PCV valve, which does not work like a modern one. I assume your original valve looked like this:
Unfortunately, these really don't work that well, which is why they were replaced after 1964 with the more conventional PCV system. If you want to retain this original valve, use the fitting that bolts to the underside of the aftermarket air cleaner, as shown in the older thread.
If all you care about is functionality, I suggest something like what I did on my 1962. Get one of the breather caps that has a hole for a PCV valve:
Install this in one of the valve covers and connect the PCV valve barb to manifold vacuum below the carb (or the large port on the base of the carb - you can tee it into the brake booster line). Use either an open breather on the other valve cover (or oil fill tube) or use a closed breather with a hose to the port in the air cleaner. The latter is a little better for collecting and controlling any fumes.
May 17th, 2016, 02:35 PM
