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Hi, just curious if two breathers are necessary. Passenger side has a PCV valve and breather, driver side has breather. I was going to put in a push in oil fill cap on the passenger side instead.
From: At my Bar drinking and wrenching in Lafayette Colorado
It only need one breather. Normally, due to crankshaft rotation and airflow through the crankcase, the PCV is installed on the driver's side with the breather on the passenger side. But either way will work, as long as the PCV and breather are installed in opposite valve covers to create ventilation through the engine.
Lars
At first I thought I saw a spec of dust on the engine. Then realized it was on my lap-top monitor.
Love those breathers. That's a class act right there.
What you could do because the twin breathers match so nice is, block off the passenger unit. It would just be for looks only. Fake.
Maybe some type of plastic plug inserted into the breather tube. Or even caulk the breather closed. The PCV will still work fine, even better.
I think Moroso has the rubber grommets that fit into the valve cover ports, 1 1/4". However, with theirs, I believe they came closed off and you had to slit open the grommet bottom for what ever air flow you needed. You want zero flow.
Not a big fan of those oil fill plugs. Most are just a boring rubber stopper that usually leak vapors.
Lots of people get the PCV system wrong. I have seen two PCV valves, no inlet. Think, cross ventilation. Fresh air goes in one side. Gets sucked out the other side.
Last edited by HeadsU.P.; Oct 21, 2021 at 03:44 PM.
Nice engine! The power brake filter (carbon canister for fuel vapor) needs to be mounted vertical for proper function. Fuel vapor condenses in the filter and drips back down toward the manifold.
Usually the pcv is venting blow by that gets past the rings. The breather doesn’t do much breathing with older engines. Used to see early 60’s cars with road draft vent tubes blowing more out the vent tube than out the exhaust.
You are misunderstanding the concept of the cross ventilation system in this case.
If two breathers, one each valve cover, no PCV, racing style, then each breather allows crankcase vapors to escape on its own. (exhausting)
But in cross ventilation with a PCV Valve in place, vapors are withdrawn by vacuum as you know. That causes a negative pressure in the crankcase. But air can not leave the crankcase efficiently unless air is allowed back in. That is the sole purpose of the breather on the other V.C.. Consider it an air intake.
There is often some type of filter medium inside the better breathers. To clean the fresh air intake port before entering the crankcase.
Last edited by HeadsU.P.; Oct 24, 2021 at 08:46 AM.
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PCV question
