When
I saw others that had added a PCV trap I was a little skeptical that it
would increase fuel efficiency, but after thinking it over I changed my
mind.
Over the years I had cleaned or replaced quite a few PCV
valves and the amount of deposits and crud they accumulate can be
considerable. What doesn't get deposited there, will end up on the
intake valves, piston crown and possibly the exhaust valves . For
certain, these gasses and vapors are not good for an engine.
I
had hoped to make a minor improvement by placing my filter jar between
the valve cover and the PCV valve rather than between the PCV valve and
the manifold. It turned out to be a simple project. The idea is the
keep the PCV valve clean.
The
original PCV valve was cleaned with acetone and glued with Gorilla
Glue. Silicone rubber would work as well. The 3/8" 90° elbow also was
glued in place. A similar 90° fitting was used at the valve cover to replace the PCV valve with a 3/8 hose connection.
Once
it was assembled, I tested it for leaks by covering one connection and
sucking on the hose. It was then attached to the inside fender with a
nylon cable tie and new hoses installed.
The first time the
engine was started, a splash of oil and whatever was visible on the
inside of the glass jar near the bottom, showing that it does indeed filter.
When
large accumulations of blow-by gases remain and condense in the engine,
dilution of the engine oil would occur to form water, soot, resins, and
acids, resulting in the formation of sludge and varnishes. This happens
more frequently on vehicles during numerous starting and stopping
conditions, excessive idling and when the engine is not allowed to warm
up.
When
I am satisfied with the filter, I may consider placing a second, larger jar in
line with it for my water/methane vapor injection. I figure by doing it
that way, the PCV valve will reduce the chance of water entering the
engine at idle, since the valve closes until engine load increases (or at least is supposed to).
There
are various claims as to whether this type of modification helps gas
mileage or not. I suspect that the packing in the jar is restrictive
enough on some cars to reduce the vacuum lost by the PCV valve. No
matter. I am happy that I am keeping some of the crud out of the
combustion chamber. Some systems do not have a PCV valve, just a restrictor. [source Chiltons]
