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right, lost another oil cap today on the highway (and to the car behind me mit flashing lights "something fell off the truck beside me") on the 'new' engine and i think it is due to some sort of crankcase pressure building up and not blow by as i suspected with the last noisy donk.

some years back i thought i was doin' the right thing by creating a cross flow copying an idea i saw somewhere. It was a paper air filter element from a lawn mower attached to the rhs rocker cover - the idea being to filter any air going through block to the other side lhs rocker cover where the other outlet simply went straight to the PCV valve in the manifold

given that the old manifold is in use on the 'new' motor along with a new air filter for rocker cover. I am wondering if this filter is restricting air flow causing the crankcase pressure. Afterall it was designed to filter air being sucked in by a piston , not to flow naturally.

Or maybe this is typical of an EA81 with nearly 400,000km on it . still runs sweet as

have many modifed their pcv stuff in the past??

for those few of you that have read this, I have found the answer in theory from the Subie manuals for my GLTA.

air needs to enter crankcase from the dizzy side rocker cover which normally comes from the outside of the air filter on the casing. I have used the mower air filter mounted just above rocker cover.

the alternator side rocker breather connects to the PCV valve directly on mine. the gregorys shows a diagram of a line connecting to inside the air filter to this side.

The subie manual explains that at light throttle the manifold vacuum pulls air through the crankcase , but at full throttle or when there is little or no manifold vacuum the crankcase air is then drawn through the inside of the air filter by the airflow there above the throttle plate. This is the bit i deleted from my conversion a long time ago to avoid chance of air filter getting oiled up

NOW I know what to try...

Yahoo !!