Subaru Crosstrek and XV Forums banner

Crawford AOS clean

1416 Views 12 Replies 5 Participants Last post by  Panelhead
Needed to pull the Crawford Baja AOS off for pending dealer visit. Found it heavier than when installed. Only 2500 miles with it on 2.5 liter Crosstrek.
Poured a 1/4 oz of thin Wood Button Circle Metal Fashion accessory
reddish looking oil from AOS. No water. Must be heavily baffled, had to rotate and twist to extract a little more several times. Flushed unit from top port with brake cleaner and then from lower port. Discolored brake cleaner is all that came out.
Engine has not used any measurable oil in 4100 miles since last oil change. Will be on 6000 OCI for next three. Plan on catching the oil to monitor color and viscosity. Plus volume.
See less See more
1 - 1 of 13 Posts
My understanding was that the Crawfor AOS is maintenance free. The unit separates the oil from the recirculated PVC air and then what it catches eventually returns to the engine via the lower hose back through the PCV valve. Unlike others that have a manual valve that requires dumping from time to time. So you get the oil removed to help keep the backsides of the valves clean yet don’t have to worry about dumping the can.

From their webpage:

Not a Catch Can - Closed Loop and Maintenance Free

An AOS uses centrifugal force to force your engine’s oil through an internal labyrinth system, which makes the oil separate from engine condensation. A catch-can simply collects oil and requires one to either manually empty or pour back in the same, dirty oil. An AOS will automatically drain clean, separated oil back into your engine, without any maintenance required whatsoever. Just install and forget.
1 - 1 of 13 Posts