Centrisep Inlet Separator
If you are operating the Centrisep Inlet Particle Separator on your aircraft and having to do engine washes often, check the drain valve assembly P/N CB00553-1D2321. In the bottom of the baffle where the drain is look carefully at the drain valve. There should be a red rubber flapper valve in the valve assembly and you should see the nub in the center of the valve. This allows the water to drain and when the engine is started the vacuum created pulls the flapper up against the valve. If you are not sure, detach the drain line from the bottom and take out the valve assembly. If there is no flapper on the valve, there is nothing stopping that big vacuum ( engine ) from sucking dirt up that one inch straw. Especially if you operate in sandy or dirty environments this can shorten the life of your engine.
There is no part number given for the flapper.
When reattaching the line to the bottom of the drain pan, be sure to maintain clearance from the transmission sump case.
When you tighten the line it tends to force the line forward into the sump case.
The photo attached shows the valve without the flapper.
Helicopter Maintenance Manager
Sacramento Metro Fire