Mailing List flyrotary@lancaironline.net Message #28577
From: Al Gietzen <ALVentures@cox.net>
Subject: RE: [FlyRotary] Re: Fuel filter selection
Date: Mon, 19 Dec 2005 09:05:09 -0800
To: 'Rotary motors in aircraft' <flyrotary@lancaironline.net>

Ernest wrote:

>

Summit has another filter that looks nearly identical that goes down to

35 microns, with a stainless steel mesh screen. It isn't rated for as

much flow, but it still borders on the ridiculously high for our

application. I'm going to install one of those after the pumps, and one

of the PRM-81794 before. The PRM will insure the fuels clean and dry,

and the other will catch any pieces that come loose from the pump. I

feel very comfortable with that design.

 

I may also install one of the glass filter that go inline with the hose,

putting it forward of the firewall. They're only $10 and it would give

me a decent preflight check that nothing has gone horribly wrong

upstream while I wasn't looking. Is that sound reasoning?

-------------------

 

My philosophy is that you put a water/debris trap, or sump, upstream from the pump; but nothing much finer than a screen door screen.  The last thing you want is pressure drop upstream from the pump, and a fine filter with a bit of dirt in it could definitely cause a vapor lock.  The PRM-81794 claims filtering down to 2 microns, and pressure capability of 90 psi.  That says “downstream from the pump” to me.

 

Al

Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster