Mailing List flyrotary@lancaironline.net Message #16990
From: Tracy Crook <lors01@msn.com>
Subject: Re: [FlyRotary] Re: Vapor lock
Date: Fri, 11 Feb 2005 17:19:12 -0500
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Bottom posting this time..........
-----

> I'm not sure that I understand vapor lock completely.  Is the problem
> that the fuel gets hot, or that the fuel boils and then the pumps no
> longer work?
>
> I have a plan for a stone cold simple fuel system.  With only one tank
> positioned high, I plan to put both fuel pumps directly under the tank
> which is located behind the cabin (tractor configuration).  Position the
> fuel regulator beside the pump, and I will only having a single line
> running out to the engine compartment.  Think of it as one LONG header.
> The issue will be that the fuel will not 'circulate'.  What goes out to
> the header at the engine will stay there till it gets used.
>
> Is this a prescription for 'vapor lock', or will any boiling fuel simply
> get blown through the injectors?
>
Hi, Ernest....I might have it wrong, but I seem to recall that I was told to
put the fuel pressure regulator just AFTER the injectors/fuel rail. That's
what I did...maybe that's part of my problem? 
 Paul Conner

I'd say no, that (regulator position) was not the problem.  What I would want to know is how big is that header tank, where is it, what is it made of, how is it vented and does it have to pull fuel through the boost pump.  That's where I'd look first.
 
Tracy (very wary of sump tanks on EFI)
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster