Fuel boost pump update

January 1989

CP 57's fuel pump alert caused many letters and phone calls and there still appears to be much confusion. RAF recommends, as a first choice, a Facet boost pump with 370 x 3/8 flare fittings and with a nylon foot valve on the inlet side and a nylon plunger valve on the outlet side. The Facet part numbers for this pump are:

40108 - 12v 6 psi max. 4.5 psi min. 37 degree flare
40154 - 24v 6 psi max. 4.5 psi min. 37 degree flare

If you do not want to install the aircraft style 37 degree x 3/8 flared fitting type pump, due to plumbing requirements or space or whatever, the next best choice would be to use a pump with 1/8 - 27 national pipe thread internal or female threads, requiring elbows such as AN822-6 to go to 37 degreee x 3/8 flared fittings. 40106 - 12v 6 psi/4.5 psi, 1/8-27 NPT internal threads. 40082 or 40164 - 24v 6 psi/4.5 psi, 1/8 -27 internal threads. Facet does not manufacture a 3/8 - 18 internally threaded pump that meets the 6/4.5 psi fuel pressure requirement with nylon valves.

For this reason, RAF is not recommending the larger internal thread style pumps. Anyone who is using one of thesc pumps should be very aware of the fact that while the outlet plunger valve may be nylon, the intake valve is Buna or rubber and is a check valve, not a foot valve. A check valvc will maintain full fuel pressure on your fuel, system down stream of the fuel pump and against your needle and seat float valve in the carb. This is not necessary nor is it desirable in any RAF design. If you are using one of these pumps, a careful inspection of the intake valve at least once a year is strongly recommended.

Ian Wilde from Olney, England, a Long-EZ builder/flyer, sent this information in and we have included it here to help those builder/flyers of RAF designs in England. "Facet fuel pump, #40108 is not easily obtainable here in England, however, I am told by the Facet agents that #40105 is the replacement for 480615 and that this pump has all nylon parts. (40105 has a maximum fuel pressure of 4.5 psi which should be OK all the pumps RAF is now recommending have a 6 psi maximum). Price in the UK is 30.00 Sterling. Better still, the plunger assembly of #480615 can be replaced with an all nylon assembly as per #40105 at a cost, including labor, of 10.93 Sterling, including tax and postage. I have had mine modified and I am very happy with it. Anyone interested should contact the Facet agent:

FSE (Fuel System Enterprises)
180 Hersham Road
Hersham
Walton-on-Thames
Surrey, KT12 5QE
Phone: 0932 231973
Telex: 925109 Fuelit

My contact was Mr. Peter Huxley"

Copyright 1999-2017 ez.org All Rights Reserved