facet fuel pump failure //caution

cardiffrob · Post by **cardiffrob** » Fri Jun 26, 2009 10:40 am

If it helps, I've run a Facet 'box' pump on every Midget/Sprite I've built over the last 10+ years without a failure. These are the 40105 model with the bronzed appearance.

They seem to have an almost unrestricted flow when switched off so yours must have stuck with the valve at the far end of the stroke? Have you been able to diagnose the failure? In a FRED I've got a good 2 feet of drop so that I might be able to keep it going on gravity alone, so long as it doesn't stop.

Maybe 2 facet pumps fed from the tank. Only one running at a time (you can hear/feel them running) so that if one fails you can keep running due to gravity feed but in normal operation the running pump will flow fuel to the carb and also reverse-flow fuel through the other pump and back into the tank. Might even help to prevent the fuel overheating?

Does this make sense?

cardiffrob · Post by **cardiffrob** » Sat Jun 27, 2009 3:30 pm

hat happened to the other postson this topic? Im sure the were a few more before mine.

mcfadyeanda · Post by **mcfadyeanda** » Sat Jun 27, 2009 6:18 pm

LAA TADS 074A at:
http://www.lightaircraftassociation.co. ... ONG-EZ.pdf
describes some problems with the much older 'square' facet pumps.
Viz.
1.
Due to problems with fuel boost pump failing due to seals deteriorating in Avgas, replace Facet fuel pump types 480616, 489615, 40023 with type 40108 which has appropriate seal material for Avgas as discussed in CP 57, 58, 60. See also CP 47 re importance of correct fuel pump pressure.

The 'CP*' documents referred to are at:
http://www.cozybuilders.org/Canard_Pusher/

DMcf