O-360 Dies w/ Facet pump on Low power

Redbud40 · #1 01-26-2022, 10:30 PM

Soooo O- 360 , MA 4-5 carb ,dual p mags. Some time ago I was taxiing out and turned Facet electric pump on and realized the engine started to stumble and turned pump off. I only use pump when I notice low fuel press.
During a touch and go I had turned pump on for 0.5 press. I forgot to turn off once press came up and on the roll out waiting to stabilize the engine died. Rut Roh.

I remembered the situation of low power from before and turned pump off used a flooded engine start procedure ( mixture cutoff) and engine fired back up.

Next day I did some testing. Cold engine pump on 4.0 psi. Start procedure, engine won’t start. Turn pump off. Start procedure, engine starts. While engine running at idle , turn pump on, engine dies.... Flooded engine start procedure, engine starts. Run to 1000 RPM , pump on engine runs.

So, engine seems to flood at low power setting or no power ( starting) with the Facet pump on.

Engine/ Carb experts. What say you. Thanks
Red

PCHunt · #2 01-26-2022, 10:36 PM

I'm no expert, but the first thing I would check is the float and float valve in the carburetor. From your description, it sounds like the 4.0 psi is forcing too much fuel through the carb. The float valve should prevent that.

YMMV, as always.

Walt · #3 01-27-2022, 06:44 AM

Quote:

Originally Posted by PCHunt

I'm no expert, but the first thing I would check is the float and float valve in the carburetor. From your description, it sounds like the 4.0 psi is forcing too much fuel through the carb. The float valve should prevent that.

YMMV, as always.

Agree, time to get the carb overhauled. I recommend carb OH at least every 10 yrs.

Redbud40 · #4 02-10-2022, 08:12 PM

Took carb to experts in Justin. Float and needle seat replaced and cleaned up. Put back on plane and still have the symptoms. Maybe I’m thinking a problem where there isn’t one? Operational you don’t use Facet boost pump except at higher power settings. However if you forget and leave it on ( like I did on roll out) the engine I don’t think should die because of too much fuel.
5.0 fuel pressure output on gauge with pump on, engine not running.
Experts ?.

One solution I heard. Just don’t turn on at low power settings.

Planecrazy232 · #5 02-10-2022, 09:28 PM

Do you have a primer system on your engine?

WingsOnWheels · #6 02-11-2022, 05:59 AM

Quote:

Originally Posted by Planecrazy232

Do you have a primer system on your engine?

I was going to ask the same thing before I scrolled down.

Redbud40 · #7 02-11-2022, 06:17 AM

No primer.

Southern Pete · #8 02-11-2022, 06:23 AM

Sounds like there is a problem with the carb, should be able to run the Facet continually without any impact on how the engine runs.

Redbud40 · #9 02-11-2022, 07:10 AM

Anyone know of a Facet pump going bad on the high side? ie for some reason it starts putting out way more than 5 psi?

lr172 · #10 02-11-2022, 07:15 AM

Quote:

Originally Posted by Redbud40

Anyone know of a Facet pump going bad on the high side? ie for some reason it starts putting out way more than 5 psi?

Yes, pumps can fail high and often do. My first step in addressing this is replacing that pump. Pump on=bad, pump off=good means replace the pump! In normal situations, it should be putting out about the same pressure as the mechanical pump. Assuming the mech pump is working well, a carb should not be an issue.

FYI, overfilling the bowl is just as often a failing float as it is a bad needle/seat. Hopefully your guy checkef for that while in there.

Larry