MA4SPA Carburetor Overflow

Getting ready for first engine start and ran into a glitch. I put 5 gallons in each tank, then drained each tank to clean them out. Re-fueled then disconnected the fuel line from the carb and ran the boost pump, switched tanks, and ran the pump again to make sure the lines were cleaned out. Fuel flow on the boost pump showed 6.6 gal/hour. I connected the fuel line to the carb and turned on the boost pump to see if there were any fuel fitting leaks with the system pressurized. The system showed 5.6 psi but the pump wouldn't shut off although pressure dropped to 3.2 psi. Turned the pump off and had gas leaking out of the drain in the filter box

The carb was overhauled in Sep 2009. Before I start tearing into a carb, any suggestions?

Thanks,
Dave
RV-6 - getting real close

This is a common problem for carbs that have sat for some time. Tap it on the side with a rubber mallet to unstick the float. That should solve the problem.

Fuel flow too low?

Are those fuel flow numbers ok? I thought the boost pump should be able to supply the engine at full power, which would be more than 6 gph, right?

Fuel Flow

I think the fuel flow number is low too. The Facet ES40108 is rated 15 gph @ 3 psi.

Got the carb float valve unstuck by removing the carb, draining it, inverting and shaking it.

My fuel system is: boost pump - gascolator - engine driven pump - fuel flow sender - carburetor. With the boost pump on (3.1psi/0.0 gph) I opened the gascolator drain valve, and fuel rushes out like a water hose. Tomorrow I'll visually check flow at each fitting.

Dave