First Engine Start - Aux Fuel Pump

[flybill7]

I'm hoping to start my Mattituck TMX-360 this weekend for the first time. I'm wondering about the stock aux fuel pump I have. Is it OK to start the pump "dry"? Is there a way to "prime the pump" so it sucks fuel out of the tanks for the first time?

[frankh]

or remove the fitting off the discharge side of the pump (at the inlet to the mechanical pump for example).

Put some fuel in the tank and start the pump.

Those little facets are pretty tough and will withstand dry running...don't do it for say half an hour obviously.


Frank

[JonJay]

Originally Posted by frankh

or remove the fitting off the discharge side of the pump (at the inlet to the mechanical pump for example).

Put some fuel in the tank and start the pump.

Those little facets are pretty tough and will withstand dry running...don't do it for say half an hour obviously.


Frank

You need to do this anyway to verify that your system can supply full fuel flow. Run it into a measured jar or jug, time it, and do the math. I believe for that engine you will need to insure at least 18gph, minimum. It is easiest to remove your fuel hose from your carb or servo and that is where you need to measure for full flow anyway.
Your pump wont be dry for more than a second or two.

[flion]

You should also run with a filter for a while to be sure any debris in the system are flushed. Actually, on mine, I ran an external transfer pump with a filter through the selector valve and then hooked up my (high pressure for FI) aux pump and ran it for a few seconds to the firewall and a collecting hose there before finally hooking it up to the engine and pressurizing the whole system with the aux pump.

[Guy Prevost]

You can also blow in your fuel vent tubes to help prime the pump.

[rocketbob]

The facet pumps have a dry lift spec and its somewhere around 2ft. So its not a problem to start it dry which will only be at most five seconds.

[flybill7]

Thanks, great info!