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Tips re: draining tank w/o a pump?

dbhill916

Well Known Member
Hi All,

I'm looking for tips / suggestions on how to drain my tank without benefit of an operational fuel pump.

I've got about 3 gallons in it which I want to use to find leaks before I cluttered things up any further with wiring and control rigging. When 12V is applied to the pump, I can hear it making the (presumed) appropriate noises, but there is essentially no flow through the supply side. There's gas in the bowl of the gascolator, but the outlet of the gascolator has a mere dribble that appears to be simply the static pressure from the fuel in the tank. (Yes, I opened the cutoff valve.)

I'm left with the conclusion that the pump is bad. I'm looking for some way to avoid having ~3 gal of gas to clean up when I get the replacement.

Suggestions on removal?

Alternate interpretation of my observations?

Thanks in advance,
-dbh
 
Possible plugging inside the tank at the outlet, possible plugging in the line somewhere, possible plugging of the gascolator screen. Some have found a gummy residue in the gascolator. I would start there because it is easiest. You could rig something to hold the gascolator drain open and put a 5 gallon bucket below it. Eventually you will have to do a fuel system flow test though.

Haven't heard of a DOA fuel pump in the kit. Is it possible that the fuel shutoff valve is not turning even though the handle is moving?

When building I blew out the lines thoroughly before installing them.
 
It takes a minute or so to prime the pump first time. You might check your fuel valve to see if it inadvertently got shut.
 
It takes a minute or so to prime the pump first time. You might check your fuel valve to see if it inadvertently got shut.

To help with priming the first time, attach some vinyl tubing to the tank vent and blow (by mouth, it doesn't take much pressure) to help start the flow.
 
To Drain Fuel Tank

David,

I?m not sure this method would be approved by whoever is in charge, but this is what I did.

I picked up a ?? steel rod from the hardware store, a funnel and gas can. I cut the rod to a length just longer that the distance from the fuel drain valve to the ground. I placed the funnel in the gas can, and the rod in the funnel. I wedged the rod under the drain to hold it open and the fuel ran down the rod, through the funnel, into the gas can. It probable took 15 minutes to drain 5 gallons but it was reasonable clean.

Also, you might cut a ?V? in the top of the steel rod to help wedge it under the drain and to help fuel pass by.

In case you end up draining the tank...I hope this helps.
 
Although I had my share in fuel flow problems in between gascolator and tank I cannot provide more help for your problem than to check the lines and maybe try a different pump. I just wanted to remind you to be careful when draining the system into canister or into a bucket. Even at a low flow rate the flow might build up static electricity which could discharge close to the gas container. Make sure that you ground the airframe and the canister/bucket during the draining process and have an extinguisher ready just in case. Gosh, I hate splashing around with fuel, can you tell?
 
fuel pump

Check fuel pump has the fuel connections the right way around
and if there is only a few gallons of fuel if you lower the tail down to the gnd you may be able to remove the outlet from the fuel tank without fuel leaking and after placing a bucket under the outlet slowly raise the tail
 
Drain gas tank

David,

I?m not sure this method would be approved by whoever is in charge, but this is what I did.

I picked up a ?? steel rod from the hardware store, a funnel and gas can. I cut the rod to a length just longer that the distance from the fuel drain valve to the ground. I placed the funnel in the gas can, and the rod in the funnel. I wedged the rod under the drain to hold it open and the fuel ran down the rod, through the funnel, into the gas can. It probable took 15 minutes to drain 5 gallons but it was reasonable clean.

Also, you might cut a ?V? in the top of the steel rod to help wedge it under the drain and to help fuel pass by.

In case you end up draining the tank...I hope this helps.


Dean,
Excellent suggestion! Drained my tank easy. Your idea works!

Thankyou
Tim
 
update

Gents,

thanks to all for your suggestions. It turned out to be a bad power supply. (I've never worked with a fuel pump before so I didn't know that it wasn't making the right kind of noise with my bad power supply.) Now that I've been able to pressure test my plumbing, I have one leak to address but I'll start a new thread for that question.

Tumper?thanks for the excellent trick to get the final pints of fuel out of the system, it worked like a charm!

-dbh
 
Assuming the pump is wired correctly, check to see if the pump wasn't physically installed backward. I discovered this problem on a friend's Kitfox.
 
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