How to drain fuel quickly and safely from a pa32-R

Salty

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Salty
I like to do ferry flights on the weekends to the cheapest fuel in the area fill up. I have a fuel farm to hold surplus.

I can drain the outer tanks pretty easily and quickly with a siphon hose, but that still leaves 50 gallons on board that can't be quickly drained. Any clever tricks I haven't thought of for this? I've tried using the fuel drain lever, but that extremely slow. Pulling the drains from the tanks seems messy and unsafe.
 
I like to do ferry flights on the weekends to the cheapest fuel in the area fill up. I have a fuel farm to hold surplus.

I can drain the outer tanks pretty easily and quickly with a siphon hose, but that still leaves 50 gallons on board that can't be quickly drained. Any clever tricks I haven't thought of for this? I've tried using the fuel drain lever, but that extremely slow. Pulling the drains from the tanks seems messy and unsafe.
I had a tank at the flight school rigged up for stuff like this. It was an old Tidy Tank like this:

upload_2022-7-11_16-43-26.jpeg

I had a crank-type fuel pump on it, and a water-stop fuel filter, and a check valve in some plumbing around the filter. Stick the nozzle in the tank filler, with a short piece of 1" ID poly hose if necessary, and crank the pump backward. That sucks fuel out of the aircraft tank and around the filter via the bypass check valve. To put the fuel back in the airplane crank the pump the right way and the fuel goes through the filter; the check valve is closed in that direction.

Need a ground cable and clamp, too.

Later on I added another bypass: a ball valve that bypassed the pump and filter altogether. It was to make defuelling the high-wing airplanes easier. Do the backward-pump thing until the fuel is flowing, then open the bypass valve and let gravity do the work. No pumping.
 
I can't vouch for the Piper but when recalibrating the new fuel senders in the Navion, I pulled the quick drain out. It's not all that messy. I then jammed a piece of plastic tubing over where the quick drain came out and stuck the other end into a succession of VP Fuels race car jugs. As long as you don't have fuel falling through the air, static charge buildup isn't too much of an issue. Do this outside however.
 
I had a tank at the flight school rigged up for stuff like this. It was an old Tidy Tank like this:

View attachment 108573

I had a crank-type fuel pump on it, and a water-stop fuel filter, and a check valve in some plumbing around the filter. Stick the nozzle in the tank filler, with a short piece of 1" ID poly hose if necessary, and crank the pump backward. That sucks fuel out of the aircraft tank and around the filter via the bypass check valve. To put the fuel back in the airplane crank the pump the right way and the fuel goes through the filter; the check valve is closed in that direction.

Need a ground cable and clamp, too.

Later on I added another bypass: a ball valve that bypassed the pump and filter altogether. It was to make defuelling the high-wing airplanes easier. Do the backward-pump thing until the fuel is flowing, then open the bypass valve and let gravity do the work. No pumping.
You can't get a hose into the inner tank.
 
Be careful Salty, not a great idea in my book for many reasons, liability being one of the higher ones.
 
Be careful Salty, not a great idea in my book for many reasons, liability being one of the higher ones.
It's done all the time by mechanics, but shops have liability insurance. Even then it's done outdoors. Most airplanes don't have a shutoff at the tank outlet, so the tanks have to be drained if the plumbing, including the selector or shutoff valves, needs work. Sometimes the tanks themselves have to come out for repairs. Sometimes the quick-drain valve is leaking and has to be replaced; you get good at switching them real quick, and getting fuel all down your arm in the process. Stings in the armpit. I don't miss that at all.
 
Be careful Salty, not a great idea in my book for many reasons, liability being one of the higher ones.
I'm with you. Looking for a safe solution if it's out there already. I can live with leaving 50 gal in there if I have to.
 
It's done all the time by mechanics, but shops have liability insurance. Even then it's done outdoors. Most airplanes don't have a shutoff at the tank outlet, so the tanks have to be drained if the plumbing, including the selector or shutoff valves, needs work. Sometimes the tanks themselves have to come out for repairs. Sometimes the quick-drain valve is leaking and has to be replaced; you get good at switching them real quick, and getting fuel all down your arm in the process. Stings in the armpit. I don't miss that at all.
Doing it once for maintenance is a whole different thing. Doing it regularly it needs to be safe and clean.
 
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I am in the fuel business. Respectfully asking what is a fuel farm?
First off I would only use a tank, fuel hose with a ground wire built into it and the proper nozzle.
I have a few storage tanks and did squirrel away some fuel when I realized it was going up.
I have had a 100 gallon tank in the back of my pickup for many years, it is in my 3rd truck now that is what I use to move it around.
I would not risk hauling it and emptying it out of your plane, just too much to go wrong, IMO super risky using battery powered pump if you are using alligator clips for the power connection.
Definitely always handle gas outside.
I have filled up my pickup with cheaper gas when I was out of town and hauled to my airport to be put in my plane as needed.
But lately I just bought a bunch from my home airport before it went up and put it in a holding tank away from the airport. Pumped it from my truck to the tank and then will refill my tank in my truck and then into my plane outside on the ramp as needed. Is it worth it? IDK maybe if you already have the equipment like I do.

My buddy and I talked about filling a 3000 gallon tank I have. I Had trouble finding a supplier since I was not a airport.
My late buddy owned a dragstrip and had a 10000 gallon under ground tank for 100LL.He bought semi truck loads of it. He made it work by selling some of it to the racers and the rest he put in his planes.

I used a shaker hose to siphon out gas of one of my wing fuel tanks when I removed it. Too slow to use to ferry fuel and not grounded.
 
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I am in the fuel business. Respectfully asking what is a fuel farm?
In my case, it's a 90 gal aluminum tank on a trailer with a gas rated electric pump and a bonding wire.

Pumping it out of the plane is not an option. It would have to be drained in some way, and I'm not seeing a safe way to do it. I thought maybe somebody else had one. I know people talk all the time about removing fuel to carry more cargo etc....
 
Sometimes the quick-drain valve is leaking and has to be replaced; you get good at switching them real quick, and getting fuel all down your arm in the process. Stings in the armpit. I don't miss that at all.
I replaced a drain a drain valve like that in a 172. Very possible but maybe not the smartest thing to do on a plane.

I also have replaced drain valves on 275 gallon heating oil tanks with out emptying it. Heating oil is way safer than gasoline. 2 ways to do it. Plug the fill and vent pipes and pull the old valve out and hope you get the new one threaded in quickly.
Even better than that is to use a shop vac on one of the pipes and plug off the other. Turn the shopvac on outside and you can take your time swapping valves,works great. Remember heating oil and diesel is not gasoline. Never use a shopvac around gasoline!
 
I replaced a drain a drain valve like that in a 172. Very possible but maybe not the smartest thing to do on a plane.
You can fly the plane until the tanks are down to 1/4 full or so. Set the selector to left or right, or off if it's a Cessna. Jack the left gear leg up so that the right wing is lower, and the nose will also be a little lower. That shifts the fuel forward and outward in the right tank, away from the drain valve, so you can replace the drain valve easily. No spillage.
 
You can fly the plane until the tanks are down to 1/4 full or so. Set the selector to left or right, or off if it's a Cessna. Jack the left gear leg up so that the right wing is lower, and the nose will also be a little lower. That shifts the fuel forward and outward in the right tank, away from the drain valve, so you can replace the drain valve easily. No spillage.
Thanks for the tech tip Dan.
 
So, it sounds like I'm not ignorant of a simple solution that exists. Not really a safe way to do it.
 
Back when Cessnas came with wing PLUGS (not drains ) I learned the technique of tying a rag around your wrist to avoid getting 80/87 in the armpit.

When possible; my choice is to disconnect the fuel line at the Carb and place in the drain tank. The shutoff valve helps and the fuel rate is good.
 
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