Fuel transfer

[DonMuncy]

On the flight home yesterday, I intentionally ran my left fuel tank dry, with the intent to calibrate a fuel dip stick. My plan is to call the fuel truck and top off the right tank and transfer it to the left tank a gallon at a time while marking the levels on my stick. I anticipate using a syphon hose to fill my gallon jug. What is the consensus of MSers for avoiding static sparks, both for the "syphoning from", and the "adding to" the tanks.

[Igor_U]

I would not bother with 1 gallon increments. I did my Home Depot 5 gallon at the time and is sufficient accuracy..

First 7-8 gallons do not show (on my W with 32g tank) on a stick as the fuel level is bellow the filling port. I would fly to the airport with self serve and do it there, 5 gal at the time. you can interpolate 1 gal mark in between.

 

Now,

I recently installed new fuel gauges (Aerospace logic) that need calibration in 2 gal increments. Emptied all the fuel from tank (other I run dry) by pulling tyhe drain plugs while tanks were grounded, outside the hangar...

It takes time to do 64 gallons 2 gal at the time. Good luck.

 

 

[DonMuncy]

5 minutes ago, Igor_U said:

I would not bother with 1 gallon increments. I did my Home Depot 5 gallon at the time and is sufficient accuracy..

First 7-8 gallons do not show (on my W with 32g tank) on a stick as the fuel level is bellow the filling port. I would fly to the airport with self serve and do it there, 5 gal at the time. you can interpolate 1 gal mark in between.

 

Now,

I recently installed new fuel gauges (Aerospace logic) that need calibration in 2 gal increments. Emptied all the fuel from tank (other I run dry) by pulling tyhe drain plugs while tanks were grounded, outside the hangar...

It takes time to do 64 gallons 2 gal at the time. Good luck.

 

 

I agree that is a very good system. My airport shut down their self serve pump, and I am reluctant to fly somewhere else and tie up their pump for the length of time necessary for me to play my game. I also agree that one gallon increments is over-kill, but now I think I am likely to do 2 gallons at a time. And my tanks are 37 or 38 gallons each. Still a bit of time.

[kortopates]

Consider these issues. since you are just calibrating a stick for on the ground fuel level, you don't need to level the plane longitudinally - just find a level pad to position the plane.

But to get accurate data you do need to level the wings and prevent the expected change in lateral angle by adding fuel un-evenly to one side only at a time.  very little change in lateral angle moves a lot of fuel inboard or outboard. Its ideal to have the plane on wings jacks and add equal amount of fuel to both wings simultaneously starting at empty + unusable fuel added.

Remember full is technically at the base of the anti-siphon filler neck on the K's.

Monroy tanks add additional considerations since the fuel added to the inboards will move outboard once you are at 1/2 main tank capacity.  Probably best to add all fuel to the outboards and let it migrate inboard - quicker to stabilize than the other way due to an internal flapper valve.

[201er]

Some of the small airport self serve pumps don’t see much action, especially on a weekday. 

[pwhicks]

Don,

I did this with a gallon gas can after tank repair a few years ago.  This is on a ‘79 M20J.  

The stick is the generic stick available from the pilot shops measured from the flat wing bottom.

It took 9 gallons to even have anything to measure.  It took 33 to fill to the lip.

Stick Gauge : Gallons (unusable factored)

1.25 : 9

2 : 11

3 : 13

4 : 16

5 : 19

6.5 : 21

7.5 : 23

8.5 : 25

9 : 27

13.25 : 33

You can see my patience adjusted after I got to the tabs.  

I didn’t do anything special for grounding since I was using plastic jugs/funnels.

 

[N201MKTurbo]

19 minutes ago, pwhicks said:

Don,

I did this with a gallon gas can after tank repair a few years ago.  This is on a ‘79 M20J.  

The stick is the generic stick available from the pilot shops measured from the flat wing bottom.

It took 9 gallons to even have anything to measure.  It took 33 to fill to the lip.

Stick Gauge : Gallons (unusable factored)

1.25 : 9

2 : 11

3 : 13

4 : 16

5 : 19

6.5 : 21

7.5 : 23

8.5 : 25

9 : 27

13.25 : 33

You can see my patience adjusted after I got to the tabs.  

I didn’t do anything special for grounding since I was using plastic jugs/funnels.

 

Plastic jugs and funnels are the most dangerous. Static charges can’t build up on metal (unless isolated) but they can on plastic. Look up the triboelectric effect.

 

You should be using grounded metal containers and funnels.

 

glad it worked out for you.

https://en.m.wikipedia.org/wiki/Triboelectric_effect

[pwhicks]

Me too!


Sent from my iPhone using Tapatalk

[DonMuncy]

Is there any way to ground plastic containers?

[jetdriven]

Safety wire or a test lead clipped to a long extension or a jack handle which is inserted into the gas can. Other end to the plane 

[carusoam]

Expect the static charge of electrons... to be collecting on the outer surface of things... like the jug itself...

So... keep that in mind as well...

On real dry days... and a really big jug... 

Best regards,

-a-

[MikeOH]

This just doesn't sound like a good idea.  The risk is probably small if proper grounding techniques are employed, but I'm not seeing the big return on the risk taken.

Honestly, I'm NOT going to take off if nothing shows on the dipstick (i.e. less than around 10 gallons in a tank).  So, no point in draining a tank for me.  I just waited until I was down to 12-15 gallons in a tank, then marked a line, filled five gallons at the pump, marked a line,...rinse repeat until the tank was full.  Then labeled the lines by subtracting backwards from 32 (M20F full tank).

A dipstick is NOT a precision measuring device, +/- 2 gallons is all I'm going to count on.

[Browncbr1]

Yea, no need to run dry.  Get fuel level to right at bottom skin directly under fuel cap.  Fill and mark in 5 gal increments to the cap lip.  Then, work backwards to deduct the absolute values.   If you need more accuracy than that, I’d take more fuel or plan a fuel stop.  I wouldn’t rely too much on exact gallons, as it changes with temperature.  

[GeeBee]

As someone who was an early owner of a truck bedliner, that caused a gas can fire at a filling station, can (especially poly containers) fueling an airplane scares the daylights out of me. I was not hurt, but it was a close call. My incident in the early 80's was investigated by the NFPA which resulted in the warning stickers you see on the pumps now. Fundamentally unless a portable container is directly on the ground, especially poly containers there is not enough grounding you can do. My container was steel, and in contact with metal on the truck tailgate, but that was insufficient. By the way, when that spark goes off? You see it.

 

 

[steingar]

Why not just fly to someplace with self serve gasoline?  Fill it up 5 gallons at a time until full.  Mark down the level of this stick, and at the end figure out amounts.  Seems simpler.

[bradp]

Reverse methodology is best... note when fuel reaches the bottom of the tank directly below the filler neck.  Not gallons on fuel pump.  Fill up 5 from there.  Mark stick.  Fill up 5 increments until topped off, marking stick as you go.  Now you can back subtract your marks from full on your stick and mark gallons.  Much less risky than toting fuel in carboys.

[JimB]

Being a maintenance guy, I got a 20 ft 3/8" fuel hose from the auto parts store and -6 AN hose barb fitting. Disconnect the fuel line coming out of the fire wall and hook it up there. Use the aircraft pump to transfer the fuel from either tank wherever you want (5 gallon containers or the other wing). Fast and effective. You can drain the bit of unusable fuel out the sumps. Don't run the pump dry

[75_M20F]

On an F, how much gas is left in the tank when the area under the filler area is dry but there is fuel at the wing root area?

[Gagarin]

11 hours ago, DonMuncy said:

Is there any way to ground plastic containers?

Put them on the ground.

[gsxrpilot]

Running a tank dry is a useful exercise as it's the only guaranteed way to know how much useable fuel the wing holds.

And just like we all had to practice stalls at one point in our training, it wasn't because we stall a lot, but so we know what it's like if it does happen or we get close. In the same way, I like knowing what happens when the engine runs out of gas. What the indicators are and what the response is as I switch tanks.

It's not for everyone, and some are certainly afraid, just like some are afraid of stalls as well. But it is a useful exercise for those of us who consider a cross country to be a flight where you stop for fuel and are still outbound.

[Igor_U]

47 minutes ago, 75_M20F said:

On an F, how much gas is left in the tank when the area under the filler area is dry but there is fuel at the wing root area?

7-8 gallons, depending how level you are.

[DonMuncy]

4 minutes ago, gsxrpilot said:

 In the same way, I like knowing what happens when the engine runs out of gas. What the indicators are and what the response is as I switch tanks.

 

On my K, the engine stumbled for about a half second, ran for a few seconds, then stumbled for about 2 seconds. That was enough to assure me it was at the bottom and I switched to the other tank. It took about 4 or 5 seconds of stumbling before it ran smooth again.

[gsxrpilot]

8 minutes ago, DonMuncy said:

On my K, the engine stumbled for about a half second, ran for a few seconds, then stumbled for about 2 seconds. That was enough to assure me it was at the bottom and I switched to the other tank. It took about 4 or 5 seconds of stumbling before it ran smooth again.

A non-event, but now you know. And when you top that tank off, you'll know exactly how much useable fuel that wing holds. 

[MooneyMitch]

24 minutes ago, DonMuncy said:

On my K, the engine stumbled for about a half second, ran for a few seconds, then stumbled for about 2 seconds. That was enough to assure me it was at the bottom and I switched to the other tank. It took about 4 or 5 seconds of stumbling before it ran smooth again.

 

14 minutes ago, gsxrpilot said:

A non-event, but now you know. And when you top that tank off, you'll know exactly how much useable fuel that wing holds. 

Agree. 

[EricJ]

11 hours ago, jetdriven said:

Safety wire or a test lead clipped to a long extension or a jack handle which is inserted into the gas can. Other end to the plane 

I would not recommend that, or at least not rely on that as a suitable ground.    A significant amount, if not most, of the static charge will be on the outside of the container, and for many plastic materials it's just difficult to drain off.   Setting it on the ground will do it, but it takes a while for the charge to bleed off, and that's not useful if you need to pick it up to use it.

Different plastics have different conductivity and some are infused with stuff to make them more conductive.   I've not been able to find out whether typical fuel containers are this way or not, or whether it's enough to help with static concerns.