Filling an LP gas tractor from a nurse tank

I just bought a 720 LP and I am still trying to figure out how to fill the old girl with fuel! Help guys!!!

Do your self a favor and go talk to a pro who worked with LP gas daily. IT can be very unsafe to try to do it with out the correct teaching first and you can freeze a finger off or other parts of the body if you make one simple mistake. ALWAYS wear gloves when doing so and of course never smoke when doing so. It ha been well over a decade since I have done it but I did it a lot when I worked at Tracker Marine with the fork lifts and had more then one frozen glove

Listen to Old!Get proper instruction from a pro...Above all-BE SAFE!!!

There are two ways to fill your tractor. The best is to have a liquid propane pump. This how your delivery truck handles the fuel. The other is the bleed off method. You let the pressure push the fuel from one tank to another. This takes a little skill and you do lose some fuel vapors.

The bleed off method. The tank you are going to be filling from has to have a liquid line to fill with. It just is a line that pulls the propane from the bottom of the tank not the vapor from the top. Most tanks have both fittings.

What you are doing is letting the vapor/pressure push the liquid out through the liquid line. Then on the tractor you are filling you have to open the bleeder to let out the vapor so the liquid fuel can enter the tank. How much propane/liquid you can transfer this way will be affected by two things: 1) how full the main tank is. 2) the temperature this changes the evaporation pressure of propane. The hotter the higher the pressure. You usually can't get the tractor filled to the 80% mark like you would with a pump but you can usually get over 50-60%.

I have filled my grill tanks for years this way. I was terrified the first few times I did it. Now it is not big deal. Handling gasoline is really more dangerous but we just do it more so we are more comfortable with it.

Hook up the hose, (just) crack the vent and turn 'er on. When the vent starts spittin' liquid, you're full.

Hardest part is remembering the counter clockwise thread direction on the hose. :>)

Allan

JD Thanks for the information. I two have a a couple of 100 gal tanks and one has the fill attachment. I was always thinking it was something I was doing in that when I fill the 20 lbs tanks I never seem to get them full. Use them for the grill and goose pit so not you explain I was not doing anything wrong. I always notice the small ones seemed to get filled better when the large tank is full or close.. Have a good day and don,t get to hot, Rain in Tenn last night

Less than 80% is a lot safer that filling too much. Liquid propane expands a lot more than water when it heats up.

I have used Allan's way for years, and my my Dad before me has done it this way. You need to vent some air to make room for the liquid. When it comes out the vent you are full. Like someone else said don't smoke when you are doing this. Stan

It can be done without bleeding, pumping, or pressure differential although I don't know how the new propane valves on the 20 lb tanks will work. I guess you'll have to perform a test to see if liquid will pass through the valve when upside down.

Assuming you have a nurse tank like a 100 pounder, elevate the tank above the 720 tank. Turn the 100 lb tank upside down, attach a hose with the right fittings to both tanks (vapor valve on 720), and let it gurgle in via gravity. It will take a while, maybe over night. You won't lose any vapor or fuel. The 720 tank won't overfill as the vapor valve should be below the highest point in the tank. Don't use the safety device port at the top of the tank. Also don't create a "P" or "S" trap with a hose longer than necessary.