Robrow

Anyone have a link to or a hard copy they can scan for me? I am particularly interested in the propane tank filling procedure.

TIA Rob.

jetmodeller

Hi Rob i do not know how this is normaly done but i refill my propane canisters from a normal propane container,first place canister or tank in your case in the freezer for 1/2 hour,invert donor bottle connect tank and turn on tap, liquid will flow into tank,done this for years and never had a problem regards Keith whiddett

Robrow

Hi Keith, yes, thanks for the info, also been doing it for years myself, probably should have made my request a bit more clear. I am assuming the tank would be filled and the gas vented off until the liquid reaches the bottom of the vent valve?

I am after the specific instructions/manual for the JPX propane engines, including tank filling. There must be plenty of ex and maybe a few current JPX owner/operators out there?

I do remember vaguely witnessing one being refuelled many moons ago.

Rob.

martin.lees1

Hi Rob, bill & richard had one for many years they will remember.
There not on RC universe but will be at Elvington next time, or i can
text you Bills Tel No.

Rgds Martin.

Robrow

Hi Martin, no problem, Elvington will do.

Rob.

Jack Diaz

My Feedback: (1)

Rob, I don't have the manual, but still can remember a few thing about those pioneering days.

To fill the tank, you just open the vent valve and start filling normally (with your propane container upside down, so that you fill liquid only), until liquid propane comes out thru the vent. Close the vent first and then the main valve. That's it.



Jack

Tim Redelman

My Feedback: (36)

Yeah yeah like Jack said.....If your using the garden variety propane tank that you would use in the family grill for your supply tank you must turn it upside down like Jack said so that only liquid propane comes out of the fill tube. If your using the Lift truck type tank for filling it will dispense the liquid propane while standing upright. Hook the filling tube to the tank in your airplane/test stand whatever your playing with and make sure all connections are connected adequately. Open the airplane tank valve and then slowly open the valve on the propane jug. After the pressure equalizes you can slowly crack the valve on top of your airborne tank and when it just starts to hiss thats open about enough. When liquid propane starts to exit the bleeder valve on the top of the tank close it. Then close the airborne tanks main valve and then the valve on the propane supply tank. BVM used to sell a fueling setup that let you bleed off the propane that was still in the line but when I ran mine for the first few time I did the BBQ tank deal and just disconnected the line and exhausted it away from me. OBVOUSLY YOU DON'T WANT ANY OPEN FLAMES OR DB SMOKERS AROUND YOU DURING THIS ENTIRE EVENT!!!! Have fun and above all be safe! And always remember what mom and dad taught you..... Stop drop and roll! The JPX was a great way to get into jets back in the day and I had a lot of fun with the while other guys were fighting there turbine of choice...THe best part of the JPX was if it got a bubble in the fuel line it didn't matter in fact while running at full throttle you'll notice that bubbles and liquid are racing to the motor. Very cool back in the day. Also the air start was like getting on your soap box and yelling "IM STARTING MY TURBINE ENGINE CHECK IT OUT GUYS!!" Good times. Have fun.

Tim

Robrow

Great info. Thanks gents.

Just a couple of other technical points...what material was the 6mm? tubing that connects directly to the tank festo type connector?

Looking at legacy pics of these old engines the feed from the tank seems to go to a sort of pre-heating manifold incorporated into the exhaust, then back to what I assume is a throttle valve? Was this to turn the liquid to gas before entering the engine?

Rob.

Tim Redelman

My Feedback: (36)

The tubing was a 6mm teflon tube that was not very flexible. Its the same stuff JetCat used to use at the kero plug only 6mm. As far as preheating thats pretty obvious and I'm not sure it atomized all the Propane or just preheated it. You also had to use a pressure gauge and set what was basically the needle valve to 1.2 bar at full throttle. I believe there was a T in the same line that pressurized the oil tank and that you had to run some variance of 1/2 oz to 1 oz per minute through the motor that I can't quite remember. There was also a needle valve on the side of the motor to adjust that too.

Tim.

Robrow

Thanks Tim, pretty much what I expected, I'll have a look for the 6mm PTFE tubing, it probably needs to be the more rigid stuff because of the 60-120psi propane tank pressure. I have one of the pressure gauges...looks like something off an old steam boiler

Cheers

Rob.