Hi,

Where I'm just getting into the turbine scene, I need to know the down and dirty about propane.

What should I use?

What so good about the Powermax fuel?

What type of cannister do I want inside my jet?

How do I fill that cannister? and safely?

What type of connectors or fittings?

Thanks,

Jerry

Part of the answer to your questions will depend on which engine you are going to use. Some are intended to be run on plain propane (e.g. the green bottles that you are also popular for camping equipment) ; others should be run on the propane -butane mixture that comes in the silver Powermax cans.

Gordon

Jerry,

The main reason why Jetcat switched to Powermax fuel (way back in 1998) over straight propane was because of the lower pressure. When a model jet sits out in the sun the temperatures inside can soar to over 150 degrees F. , this causes straight propane to exceed pressures that regular Festo and barbed fittings can handle and lines start popping off allowing gas to fill the fuselage of your airplane. Powemax is a mixture of propane and butane, therefore the pressure is considerably less.

If you do a RCU search on the subject, I remember a thread where someone posted a chart showing the pressure vs. temperature differences between propane and butane.


The "cannister" and all of the fittings for the starting gas should be supplied with your engine. If you have bought a used engine I would suggest that you contact the manufacturer to obtain the correct parts for it's particular installation.

Kevin_w thanks for the response on the powermax. So when you buy a Jetcat is comes with the onboard cannister and the valve and fittings for refueling that cannister?

I've got a MW-54(directions say propane or the mixed gas such as powermax) and I'm just wondering what equipment do people use for refueling their onboard propane cannister? And also some safety tips on the refueling process.

I see BVM sells a trigger type valve for refueling, anybody using that?
Wren sells equipment for refueling but its the european equivalent, need to find the US equivalent.

I also see that BVM sells a propane cannister that look like a spring air retract air bottle with the proper fittings for propane.

Thanks,

Jerry

Jerry,
I was in the same quandary with my MW54 as well. I found an old propane torch regulator and valve in my junk box and modified it. I thought about the on-board tank thing for awhile and decided against it. Tony F suggested the set-up shown in the picture and it works great. Basically, I run an aileron extension from the FADEC that is accessible for the start along with the gas line from the engine which has a small quick-disconnect on it. For start, I connect the gas solenoid to the extension and attach the gas. This way you don't have to carry the weight of the tank or solenoid on the airplane.........it works great!............as long as you remember to turn the gas valve on! I bought a whole case of Coleman fuel cannisters at Costco for about $1.80 a piece...........real cheap. I think Home Depot has a Bernz-o-Matic torch for about $25.00 that has a hose on it that could be modified. I saw a plumbers torch that would be easily modified because it had all pipe thread fittings, but it costs in excess of $50.00. I hope this helps.

John

Thanks Cactusflyer. I think I'll do the same setup to at least test run my MW54, but I sure like the idea of onboard propane. Maybe order the onboard propane tank from BVM and use your setup for filling the onboard tank.

Are you using just propane to start your MW54 instead of the mix? Looks like the Powermax fuel is hard to come by this time of year. But for onboard propane the Powermax is the best way to go.

Thanks,

Jerry

Jerry,
Yep, the Coleman fuel works great. It lights off cleanly every time. No sputtering. How are you going to do the initial manual start runs? I rigged-up a switch to run the FADEC off of the same battery as the starter and control the starter separately.

John

Darryl Usher sells the trigger valve as well.

Hey Nony,

Who is Darryl Usher, I'm not familar with him.

Jerry

http://www.acsip.com/~dgu/mod1.html

you will have to scroll about half way down the page for the trigger valve.