dos007

My Feedback: (24)

I am new to jets and have 2 questions. Is it best to use butane or powermax? Depending on which you use, if you do not use the onboard tank do you hold the powermax or butane botlle upright or upside down during startup?

KC36330

PowerMax, and it's got a clunk in the can so you hold it right side up.

bevar

My Feedback: (27)

So...if you use a green propane can...you have to hold it upside down when using it?

Beave

highhorse

My Feedback: (2)

no!! u want gas, not liquid !!

bevar

My Feedback: (27)

OK...just checking. I have the Propane set up but have never used it. I'm still using PowerMax.

Thanks,

Beave

Kevin Greene

My Feedback: (85)

Not Correct....When PowerMax exits the can it is a liquid...Which is what you want...As the PowerMax enters the turbine it converts to gas...The clunk it the PowerMax can ensures that it is in a liquid state as you fill your onboard canister..

Kevin

KC36330

you want liquid with the PowerMax but with straight propane you want a gas. the PowerMax is converted to a gas when it goes though the 4mm to 3mm fitting, not inside the turbine.

Kevin Greene

My Feedback: (85)

Not so...At least on all of the JetCat turbines that I have run....The solenoid pulses the PowerMax so you can see the liquid pulses as they travel down the line all of the way to the turbine....At least that is what I've seen...If you do convert to propane be prepared to have the possibility of the lines blowing off of their fittings due to the higher pressures that propane exhibits....Also be prepared to have to adjust all of your start gas parameters due to the differential in pressures....If your turbine calls for PowerMax it is best to stick with it....

I've found that with straight propane if you use it as a gas you had better connect the propane canister directly to the start solenoid and don't use an onboard small canister...Reason being is that I've seen that at times (varies with temperature) there isn't enough gas stored in the small onboard canister for a complete start....With liquid you will have enough gas stored in the onboard canister for multiple starts...Just my .02...

Kevin

causeitflies

If not using the onboard tank, hold the Powermax can upside down to get just gas. Hold the propane canister right side up for just gas.

To fill an onboard tank it is the opposite for both. Some other brands of the propane butane mix besides Powermax do not have a clunk so you would hold those cans upright for gas and inverted for liquid to fill the tank.
You do not want liquid to enter the turbine!

KC36330

On all the JetCats i own the pulsing of the solenoid is simply how the ECU controls the gas flow for start up (it varies depending on if you're bypassed or not), the conversion from liquid to gas is still accomplished at the 4mm to 3mm fitting, you can see it liquid all the way to the fitting in the clear 4mm line, after the step down fitting it's non translucent gray so you can't see inside it, but it's a gas at this point.

i also use only off board straight propane and there is no solenoid used, the only thing I've got between the regulator and the turbine is a pigtail with a 4-3mm Festo and a check valve. it takes once (twice if you're a slow learner) and you are a pro at off board starting with just the regulator and with the 1 lb propane bottle i get hundreds of starts not just 'multiple' and regardless how cold it is outside i've never had to warm or shake hell out of the bottle to get it to fill enough to start.

causeitflies

causeitflies

The conversion to gas should happen in the tank. If you overfill the tank you will get some liquid in the line or a little while filling. Hopefully this will evaporate before getting to the turbine.

highhorse

My Feedback: (2)

OMG folks, re-read the 2-part question which was: When using PROPANE WITHOUT ONBOARD CAN, hold the can upright or inverted? A: Upright, so you'll be passing gas.

So sorry, Kev (by the way, how are you? are U going to the meeting Tuesday? Pm me) and KC....Ur both debating an answer to a Q that was not asked.

That aside, IMO, you are both at least partially mistaken. (isnt RCU entertaining?)

The Powemax is a liquid/gas COMBINATION IN the onboard tank, (like your backyard BBQ) and that is why your engine manuals will ask that you 1) DO NOT fill the tank completely and 2) DO mount the tank vertically (so that it is gassing off and THEN leaving the tank, as opposed to liquid pouring out). As my exhibit #1, note that an overfilled vertical tank or one filled to more than 1/2 and mounted horizontally will produce bangs and pops during startup due to the powermax entering the engine in a liquid form and then not gassing off until it reaches the engine! (Kev, Ed's Euro is an example)You should not be seeing liquid in the lines, I think(?).

Kevin and KC: you have both been at this waaaaaaay longer than me, so maybe I just have no clue what I'm talking about! But I THINK I'm on target here...

Don.

Silver182

My Feedback: (2)

All of you have missed one point that I have found really helps. Notice sometimes when you fill the on-board small tank it doesn't seem to fill properly, and or you don't seem to get as many starts. I've found having a vent port with a ball valve between the tank & the fill port allows you to purge air / gas before / during the fill. Seems to allow a complete fill! Suggested in earlier JetCat manuals.. maybe even the newest manual.
Lee

figueroa

My Feedback: (22)

WOW ,
I still have not figured it out.
I'm switching to Kero-start to avoid all the confusion.

flyinfool1

My Feedback: (2)

I have not heard of using straight butane for starting.
Everyone here has been discussing propane vs Powermax and the original question was butane vs Powermax.

I would like to hear the pros and cons of using butane vs Powermax or propane.
My understanding was that Powermax is a mixture of propane and butane.

I currently have only used Kero-start so it is not an issue yet, but my next turbine will be a gas start.

Jim Cattanach

Word of warning.

Do not use any gas mixture that contains acetone. It will rot the seals in the gas valve. Don't ask how I found out.

dos007

My Feedback: (24)

thanks for the input guys, what did we do before a forum such as this. so if i understand this correctly i will do the following:
Use powermax, no onboard tank, hold the can upside down.
if i use the green coleman can rightside up with no onboard tank.
if i use a onboard tank then reverse the position of each bottle.

causeitflies

Correct!!

Kevin Greene

My Feedback: (85)

I guess that I muddied the waters a little too much, not making myself very clear...This is exactly what I was trying to convey...You want liquid if using an onboard tank...[sm=thumbs_up.gif]

Kevin

jkeze

My Feedback: (36)

I thought the question was always Ginger or Mary Ann

dos007

My Feedback: (24)

Mary Ann

turbotodd

There are two reasons for filling liquid into the on board tank. One is to hold more volume for multiple starts. the more important reason is so the pressure does not change during start up. While the gas is flowing to the turbine the liquid in the tank boils and keeps the pressure the same. Once the liquid is gone the pressure will drop as vapor is consumed. The only thing that will affect the pressure in the tank is if the temperature of the tank itself were to change. My 5 cents.
Todd

gooseF22

my two cents:

I got an air regulator from the auto parts store, and then to the farm store and got a propane tank attachment, then mounted a feed line on the air regulator.

When I start, I rotate the regulator to 60psi and begin the start. with the gage you can see when its done using propane. dial it down to zero and disconnect and you done. Some guys dont like this, but it gives me a perfect start every time, cause the pressure is the same. I know Jeff Holsinger does this too, cause I got the idea from him. It also helps when you are troubleshooting, I used this setup when troubleshooting a behotec setup awhile back. the gage tells the story.

I even use it on the wren where it has a needle valve, but it works so well I got rid of on board tank after it blew up when I tried to fill it on a hot day after propane tank got a little hot.