extra 300

My Feedback: (3)

Hello,

I have a very almost new (only 2 flights, Super Eagle (Gas start) with ceramic plug which has been sitting for about 5 years. Last week i attempted a start and had 2 consecutive successful starts but did not fly.
Today i intended to fly but couldn't get turbine to start successfully, here's what went on:
- Filled on board gas tank with powermax gas (filled the on board tank by turning powermax bottle upside down until flow of gas moving in clear tube slowed down.
- Initiated the start, and although gas was igniting (i could hear it igniting) it would time out before moving to kerosene ramp.
- Noticed that starter would barely reach 5000 rpm (4700/4900 to be exact)
- Temperature reading looked ok and showed an increase but did not go higher than 105 degrees (after 3 consecutive attempts)
- Igniter voltage was initially set at 6.0 volts and was never changed.
- Gas flow was set at 10% and i increased to 12 and then 15%, but this did not help
- after 4 or 5 attempts 2S Lipo still had 75% power..

Finally, i am suspecting a dirty or dry starter O ring and would like to know how can i check same.

Appreciate your advice, input based on above information especially starter speed.
Thanks in advance,

Best regards,

jetmon

Hello extra 300
I dont think it is an starter motor isue, the RPM looks ok for the initial stage
To get it to th the second stage (preheat) it needs a rapid temperature increase, so most likely is related to the amount of gas, try to increase it more, 20% or 30% and try it
Regards

extra 300

My Feedback: (3)

Juan,

Thanks for your feedback. Will try increasing gas as said, but how do you explain that turbine started last week with no issues at same settings i.e. 10%?

extra 300

My Feedback: (3)

one more thing, could it my ECU battery?

RCISFUN

My Feedback: (44)

I would eliminate the on board gas and feed it direct, see post #26 in the following thread, this solve all my gas start issues back in 2007 and I still use this on my Super Eagle.

http://www.rcuniverse.com/forum/jet-...on-solved.html

causeitflies

extra 300

My Feedback: (3)

after a few attempts I was able to have a successful start when I increased gas to 50%!!! I still do not understand how I was able to start it twice last week after a few years sitting with gas at 10%.
Always looking at reasonable explanation to improve the learning process...

will be flying tomorrow and hope all will be smooth.

Regards,

extra 300

My Feedback: (3)

I am glad to report that I was able to do 3 successful flights with the Super Eagle, Turbine started from first attempt on the first 2 flights while for the third one I had to increase again gas to 60%. Is this normal? and how much can I still safely increase the gas flow? is there a particular reason why this is happening? I would very much like to avoid bypassing the on board gas tank...

Thanks again for your help.
Regards,

causeitflies

Are you filling the tank for each start? What is the ambient temperature? Check your gas lines for any kinks or obstructions.

extra 300

My Feedback: (3)

Mark,
on several occasions I removed the one way valve to check if tank was still holding gas and noticed that indeed there was still plenty, ambient temperature was around 30/33 deg. C
On the other hand, gas lines are installed in straight lines with no kinks. I have also checked gas filter and found clear and clean. the only thing I am suspecting the in line restrictor originally installed from the factory as I disconnected the line going to turbine and tried to blow in it and it felt obstructed. I know that restrictor's job is to reduce the flow and inside hole might be extremely small to retain gas and regulate the flow.
Turbine runs flawlessly, (I flew again today) and provide tremendous power and I am very happy with its performance.

I am just trying to figure out the reason behind the need to increase the gas flow.
I read that default value is 80% is this correct? if yes, how come turbine ran with a setting of 10%?

Thanks in advance for your help.

causeitflies

My Super Eagle was in storage for several years and I just started flying it again. I'll check but I think I removed that restrictor. Over time I had problems with starts and PowerMax. After sending it in for service Juan put in the ceramic igniter and changed the percentage to 10%. This was years ago and flying it now I think I had to raise it a couple points. Using straight propane turned on full without a regulator I get perfect starts every time.

extra 300

My Feedback: (3)

Mark,

I have the ceramic plug on mine too but also have the restrictor in line after the filter. Yet setting was at 10% 2 weeks ago when I had the first 2 successful starts after years of storage. issue appeared last week when I tried several starts in vain and then started increasing gas flow drastically.My setting now is at 60% to have smooth reliable starts.

RCISFUN

My Feedback: (44)

As stated before you will get reliable starts every time if you get rid of the onboard tank and switch to propane.
I also brought my Super Eagle out from storage after a few years of sitting, it starts and runs like a Swiss Watch

extra 300

My Feedback: (3)

Hello again,

Back to square one regarding gas starts. Sometimes it works sometime it doesn't. what i will try next time is to hook up to powermax bottle upside down to the on board tank and hit the trigger during start up phase. Would this be a problem? any particular unpleasant expectations should be considered?
Reason i am intending to try the above is for following reasons:
- i do not have propane bottles available locally
- Neither do i have the regulator to place on the bottle....

Thanks in advance

RCISFUN

My Feedback: (44)

The orifice in the restrictor is very small, there maybe something clogging it, when I first had my Falcon many years ago the restrictor was too small, Juan sent me a new one with a larger opening, which also helped with the issues. You could try eliminating it if you will be using the power-max bottle and controlling the trigger.

extra 300

My Feedback: (3)

Rich,

Thanks for the suggestion whoever, i am not feeling comfortable removing the restrictor as there is surely a valid reason for it being there in the first place.
Could i instead hook the powermax bottle to the on board tank and push the trigger during startup without taking the risk of a hot start. mu gas flow setting is presently at 65%.

Thanks

joeflyer

My Feedback: (48)

I had similar issues with my Falcon. The problem is due to the original restrictor being too small. For a while Jet Central was sending out a larger restrictor to customers who complained. I tried drilling out mine; but my smallest drill was too big and then it wasn't starting due to too much gas. My fix was to replace the restrictor with a remote needle valve from an OS91VRDF engine (to the right of the turbine in the attached photo). It worked fine at 1/4 turn open. If it was very hot out I'd have to close it one click. If it was cold out I'd have to open it up one click.

My suggestions are:
First remove the section of tubing that contains the restrictor. Hook it up to your Powermax bottle and blow through it in the opposite direction from your normal flow. This will blow out any dirt or debris. Reinstall and see if that helps.
If that doesn't work find a needle valve and use that instead of a fixed restrictor. Festo and several other companies also make needle valves or air throttling valves that would work.

Joe

jetmon

The amount of gas depends more of the gas valve at the gas bottle, than the restrictor and solenoid adjust
I have seen systems that need to be set at 10% and others near 100% on de same restrictor
The adjustable restrictor that JoeFlyer suggest works well
Also check that the thermo prove end is inside the exhaust nozzle 1/6” or a little more (1.5mm to 3mm)
Regards

extra 300

My Feedback: (3)

Juan,

Thanks for your reply and clarification. in fact I was worried to increase the gas flow percentage but now that you confirmed that it relies on the specific system installed I feel more comfortable. Will check the thermos probe distance and make more tests. unfortunately I do not have access to restrictor or valve locally to try setup.

Rgds

RCISFUN

My Feedback: (44)

You might be able to source a valve locally like the one Dreamworks sells, you could eliminate the solenoid and restrictor if you are connecting directly to the gas source on the ground.

extra 300

My Feedback: (3)

For what it is worth, i think that i have solved the starting difficulties. went down to as low as 5% of gas flow to achieve reliable starts. Turned out that i was way above the required quantity needed to achieve smooth starts.

BTW, very nice and reliable turbine all the way....

Regards,

extra 300

My Feedback: (3)

2 years have passed, jet and turbine have been sitting due to local Country problems and no possibility to fly jets. We have just received clearance to resume flying on a local airport which is great.
I am anticipating a potential problem as i used to have starting issues with the Super Eagle.. My question is could I remove the restrictor completely case I experience staring problems again. I would of course reduce gas flow to minimum 5% or less knowing that the only available Gas is Powermax.
Do you foresee any problems. What could happen?

Thanks in advance

extra 300

My Feedback: (3)

Problem solved. Used a new powermax bottle giving proper pressure. gas flow set to 15%. the trick i found was to let the gas rest in the on board tank for a few minutes before start up and all was smooth.

joeflyer

My Feedback: (48)

The trouble with using Powermax is that the bottle pressure drops as you use it up and you have to make adjustments as the bottle empties. As the amount of Powermax in the bottle would get low I use to park my car facing south and leave the Powermax on the dash to heat it up. If you want to get consistent starts it's best to switch to propane with a regulator That way you'll get consistent pressure as the bottle empties.

extra 300

My Feedback: (3)

Thanks for the advice, unfortunately i cannot get hold of propane locally... At least i know now how to deal with it.