sidajili

Waoh...I appreciate all the feedback. Will revert parameters to default and try again. Thanks!

sidajili

I set to default parameters according to the manual as below. I am still having the preheat taking too long and fuel flooding the turbine. First try today, the preheat phase was quick and it started, but with a very large flame shooting out. The flame took too long and was going to burn the fuse so I shut down, cleaned out the fuel and tried again. Second try, the preheat was very quick and turbine started. There was still flame almost 3 foot long but it went off quickly so i did not abort. I waited for rpm to stabilize and did a couple of quick half to full throttle runs and then shutdown. The turbine did normal cooling and stopped. I powered off RC, and tried third start about 10 mins later. This time, preheat phase was taking for ever and I see fuel already spilling the thrust tube. I aborted and packed everything up for the day. There is something wrong or something am not seeing. Guys please help me out. I feel there is a setting am missing that can fix this. Really I don't know what else to do now other than assuming turbine does have a problem and needs to go back.

Notes: Aircraft is C-ARF Flash. Turbine is mounted right (glow plug around 1 o-clock relative to aircraft's vertical upright). I am using 3S Li-Fe 9.9v.

Current settings

Start-up Parameters:
Auto +2
Pump Start Ramp 5
Glow Plug Power 7.3V
Low Batt Volts 6.0V
Start Power at Ignit 070
Starter Power at Fuel Ramp 180
RPM 100% Starter Power 15000
RPM Off Starter 19000
RPM to Reconnect Starter 18000
RPM Ignition K 2000
Pump PW Ignition K 23
Engine Min Flow 80%
EGT End Preheat 72°C
RPM Preheat K 5000
RPM Fuel Ramp 10000
Preheat Fuel 28%
Ignit Time Out 30s
Start Mode AUTO KERO

Run Parameters:
Full Power 120000
Idle Speed 33000
Stop Speed 20000
Start Min 100°c
Max temp 852°C
ACC DELAY 008
DEC DELAY 005
Stability Delay 100
Pump Limit 448

bri6672

My Feedback: (6)

Xicoy ECU's are learning ECU's. You should start the motor a few times out of the model on a stand! Mine had a couple hot starts on the bench but the ECU adjusted itself and now they are gone! Took about 4-5 starts.

bri6672

My Feedback: (6)

Also when in doubt call Barry he is extremely helpful!

Midas D.

Again, turn down Pump PW ignition!!! mine is on 15, if i go higher i get flames as well!!

sidajili

Thanks @bri6672 & Midas. I will reduce the Pump PW Ignition and see. Will try value 15 and get back... will give Barry a buzz if this does not work.

mtnflyer14

"When you get flames at switchover, it's usually because pump pw is too high.
If a lower pump pw doesn't seem to work for you, instead of raising it, you should raise preheat fuel %
Raising pump pw increases the fuel sent to the igniter, which won't be able to burn it all, and the unburnt fuel will pool up in the engine waiting for the rpms to spool up (that happens during switchover) and then it will be sprayed outside the engine and ignited. Raising preheat fuel, instead, will send more fuel to the vaporizers, which will be able to burn almost all of the fuel properly, avoiding pooling.

So to sum it up, lower the pump pw and raise preheat fuel"

The above is a quote from another guy on the Kingtech forum regarding a K-100, but he knows a lot more about the start parameters and I think this applies to your problem. My recommendation would be to lower Pump PW to at least 20, maybe 17 or even 15 as Midas suggested. If that does not solve the flame, raise Preheat fuel to 30 or 34. BUT - you have mentioned twice that the flames almost damaged your airplane; perhaps this troubleshooting needs to be done on a test bench out of the airframe?
Regards,
Gus

Midas D.

That's probably the way to go, if it does not start @15, dial up in steps of 1

sidajili

Thank you all for helping out. I changed Pump PW to 15. That did the magic. See the video here.

https://www.youtube.com/watch?v=K7-2ADj35gY I am so happy to get this back ready to fly after over a year of dumping it aside due to this problem. I have a video of the turbine's first start in May 2012:

https://www.youtube.com/watch?v=IRL-6zCAVlg History:
This turbine/jet only had 4 flights since it was built in 2012 for me by my close buddy, who apparently gave up after months of troubleshooting. Revisiting all the unpublished videos made in 2012 (1 flight) and 2013 (3 flights, flown by another friend who visited Nigeria) shows the problem had been there even from the maiden - yes, there was long flame shooting out on first day.

https://www.youtube.com/watch?v=Ho0BNmoMoBI On the 5th flight, it was very bad and I got frustrated and packed up the Jet. I have never had reasons to change parameters in any of my Turbines (K80F on Falcon, K170F on L-39, Jetlegend T12 on Viper).

I blindly trusted the C-ARF Flash build and never bothered to check with Kingtech's defaults for the K140F when I received the Jet. Lessons learned, experience gained! I am so glad this is resolved. Thank you guys!

Midas D.

Happy You, that's good!!

Glad the problem was the Pump PW other wise i would have made an Dildo out of my self LOL

If you get start problems in the near future, cranck up the Pump PW with just 1 sep at a time!!

sidajili

Roger that... Thanks!