Selleri

I bought a used P60 #62xx (in a Boomerang Intro) that used to spend time happily going on gas start(in the UK). I decieded to convert it to kero start as the ambient temperature around my parts is usually pretty low. I've managed a few successful starts but more often that not I don't. When I've gotten it to go it has run happily and everything has seemed to work okay. But I've had trouble repeating those starts. Even doing another start after a successful run and cool down has resulted in a failed starting attempt.

The settings I've changed are the U-accel1 and U-accel2 + installing JetCat 7.4V 2500 mah LiPo and of course the kero conversion changes in the menu.

Earlier tonight I decided to log a few start sequences in order to have some data if someone around these parts might be able to offer me some pointers on the matter
I've now moved the jet to a room that is around 20°C if recalibration of the temp prope is what the doctor orders.

ECU 5.00L
U-Accel1: 0.225
U-Accel2: 0.750
Temperature 10°C

Start 1
Batt: 8.4V
U-pump 0.23
RPM: 5600(54-56 normally seen I wont repeat this below unless it goes outside that range)
OC: LowTemp > 70°C

Start 2
OC: IgnTimeOut

ECU restarted

U-Accel1: 0.175

Start 3
Batt: 8.2V
RPM: Value jumped to 15.2
OC: IgnTimeOut

U-Accel1: 0.200

Start 4
OC: IgnTimeOut

U-Accel1: 0.200
U-Accel2: 0.650

Start 5
Batt: 8.1V
Got to AccelDly stage
OC: LowTemp 65-69°C


Battery recharged, 377 mah needed


Start 1
Batt: 8.4V
Again to AccelDly
OC: LowTemp > 63°C max, dropped down to 55°C and cut out

ECU restarted

U-Accel2: 0.600

Start 2
RPM: Value jumped to 14.2
Batt: 8.3V
OC: IgnTimeOut

U-Accel2: 0.625

Start 3
Batt: 8.2V
OC: IgnTimeOut

ECU restarted

U-Accel1: 0.200
U-Accel2: 0.650

Start 4
Batt: 8.2V
OC: IgnTimeOut

Start 5
OC: IgnTimeOut

Start 6
Got to AccelDly
OC: LowTemp > 52°C


Battery recharged, 455 mah needed


U-Accel1: 0.250
U-Accel2: 0.650

Start 1
Batt: 8.4V
Got to AccelDly
OC: LowTemp > 50°C

While preparing for start 2 I noticed the temperature reading went up to 70°C

Start 2
Heat: 40°C
OC: IgnTimeOut (lot of white smoke)

ECU restarted

U-Accel1: 0.275

Start 3
OC: IgnTimeOut

U-Accel1: 0.225

Start 4
OC: IgnTimeOut

extra 300

My Feedback: (3)

Have had similar problems with my P70 Kerostart which were caused by ECU battery. Try changing it or boosting with another similar pack on start up.
Regards.

Selleri

I was going to try a 2s2p 4300 Duralite last weekend but it was a duff one, I'm hoping I'll get another one this week.

Still this is the LiPo pack Jetcat sells so one would think that it would be enough

What settings do you have on the U1 and U2 parameters?

Carsten Groen

Sverrir,
have you followed the instructions regarding setting the Uaccl1 voltage in the manual ?
I have done that on all my JetCat's, and never had any problems
You have to adjust the Uaccl1 voltage so the fuel just "drips" out of the fuelline (for the keroplug), if too much, you will get flames during startup, if too low, it will abort the start.
It all depends on the pump, there is no "magical unified number" to use, although 0.175..0.225 often is optimal. But your pump has proberly already been running some gallons thru it, so it would be wise to do follow the method in the manual.
I'm using LiPo 2S/2500 mA/H on all my jetcats (have 8 in total, +1 on the way) and it has never failed on me. I normally do 3 flights and then charge. During wintertime, I tend to charge between every flight, it's too cold to fly continously anyway [:-]

Vincent

My Feedback: (61)

Selleri,
Are you sure the fuel is moving thru the kero start line during the ignition sequence, is the the plug lighting and the temp going up during the failed start?? The fuel pump works very slowly during the kero start sequence, way different than gas start so it could just be a bad fuel pump. Your settings look ok to me and you should be getting some good starts. The battery works hard on kero start so try to limit it to 3 or 4 starts with a full charge on that size battery. Leave a little air in the kero start line near the motor, watch it when the valve starts clicking during the start up. If the fuel is not moving then keep adjusting the Unacc 1 up until it does. Don`t play around with unaccl 2 unless you are getting flames out the back , overtemps or slo accl timeouts.
V..

ViperOneNL

Just a reminder, LiPo's dont like cold temperatures (below 10 degrees celcius)

In the summer I can do three starts easy on the 2500Mah Lipo, in the winter I barely get one start. Get a big lipo and make a Y kabel, i.e. plug the ECU battery and the booster lipo parallel and after start remove booster. Never had a problem after that.

Cheers,

Mick

Selleri

Carsten I've checked and set the flow according to the manual, that is around 0.225, was 0.175 on gas. I've got successful starts at 0.225 and 0.250 but not repeatedly, maybe down to the battery although that was in August when the outside temp was warmer I hear you about the cold, 15 minutes at a time are about max before heading inside for a few minutes to get a hot drink. My engine has about 14 hours of run time on gas.

Vincent I've not disconnected the kero start line to see the flow during a ignition sequence, I'll leave a little air next time and see what happens. I'm not seeing the glow plug error and it gets very warm so I'm assuming it's working, any way to be sure if the heat is not enough indication? The temp goes up to about 50-70°C and IgnTimeOut follows. The original U2 value was 0.575 and with that I saw quite a few accel timeouts when I got that far.


Mick I'm taking the LiPo from inside the house directly to the garage(around 10°C ambient temp.) for the starts so I was hoping the cold wasn't an issue. I'm trying to source a 2s2p 4300 Duralite ECU as that should have enough power for the start.


As you might have seen from the above I'm very wet behind the ears when it gets to turbines so any tips and suggestions are welcomed
So a bigger battery might be a wise move before continuing on more runs just to exclude that from the equation?

extra 300

My Feedback: (3)

Selleri,

Noneed to have a heavier/more powerfull ECU Battery in your jet, just make a Y connector and use an external same capacity battery then the one on board which you will disconnect after startup. Works great and keep things light.

Let us know how it works out.
Regards.

Selleri

Well... currently it would cost more to get another battery, from abroad, then try the Duralite that the store here has, and I should be able to carry the extra weight as it would still be under the former NiCd weight I'll keep you posted when I try again.

mr_matt

My Feedback: (10)

Hello,

Also, when you are attempting a start, look to see how far the kerosene has siphoned back in the feed line to the ignitor. If it siphons a lot (and therefore takes a long time to get the kerosene "head" back up into the ignitor) you are going to use a LOT more of the battery capacity.

hope that helps,

Selleri

Turns out the second battery was exactly like the first one
So I decided to make videos of the starting attempts([link]http://youtube.com/sverrirgu[/link]) with the Jetcat battery (as it should(and does), work on occations, no luck tonight though).
On the photo you can see how far the fuel has siphoned since I last started the engine a few days ago. Fuel doesn't to go back into the clear part between starts.

Before start 4 I re-calibrated the temp.
Before start 5 I upped u2 to 0.625 (I know, I know, I promise to stop messing with it)

Start 1.1 - AccelDly > LowTemp
Start 1.2 - IgnTimeOut
Start 1.3 - IgnTimeOut
Start 1.4 - AccelDly > Lowtemp (smoke around plug and out the front)
Start 1.5 - IgnTimeOut (smoke out the back)

Battery charged > 355 mah

For part two I didn't change any settings.

Start 2.1 - AccelDly > LowTemp
Start 2.2 - AccelDly > LowTemp (light smoke out the back)
ECU restart
Start 2.3 - IgnTimeOut (heavy smoke out the back)
Start 2.4 - IgnTimeOut

Battery charged > 305 mah

Not sure if this adds anything to what has been said... maybe the smoke does?... but who knows maybe one of the jet wishperers around here can make some sense out of it, or so I hope as a larger battery will take some time to arrive from overseas

causeitflies

Smoke means no ignition. You should get ignition immediately. Is that an older style kero plug?
Also your starter sounds terrible!

KC36330

i watched the videos and it looks like you're getting ignition at times but not getting flow to the CC during the acceleration ramp. with the main fuel line disconnected from the front of the turbine and using the GSU do you get fuel flow when you select 'purge fuel system' ? it might be your solenoid is sticking.

Selleri

Didn't find that option, can you tell me how to find it?

I did those two, if it was either of them.
> Pump TestVolt (0.500V) gives a steady stream of fuel
> FuelValveTest, when changing to "On" I hear a click from it but no fuel

Fuel from the kero start line comes in pulses.

Selleri

I'm not sure what version it is. It was bought new last August.

Well as it's the only starter I know I couldn't tell Should it be replaced?

KC36330

with the RX power on, press Menu Select on the GSU, use the +/- keys to scroll through till you get to the 'Test Function' menu, release the menu select button, then scroll though that menu with the +/- key till you get 'Purge Fuel System'

while on that selection, press 'Change Value' and it'll turn the pump on and open the solenoid, you should get fuel out of the line you have removed from the front of the turbine (hold it over a container) you can also hold change valve and press +/- to increase/decrease pump voltage for more/less flow.

KC36330

Pics to help...........

Selleri

Ok, that is the same as "Pump TestVolt" on my ECU, so > (0.500V) gives a steady stream of fuel

KC36330

connect a length of 4mm tubing to the Kero input Festo on the front of the turbine and blow into it and see if it's clogged up not allowing fuel to pass into the CC.

KC36330

I'm also curious if you've tried swapping it back to a propane start and seeing if you get a successful start on propane.

causeitflies

The plug appears to be the newest.
The temps shown on your terminal show 40-60 degrees which is very high unless you tried right after a failed start.
When you get good ignition the temps seem to rise well but not quick enough.
I would do as KC suggests and see if you can get a good gas start.

Selleri

I'll try that tonight.

After the failed start I tried again, usually within 30 seconds so that explains the heat.

Guess who asked for the kerostart unit to be installed before the jet was sent over and doesn't have it
I'll see what I can dig up...

Vincent

My Feedback: (61)

Leave some air in the line just like in the pic. activate the start sequence, instead of looking at the GSU look at the air in the kero plug feed line. Listen for the valve to start clicking, the fuel should be moving towards the plug and there should be a low sound of ignition. If there is no fuel moving IT WILL NEVER START. If the fuel is moving and there is no ignition, touch the plug, it should be hot. If its hot then replace the plug. If it is not warm then your ecu has a problem.

If you get ignition and it takes too long to ramp then increase the unaccl 2 a click at a time until you get a complete start without too much flame out the back.

V..

Selleri

If you look at this video > [link=http://www.youtube.com/watch?v=HfQjTj1PNNo]http://www.youtube.com/watch?v=HfQjTj1PNNo[/link] < the bubble goes around 10 seconds into the video, not very clear on youtube though. The plug is hot.

KC36330

there is no RPM increase after ignition, to me that says you're getting NO FUEL in the CC from the primary feed line.