jetjohn

After a lay off from flying, just dusted off a couple of my jets ready for this season only to find a problem with one of the turbines.
Simjet 2300aes which on start up keeps going into cool down sequence. I have two of these units so have plugged working turbine into the others ECU & it still works as normal. Plugged faulty one into good ones ECU & it still shows faulty. So have sourced fault to the turbines inner control. I disconnected the thermcouple & tried it on my Wren & temperature was same as wren & went up when held inbetween fingers. So I assume that is working correctly. Fault light ( flashing red ) goes out if either the glow plug lead is diconnected or if the thermocouple is isolated from the turbine.i.e. if I touch the end probe or body of the thermocouple against any part of the turbine with the glow plug lead attached it goes into fault mode.
Any ideas? or help would be appreciated.
Thank you,
John
p.s. These are both the old style 2002 fadec in silver case with 3 light remote switch system.

Edgar Perez

My Feedback: (13)

Can't say its a similar situation, but I ended up having to solder a capacitor directly into the power lines inside the turbine. Otherwise I was having unexplained shutdowns or getting the turbine stuck at a given RPM. Think it was the 470mF.

jetjohn

Just come back in from the garage after putting it all back together. Same fault as before straight into cool down, then after 3 spin ups the ready light came on so did start up procedure & blow me she fired up perfectly onto gas & then onto fuel,shut it down due to being inside garage.
It did cool down sequence then ready for restart. Started perfectly again about 5 or more times.
Had a break then retried, again straight into cool down sequence but again after 3 or 4 spins ready light comes on & she fires up perfectly.

It seems that the overtemp sensitivity is to close too ambient temp. e.g. as soon as gas fires up within a second or two the fuel pump starts to ramp up.

Question, Inside on the pcb board is the mag sensor plus associated diodes, then there is the connector block for the thermocouple wires & along side it a white block with screw on its side. Is this screw for temp adjustment ???? or for something totally different.

Any help will be appreciated.

Thanks
John

lov2flyrc

My Feedback: (24)

John,
Best solution.... Dump that old, antiquated Simjet ECU! Install a Gaspar (Xicoy) FADEC in it. Problems gone and better performance as well. Never had much luck with those old simjet ECU's (suppose Simjet didn't either since they now use the Xicoy as well)

Ruizmilton

My Feedback: (29)

Agree with Todd, the Xicoy ECU will make your life easier and you will save a ton of weight vs that clumsy, heavy, original Simjet ECU/valves.

Edgar: remember yours already has a Gaspar/Xicoy ECU...

andersaa

John - do you have a dataterminal ?
Please read the rpm under startup. I think you will find your problem there.
If the rpms are fluctating or even not existing, take off the blue front cover and locate the small print inside.
Approx. in the middle (on backside) there is a small black component (rpm sensor) - stroke a magnet over it for 5-10 times.
Assemble all parts and see if that was your problem.

/A

jetjohn

Hi Andersaa,

I don't have a data terminal for the turbine, just the three light system.

I don't think it is an rpm problem.
As I said as soon as you switch the unit on it goes into cool down sequence red & green lights flashing which according to the hand book is a sign of over temp. After it spins up about three times the ready light comes on & it does a full auto start. It seems as though the temperature in the turbine is high even when cold. I am wondering what the white block with screw on it next to the thermocouple connecter block on the small pcb board inside the turbine cover does??

Re Xicoy FADEC, that was going to be my solution if I cannot sort out the original ECU. Unfortunately just been made redundant, so no income, so trying to keep costs down to a minimum & yet still enjoy myself.

Thank you for all the help so far,
Regards,
John

jetjohn

Problem sorted.
Just found that the screw on the block next to the thermocouple connecter is used for calibrating the thermocouple.
Noticed that the vibration from the starter motor is just enough for the little blighter[:@] to turn itself backwards slightly.
Turned it forwards about 10 degrees and all works fine, will reset the value for start up manually, then a dab of paint on the screws head & sorted.

Thank you all for your help,
Regards,
John