Hey Matt,

I had my turbine serviced to have the bearings replaced and ever since I have had nothing but problems. I don't get to fly much anymore and have only flown it a couple of times since the service. When I got it back I had RPM misreadings and Bob overnighted me a rpm board and new temp probe at last years Southwest Fan Fly. Today was the first time I had flown it in about 6 mos. When I got to the field and assembled the plane and turned on the rx the GSU was registering about 250 degrees C. Instantly started cool down mode. I noticed as it thought it was cooling down the temp would drop while starter engaged and then rise back up as starter disengaged. So, I of course power cycled it thinking it was a flake thing and the issue still existed. So I thought to my self maybe the temp probe needs to be recalibrated. I recalibrated and now when you turn on the unit it would start at about 21 degrees C and start cooling off to about 0 to -1 degree C. Ok so now im a lil frustrated. I take the turbine off the plane (kangaroo) pull of the front housing to inspect the TEMP PROBE and reseat. I hook the electronics back up and seems to be doing better this time only dropping to about 15 degrees C. So I put it back on the plane and turned on the plane and it was at 50 degrees C and instantly started declining to about 14 or 15 degrees C. I noticed that if you manually spun the compressor it would change the temp by 4 degrees. By then I had enough and decided to start it.. to see how it would act under some HEAT. It started... went to about 680 degrees on idle.. which is about normal. I ran up the throttle,temps got down into the mid to high 500's and did not seem to be jumping around. I did this a couple of times and was ok with the results. I decided to fly it. All went well. ( 1 short flight about 5 min.) Can you please tell me what is going on.

Thanks
Sean Rushing

Jetfreak -

Sounds a lot like the problem I'm having with my P-70. Mine's just out of warranty, but just shortly after purchase (about the 4th or 5th start) tried a cold start and it immediately went into cooldown. Plugged in the gsu and the temp read over 200-c . . . should have read ambient (around 22-c). After checking all connections, the EGT probe and a lot of messing around, finally got the reading down below 100 and got a successful start. The start was fine, run temps were normal, no erratic operation, idle and full throttle rpm's were right on. The engine ran perfect. After complete cooldown, we checked the temp. reading and it was 0-c. Should have been around 22-c.

I've checked a number of times since before a cold start and the ambient reading is always 0-c until a couple of days ago. It was about 90 degrees out . . . tried a cold start and it went into cooldown again. Checked the temp. and it was reading over 200-c again.

Other than the above, I've never had a hot start, flameout or any other problem with the engine in over 30 runs. Hope Matt has a quick fix for this, but my guess is that it's either a problem in the ECU or a bad EGT probe.

Hi Sean,

I can't think of what whould cause this, other than a damaged temp probe. They are very tricky to install and I am surprised Bob is selling them as a replacement item.

If it was damaged then there is not much you can do but send it in. Sorry for the difficulty and the aggravation.

BTW, I have another idea, I will PM you that one as it requires a change to the ECU.

Let me know how it goes.

Regards,

PS frothingslosh I will send you the same info. Like I said, this certainly sounds like a broken temp probe to me.

Regards,

HI People, I had the same problem with my p80, temp at 200, starter running in cool down mode. when I unplugged the multiplex plug out of the turbine and the temp reading dropped down to about ambient.

What i found was this, the circuit board mounts on aluminium tube spacers as standoffs from the inlet of the engine, I think one of these spacers was clamping down on the track therefor shorting part of the circuit to the frame of the engine and causing temp feedback probs.
I installed an insulating washer under this spacer where it was touching the track and my temp settled down again.

Please comment on your solutions if you had a similar prob,
and MR MATT do you think i may have been in the right track??

One other possiblity I've seen a couple times with erratic temp readings is the data cable. Had one that was all over the place like above. A new cable made it all go away.

Hi Oberon,

No I have not heard of that, but I will check with the factory. I have seen what Rick (Thud_Driver) is referring to. That is the easiest thing to check and does fail sometimes so it is always wise to check the data cable and the connector first.