What is the normal EGT for this engine at full throttle?? I was running in 35 degree weather. EGT showed 345C at 128,000 rpm and I had a flame out.

Hi Bob,

Your EGT probe has likely moved out of adjustment... It should idle in the mid-500's and run somewhere in the low to mid-600's at full throttle. The only exception to this would be a damaged thermocouple, which I've only ever seen after prolonged exposure to liquid propane during start-up. This is very unlikely, but if your EGT probe is damaged, the tip should be visibly pitted and deformed. Please check the condition of your probe, then readjust such that the insertion depth is approximately 2mm.

The flame-out was likely due to the EGT dropping below the "shut EGT low" value of 250C This is a software parameter that tells the controller to shut off the fuel pump since the flame has likely gone out, if the EGT probe is set up and functioning properly that is. There is also a "shut EGT High" value of 800C, and an "EGT Hold" value of 760C. If the 760C value is passed, the ECU will try to back off and bring the temp back to normal, but if it passes 800C then clearly something is wrong and the motor is shut down.

If you look at the data from your last shut down, it'll likely say something like 249C and the asterisk will be in position #2, indicating EGT out of limits as the reason for the shut down.

Assuming you have the latest manual
See page 22 for info on the EGT probe placement
See page 19 for more info on diagnosing the cause of a shut down.

The manual is available for download at http://www.pstjets.com/j600.html

Kelly

Hi Kelly,

I'll check the display tonight.

I don't think I've seen more than 465C on any of the runs.

I'll double check the position of the probe.

Thanks again for your help.

Bob

Thanks Bob,

I should add to the above... If the probe's housing is damaged they tend to read artificially high for a given insertion depth; obviously not the case with your engine.

If the probe fails such that the circuit is broken, the GDT will misinterpret it and display 979C. This can be due to a fault in the probe, a broken wire, or a connector that's poorly connected to the lead. I know this isn't the case here, but I've been asked about it a few times over the years so it's probably good info to add for others reading this thread.

Kelly

Hi Kelly,

You hit the nail right on the head

* 249C on the shutdown screen. Looks like the probe got pulled out flush.

Thanks and Merry Christmas!

Bob