Rod_Hart

My Feedback: (4)

I am having problems with my used PST 600r (5 hours since major overhaul) ramping at startup. It transitions from propane to kerosene but will not ramp passed 30K, temp range between 545-600 C. It started fine last fall. I assume that I have some of the parameters incorrect. I have listed the parameters listed below.

Ramping Values
Adjust Ramp Up Lo 9
Adjust Ramp Down Lo 7
Adjust Ramp Up Mid 6
Adjust Ramp Down Mid 4
Adjust Ramp Up Hi 4
Adjust Ramp Down Hi 4

Adjust Ramp Up
Physical Adjust
Adjust Glow Driver 200
Adjust Start Ramp 45
Adjust Idle Rev 57
Adjust Max Rev 162

I am open to your suggestions. One last piece of info live at slightly over 6000 Ft above sea level.

Rod

Stratotanker

My Feedback: (3)

I had troubleshot similar problems and it is usually something simple if it ran fine before providing ramping values were not disturbed. Is the fuel fresh and water/contaminate free? You can rule out the glow driver if the engine lights on propane. Verify EGT probe is inserted far enough into exhaust cone. Inspect the starter o-ring and spinner and make sure they are clean of contaminates and oil free (wipe with denatured alcohol) also, check that the o-ring is not worn, you can flip it around and see if that fixes the problem. Ensure there are no fuel leaks at front of engine, verify that the fuel lines and filters (don't forget last chance under front engine cowl) are not kinked, clogged or contaminated. You can hook the pump to a short closed loop fuel system and plug it directly to the battery to flush any possible debris from gears and casing(don't disassemble pump, learned that the hard way!!!). Propane flow could also be a cause since the starter is supposed to be dissengaging @ 30K and gas shuts off @ 40K. I went to a manual valve on the propane that I can regulate gas flow as the engine requirements can differ from day to day, it eliminated failed and hung starts almost completely. If the gas and starter are showing disengaged, you can make the start ramp a little more aggressive, just watch the egt and excess flames! Good luck.

Chris

John Casey

My Feedback: (4)

I have seen and experienced issue you have... The PST 600 on ethier the Tems ECU or xicoy/gaspar fadec will hang on the start and fail to ramp up to idle if the ECU battery is marginal, (I think the PST starter design draws more power than the standard bendix, because of the many one way starter roller bearings) if your using a NIMH ECU battery switch to a NEW Nicad as the Nimh pack might not have the extra amps output to push the engine over the top. Most failed starts on mine were either operator error (on the propane) or the battery.....otherwise its been a gem of a engine.

I concur with stratotanker....Going to manual propane control also helped it over the hump and negated any further long time hanging issues.(external bottle plumbed thru the plane straight to the engine with only the check valve between the engine and Bottle) It takes so little propane to light it off, I removed the pst onboard propane valve from the system.

Don't forget ...NOT TO DO... multiple "Dry starts" as the bearings need to get lubed with some fuel between starts. Running on just the propane burns up the " bearing start lube" and eventually the bearings. The pump test feature can be used to lube the bearings prior to another start.(Any excess fuel in the engine does NOT dump as well out the back as it does the front of the engine....which was a nasty suprise)

Hope this info helps get....."Little blue" running... cool.

John Casey

My Feedback: (4)

I failed to see this thread moved to another Pst 600r thread.
the thread continues ... here :

http://www.rcuniverse.com/forum/m_9892736/tm.htm