Garrett GTCP 100/54-82 Startup Fuel Pressure??

[scuferrari]

I have been trying to get this Garrett GTCP 100/54-100 running got everything wired so push one button and it should start just like Garrett designed it to but what happens is it lights off at 10% like it should, then it supposed to accelerate up to 35% and starter & exciter turn off but all it does is spin up to about 25% and hangs. so i have now added a fuel pressure gauge between the fuel controler and the injectors for testing but my problem is i have no idea what start up pressure should be, Any one got any idea?? I can't find anything on the web, been googling for 2 weeks. the fuel system is very similar to a Garrett GTP 85,I do know when the fuel shutoff valve closes pressure spikes to 350 psi so i thinking the pump is OK.
CAN ANYONE HELP ME WITH FUEL PRESSURE SPECS PLEASE....

[smithy1]

Can you tell us what EGT's you are seeing when the start "hangs"...if it's low, you may well be suffering from low fuel flow during this stage of the start.

Do you know if it has a "secondary" fuel injection system.??

Cheers,
Smithy.

[scuferrari]

OK found one problem fuel shut off valve was sticking half way closed, fixed that now when starting fuel pressure is 40psi at 0% with boost pump on and climbs to 150psi at 30%. It now lights off at 10% spins right up to almost to 35% and just before the Starter & Exciter should cut out the Acceleration seems to slow and EGT starts going up, from 0% to 30% EGT is 950 deg, from 30% to 34% EGT climbs to 1300 deg and I Abort the Start, there is no fire out the back but looking up the exhaust you can see the flame in front of turbine wheel. 1300 deg on startup this might be normal? if i manually shut the starter off a little early it seems to keep accelerating but EGT is still 1300 deg. it mite cool back down but i don't want to kill the turbine wheel with a over temp. I know my two Microturbo TRI-60s both got 1450 deg on startup everytime, the manual said 1400 was max when starting. And yes there is a secondary fuel system that comes on line when fuel pressure gets to 125 psi and seems to be doing its job i can hear a change as fuel pressure passes that point. I guess what i need to know now is How hot is safe on startup ?
Thanks for any help

[smithy1]

1400F is only ~760C...and should be fine during start, once over the "hump" she'll come back down to normal range....Most turbine engines have a "warm-ish" stage or peak during start. They need the heat to get past the fuel ramp and into self sustain. If your manual says 1400 maximum, I'd stick to that unless you have confirmed information stating otherwise.

I often see ~850C (~1560F) during start of my GT6041 powered machine, she can handle 1000c (~1830F) for short periods but has an Inconel turbine wheel... a lot depends on how much starter/air I give it..once up to idle she drops right back down to ~540C. I consider it normal and has never given me an indication of problems.

Cheers,
Smithy.

[scuferrari]

Great, that's what i was thinking but just not sure, Going to give it a try right now will let you know how it goes. Thank you for the help Smithy.

[smithy1]

Dec 14, 2016 18:29:45 GMT -5 scuferrari said:

Great, that's what i was thinking but just not sure, Going to give it a try right now will let you know how it goes. Thank you for the help Smithy.

Yep....give it a shot and have one eye on the EGT and a hand on the shut-off just in case..!

Cheers,
Smithy.

[scuferrari]

worked great thanks Video of it running www.youtube.com/watch?v=Ez8q1C8IavI