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starting TIT


rsd653
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Starting tit high more than 850'c of T56-A-7b Eng, ie, we can't go upto 60%rpm just 40%rpm we get 850'c tit and its not cut back tit will go up and up . We already chanch TD valve adjust Fcu,TD AMPS clalibared, blade angle ck its ok. thermocopple and harnes chanch, bleed valve ck its ok. Fuel nozzle chanch,try to start the eng in null position but problem is same. Can anybody help me quickly pl. After fcu change tit was 850 i e more than 20 above from normal rating. "Thanks to all we just over come the problem.

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starter control valve not opening fully, bleed air shut off valve not opening fully, starter

turbine damaged, compressor worn out/FOD'ed, cracked bleed air duct, blown bleed

duct gasket, speed sensitive valve porting air to bleed valves below 94%, TD amp

driving TD valve to PUT condition

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let us assume the starting time is ok!....props blade angle is in ground idle range ok...You've tried it in null!!........rigging is ok!!......could have to deal with an FCU change..What else could it be. ......................the bad John.......................................................I think if I recall.....had that kind of problem many sun arounds!!............Cheers to you guys!!

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I agree with NATOPS1 about the acceleration bleed valves. Disconnect the high pressure out line at the speed sensitive valve which goes to the acceleration bleed valves and see if it starts OK.

I had a bad speed sensitive valve one time which would close the valves at 45% and the TIT would increase rapidly. After shutdown a visual of the acceleration bleed valves revealed they were open because when the RPM droped below 45%.

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Does it mean the herc is grounded because you can't get the eng started within the limits allowed!! I stick with the FCU change. Let me know!!.....You've changed a TD valve so......get this FCU off!!! If I'm wrong, you can kick my ass!!LOL!!!..........John

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Well, lets see FCU change or something 100000000% easier... HUM.... There are so many things that can cause this, so to not do all the easy (cheaper) things first is not the best way to go about it.

It looks like rsd653 has done most of them so...

rsd653 when you say "Starting tit high more than 850'c" how high?

Have you tried to use high pressure air from an engine or just you GTC?

Pj brings up a good point the starter may turn the prop and engine but may bog down due to failure or the starter control valve may be "regulating" the air to the starter at a lower pressure.

When you start the engine how "low" does the air pressure go? At 16% what is the air pressure reading?

22 psi + I would guess as you continue the start until the overtemp.

What RPM do you get to befor the temp goes up? 30 40 or 60%?

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.......are we or should I say ..............are they lining up for an engine change!!!!!........if we talk about engine FOD.

Now!!! We do not have any more feed back! ..............................."Starting tit high more than 850'c of T56-A-7b Eng." So!!.......did you get the engine started !!! .................what are the readings!!!!! My C-130 run up book is at the job right now!!!

But of course it's only a Forum!!!........................why should I worry!!!..................Cheers to you guys................Réj.

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.......are we or should I say ..............are they lining up for an engine change!!!!!........if we talk about engine FOD.

Now!!! We do not have any more feed back! ..............................."Starting tit high more than 850'c of T56-A-7b Eng." So!!.......did you get the engine started !!! .................what are the readings!!!!! My C-130 run up book is at the job right now!!!

But of course it's only a Forum!!!........................why should I worry!!!..................Cheers to you guys................Réj.

You didn't say if you adjusted the Null, to a lower setting.

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Good day jrkaégi!!!. No I never said it because I do not work on Hercs anymore( for now) . I used to be in CAF Trenton. Now I work on aircrafts somewhere else. So!!! to make a long story short!!...........the guy didn't mention any adjusment on the TD valve. Maybe he did. Only "God" knows!!!!! All I feel is that they have an aircraft nailed to the ground because of a Starting temp prob.

So!!!...do we adjust the null!!.......If we do and it do not check serviceable........we do what!!...............Change FCU!!..........If I'm wrong like I said................just come down and kick my ass............very gently of course!!!!!....LOL!!!

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So!!.........what's the score!!! Is it flying or not.......Like the guy said:......"Kick the tires and light up the fires"!!!...............I think they just might have enough fire in the turbine as is!!!!!!...for now!!!............Just blow it out!!!....I'm just a beast!!!

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Could it the 3.5 bleed air check valve, top right aft on engine, be stuck partially open reducing the air pressure to the starter? I worked civillan Herks for 6 years and had about 4 problems with that ck valve. Either stuck partially open, or all the way open. Not all acceleration bleed valves open for the start? The ones on the bottom are famous for sticking due to prop/engine leaks.

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