Injector pop testing

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Re: Injector pop testing

Postby 79Powerwagon » Sat Dec 03, 2016 9:32 am

Tried a new fuel filter, maybe a little less lope (seems to get worse as it warms up) but fuel pressure went to 35psi now. Also have some fuel bleeding out the top of the FSS.
1979 Dodge Warlock, I/C 12v, 518, TCS89% Converter, 6x13 injectors, HE351cw, Piston lp
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Re: Injector pop testing

Postby 79Powerwagon » Sun Dec 04, 2016 1:59 pm

Got a bit more timing out of my pump via rotating. Bumped up idle even more. Still have the lope just not as bad. I can really hear it in the exhaust.

Pulled apart the Piston pump to verify I had all parts in correctly(had checked it for a screen) and it's correct according to a diagram I saw. Still ~30 psi at idle. May have to try another spring?

Odd thing is this all happened after I set pop pressures. Stock nozzles it ran good, then put on the ppump nozzles and it ran a bit worse but not loping, once I set pop pressures it started loping. Seems as if the pump can't handle the higher pop pressures at idle??
1979 Dodge Warlock, I/C 12v, 518, TCS89% Converter, 6x13 injectors, HE351cw, Piston lp
79Powerwagon
fuel screw!!!!
 
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Re: Injector pop testing

Postby 79Powerwagon » Tue Dec 06, 2016 5:45 pm

Well I fixed one thing at least. Found a length of spring that was a bit lighter than the spring in the piston pump. Cut to size and it idles right around 18 psi. Will cut a coil off to get it perfect.
1979 Dodge Warlock, I/C 12v, 518, TCS89% Converter, 6x13 injectors, HE351cw, Piston lp
79Powerwagon
fuel screw!!!!
 
Posts: 295
Joined: Thu Jan 07, 2016 8:59 am
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Re: Injector pop testing

Postby cougar » Sat Dec 31, 2016 10:28 am

2 thoughts come to mind:
1. 5X.016's are pretty big. Even my little 7X.010's needed more timing to smooth out the idle. So jumping a tooth on the gear may be your solution.
2. 300K on the injection pump may be the cause as well. An internal leak may only be noticed at low RPM's. The injection pump not producing enough extra internal pressure to overcome what gets leaked by reducing what the injectors need to work consistently.
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92 W250 HD 47RH with Compushift. Upgraded H1C to 62/60/16, Scheid Lightning VE, 60# valve springs, DAP 7X.010 injectors, 4" DE exhaust, home made cooler tubes.
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Re: Injector pop testing

Postby 79Powerwagon » Thu Jan 05, 2017 5:57 am

cougar wrote:2 thoughts come to mind:
1. 5X.016's are pretty big. Even my little 7X.010's needed more timing to smooth out the idle. So jumping a tooth on the gear may be your solution.
2. 300K on the injection pump may be the cause as well. An internal leak may only be noticed at low RPM's. The injection pump not producing enough extra internal pressure to overcome what gets leaked by reducing what the injectors need to work consistently.



Well I put the stock nozzles back on and it's still loping.

I'm thinking it has to be the pump not being able to keep up with higher pops at idle...

Anyone know what part of the pump may be at fault?
1979 Dodge Warlock, I/C 12v, 518, TCS89% Converter, 6x13 injectors, HE351cw, Piston lp
79Powerwagon
fuel screw!!!!
 
Posts: 295
Joined: Thu Jan 07, 2016 8:59 am
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