Was I wrong doing this conversion?

icemanjc1 said:
First off..... Merry Christmas people.
One thing, I get bubbles and foam from the line nut at the injector connector tube no matter what, the main reason I pulled the mechanical lift pump and replaced it with the air dog. Please tell me what I'm missing.


Joel
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Is this problem fixed yet?
 
I replaced my new relief valve with another new one today, helped out a little. Psi went from 27 to 31. Removed the #10 plate and gutted the AFC completely today also, boost went up to 14psi with a little gray smoke(5th gear). It's almost mildly usable now.

72chevy-As far as the foam from the connector nut, I'll check again tomorrow but I'm betting it is still happening.
 
Have the pumps been on the bench just to verify no problems with them? How is the return line setup? OE? I'd set the pop-off on the injectors just to rule it out...
 
You can run the fuel return line into a pan to see if you have air in the system, this is the best method I know of. The engine will never run right with air in the fuel system.
 
Neither pump has been benched. The 215hp pump had been previously messed with before I got it. The 160 seemed rebuilt (still had break offs and paint marks). Ive had them both apart, the 160 seemed tighter. My return line leaves the pump from the relief valve, banjo, then 5/16 line to the tee at the back where the steel return from the head comes down to connect to the tee, then 5/16 back to the tank.
 
72chevy said:
You can run the fuel return line into a pan to see if you have air in the system, this is the best method I know of. The engine will never run right with air in the fuel system.
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I understand that. But would it still idle smooth and not smoke when it's warm? I'll check it out though. I've got a pic the connector tube with slight foam if you want to see it.
 
check the fuel pick up in the tank, you may have rub a pin hole leak in the pick up line.
 
icemanjc1 said:
I get bubbles and foam from the line nut at the injector connector tube no matter whatJoel
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I would say that is your hard start problem, you are sucking air. You need to fix that first. I would try a new line and check the threads in the head.
 
icemanjc1 said:
Neither pump has been benched. The 215hp pump had been previously messed with before I got it. The 160 seemed rebuilt (still had break offs and paint marks). Ive had them both apart, the 160 seemed tighter. My return line leaves the pump from the relief valve, banjo, then 5/16 line to the tee at the back where the steel return from the head comes down to connect to the tee, then 5/16 back to the tank.
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What do you mean you had them apart?

I would verify your TDC, and reset the timing, also reset the pop on the injectors.

Also run the fuel from a closed container and a new fuel line first. That would eliminate the air leak issue.
 
A said before Double check the timing. I thought I had mine set @ 24* 4 times and found out otherwise. It should be running way better than that. With a 175 pump with basic mods and a stock AFC mine feels just as strong as before maybe a little more and I still have VP pop off pressures and a 15psi spring in the airdog with a medeocre set od injectors.
 
Sounds like timing is off and theres air getting in somewhere! The higher pop pressures in the injectors can cause your timing to be off at the tip by as much as 4*. If you think its set at 20 that brings it down to 16*. It should still run fine there but if your original calculation is off then you have a problem.
 
If you are still having the problem, check where your boost line runs to the afc housing. Try and just run compressed air to it from the cab with a tank. You might have your boost fitting in a spot that doesn't have boost. Hope you get it fixed
 
I think the pop off pressures is fairly inconsequential here. I've run injectors at both VP and p-pump pressures (not the conversion injectors like F1's, mind you), and my last set of VP injectors actually run the best. That being said, your injectors may be in rough shape and wouldn't hurt to be refreshened.

Fuel pressure shouldn't be hurting you. I ran mine with the VP setup for months with no ill effects. 18-20psi both at idle and WOT. I am wondering if your airdog is just a pump, or is it a filter/water seperator/de-aerates the fuel? If its just a pump, you could be sucking air in the tank giving you fits at the pump.

How did you find TDC? Never hurts to double check.


FWIW, a friend put a '95 12v into his chevy truck. Engine ran fine before the swap. When he installed the engine, he retimed it to 16 degrees (6.4mm). He checked before he changed it, and it was at something rediculous like 28 degrees. Truck never ran right after that. Even changed the pump to a rebuilt one I had. It would start fine, but around 1500 rpm it would start blowing white smoke and you couldn't get it past 2k rpm. Would pop and break up and the smoke would burn your eyes. Got a set of good injectors put in there (DDP4's), and it was a night and day difference.
 
could it possibly be maybe just the fuel line kinked going into the pump from the airdog and you could be starving the pump of fuel. Either that or maybe the fuel shut off on the pump isn't opening up all the way. Just enough for the truck to run but limit alot of the fuel? I also agree on double checking your timing.
 
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I put the inlet hose from the airdog 150 (w/filters) into a plastic tank and a clear hose on the output. Looks good, no change. Kill lever is all the way off(Towards the front). Fuel pressure is holding at 31. Double checked TDC, degreed the cam. Good, good. So I checked each injector nut, broken each one loose just see how much foam for the tenth time. When I broke loose #2, it would foam for 2 seconds and then no fuel, period. Great, 160 pump is bad (freshly rebuilt my ass!).
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At that point, I'm thinking how much of an idiot I am for not sending off my 887 to get rebuilt. So I sent my 215hp pump to Seth at DPE. He tore it apart, said it had chromed barrels and was flaking off causing a fuel delivery problem. Chances are my other pump had the same problem. He put in new barrels and flat top plungers (much cheaper than the notched ones). I stayed with 12mm plungers because I still want to drive it on the street. Came out to 480cc (181dv), pretty good. It's in the mail, I should get it by Tuesday.
 
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Let me know when you get the 887 pump back on Joel and feel free to hit me up if you have any questions.
 
I've got a question, have any of you drilled out the ends of your injector lines, to match the line inside diameter?

Seth, thanks so much for the excellent job on the pump. Money well spent buddy.
 
getblown5.9 said:
FWIW you can leave a 24v injector pop alone and it will run, but in mine it made it hard to start, due to the higher pressure needed to pop. I lowered the pops on my next set and it starts easier, and revs quicker. i dont know how to describe it but with the higher pop offs the rpm's seemed lazy like it didnt wanna climb. now when you touch the pedal it will shoot up quick. thats the best way i can explain it.
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This is exactly what mine was/is doing. It runs better now with the new pump, but not like it should. It still takes awhile to start but not near as bad as before. I'm not saying it's the fix, but it's the only thing left for me.

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Plus this didn't help. It's kinda fuzzy in this pic but all the holes on the pump side of the lines were only approximately .050"! The line on the right, I drilled out to .072".
 
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