Attention: TDR Forum Junkies 
RSchwarzli
TDR MEMBER
So, the 1990 was spewing fuel out of the AFC vent. So I pulled the pump, and sent it to a very reputable shop in the area as he has been rebuilding these pumps for over 30 years. He flow tested the unit when he got it from me (23cc) and then replaced the all the seals as I didnt want to half ass this now that it was out.
So he finished the seals, flow tested it again and got the same 23cc, and I got it back. He adjusted nothing, aside from my request to add the 366 spring in that I have had sitting here for a few years as he was in there anyways.
Normal boost for me pre removal, is 45 WOT and about 1400 F with the stage 1 fuel pin (Denny T) that I have been running for a few years. Now with this reinstalled, I am unable to break 30 psi and my pyro is at 1000. So I adjusted the full load screw even though it was returned to the same position I had marked. I turned it in so far that at 1500 rpm, I was unable to hold the rpm there as the rpm would start to run away. I know I was never that far in the past but even with the increase in screwing in, it only gained me 200 F and 5 psi. I checked for fuel pin location and its fine. He never touched star wheel, smoke screw, etc. The diaphragm for the AFC is new about 2 years ago and doesn't show any damage.
I have checked for air leaks to the AFC although my next task is to do a pressure test. But I must admit, I am at a loss.
The timing was set by Bosch dial indicator so I know it is the same. I have good fuel pressure still as I always do (6 idle, 3-4 WOT). Injectors were tested while out for a pop test and all were functioning well. But somehow, I am down a lot of fuel and boost.
Thoughts? I can see I gained rpm by the spring, but has anyone ever LOST power while gaining that rpm? Thats the only thing I can think of! All else is the same. I have pondered that maybe it is boost not pushing the AFC down as that could also be causing lack of fuel, but I will confirm once I have down a pressure test.
Help. I have days into this now and I must admit, I am at a loss.
Robert
So he finished the seals, flow tested it again and got the same 23cc, and I got it back. He adjusted nothing, aside from my request to add the 366 spring in that I have had sitting here for a few years as he was in there anyways.
Normal boost for me pre removal, is 45 WOT and about 1400 F with the stage 1 fuel pin (Denny T) that I have been running for a few years. Now with this reinstalled, I am unable to break 30 psi and my pyro is at 1000. So I adjusted the full load screw even though it was returned to the same position I had marked. I turned it in so far that at 1500 rpm, I was unable to hold the rpm there as the rpm would start to run away. I know I was never that far in the past but even with the increase in screwing in, it only gained me 200 F and 5 psi. I checked for fuel pin location and its fine. He never touched star wheel, smoke screw, etc. The diaphragm for the AFC is new about 2 years ago and doesn't show any damage.
I have checked for air leaks to the AFC although my next task is to do a pressure test. But I must admit, I am at a loss.
The timing was set by Bosch dial indicator so I know it is the same. I have good fuel pressure still as I always do (6 idle, 3-4 WOT). Injectors were tested while out for a pop test and all were functioning well. But somehow, I am down a lot of fuel and boost.
Thoughts? I can see I gained rpm by the spring, but has anyone ever LOST power while gaining that rpm? Thats the only thing I can think of! All else is the same. I have pondered that maybe it is boost not pushing the AFC down as that could also be causing lack of fuel, but I will confirm once I have down a pressure test.
Help. I have days into this now and I must admit, I am at a loss.
Robert
