Hoping a guru will read this post. I had a leaky injection pump on my truck so I decided to pull it and put a rebuilt one on. Truck ran great just leaked fuel. I ordered the Scheids 105 lightning pump put it on and was real hard to start. I did bleed the lines. Ran real rough idle, shaking etc. White smoke bad pure fuel out of the exhaust. So I decided to change the injectors with DFI 5X12 sac injectors. No change. I had a brand new Airdog 100 sitting around so I installed that , no difference. So I got reading and decided to advance my timing all the way to the head no difference, Then I pulled my front cover off and skipped a tooth advanced and now starts just like it used to little haze at idle but I expected that from the injectors. Sound great until I hit the throttle then it breaks up real bad Black smoke real bad. Once the turbo lights it smooths out very little smoke and puts me back in the seat. I have a s300g 57/65/14 turbo on it. I do build boost good once turbo lights up. My egts climb fast also with only 4000 lbs load.. Never had much of a problem in mountains with 14000 lbs. My truck is 1992 D250 intercooled automatic Today I put the smoke screw flush with the top in increments no real change and the star wheel was all the way down I put it about 3 threads from the top little change definitely was hoping to get smoother acceleration. Still rough on hard throttle and way too much black smoke. I have driven it about 100 miles since new pump drives good as long as i don't hammer the throttle. Thanks in advance.

 

Do you have any idea what the fuel delivery is? 5x12s seem really big for a stock replacement pump.

 

89-93 Dodge 5.9L Cummins Scheids 12MM Cut delivery valves 4000RPM High Performance VE pump from Pure Diesel Power
Seems like with all the afc adjustment I did it is still flooding the turbo until it lights. I have the stiffer spring also. I am going to try to flip
the star wheel and put it at the top where it while catch the locks and see if that helps.

 

"Flip the star wheel?" Not familiar with that term.

If you don't have the 60lb valve springs tr not to use all that RPM until you do. Keep the valves off the piston tops.

 

Yes I have read it you flip it there is more space it can take up hence tightening the spring for less low boost fueling. I am going to make sure my injector return line is not restricted or clogged also. I already ARP studded and put 60# springs in , thanks for the advice though would be catastrophic without.

 

Reddpup, you have the same IP as mine. They deliver way too much fuel. My timing is set at .4mm per spec. I have to give it a touch of throttle to start it. I have a modified H1C with a 62mm compressor and 16cm2 exhaust housing. I'm in the process of "detuning" the pump to make it more useable. So far, I have reduced the injectors size from 7X.010 SAC to 6X.010VCO. That reduced the smoke some but EGT still too high. Replaced the fuel pin with the OEM pin on the deep side, helped a little more. Cranked up the star wheel while I was in there. Next, I plan to back off on the fuel screw. I have no turbo lag. My biggest complaint is the EGT,

 

Hello Cougar, thanks for the info. I just brought the star wheel as far as I could where it still locks in place and checked for return line restriction. Line are clear from pump and injectors. After reading your reply figured that wasn't my problem. I was thinking the same thing about putting out a lot of fuel. I drove a few miles it cleared up the breaking up almost completely. Turbo lights way quicker still a lot of black smoke and high egts. I am going to follow you to see if you remedy this issue. I sent an email to Scheids hoping they can have some insight. I wish I would of bought a stock pump and tweaked it myself. I do have a stock pin somewhere I am going to change. Maybe mess with the timing a little more. Any suggestions are welcomed for sure. Thanks

 

I use the NON intercooled AFC spring on my '91.5/'93 motors as it is stiffer and helps control smoke a bit.
I got mine from the Hungry Diesel.

With the full tilt boogey pump and 5x12 injectors, swapping in the factory fuel pin would likely help with your EGTs and smoke.

 

Thanks Oliver, I think that is what is in in already the thicker silver spring. Going to order one anyway. I thought I had a stock fuel pin but it's the 2nd Denny T pin.
Do you have any stock not ground fuel pins?

 

Yeah, I think I do have a stock fuel pin in the shop.

I often find when I have the pump tuned where I want it and a HX35 hitting the 35ish PSI top end I really want to see. A stock fuel pin turned to the dark...I mean deep side, does the trick.

I will send you a PM on the pin.

 

Winter has set in, and I have the plow on the truck now. So, I won't be doing any tuning, or should I say detuning on it until next spring. I'm hoping to find a cheaper source for the AFC spring to throw in there than THD, they want more for shipping than the spring. I also have an old M&H M2 pin to try as well.

 

Local Cummins supplier? I would check ebay too. If you get the OEM part number.

 

I have 3 part numbers, but they do not specify their application. 1-464-618-705, or -703, or -651.

 

IIRC the springs are $20. I ordered 3 springs, so I can tune up a few '91.5-'93 trucks. I think shipping was $20-25. Not a big purchase.
Maybe order a few other things you need to help lower the cost per item on the shipping...