Recent Button and clip re-attachment

[Bloodmike]

Ok, so after quite a while of sitting. I ventured into uncharted territory of pulling the HH and discovering the main issue. The button and clip fell off. Simple enough fix, new clip and o-rings and reassemble, easy enough. Only to find out the droop screw wouldn’t let the fuel shut off to open. Ok, I adjusted that. SUCCESS, truck is running and operating as it “should”. I made a small adjust and turned up the fuel, nothing major. I would start it and drive around the neighborhood with no issues, almost 1 month to the day now I’m having issues. It felt like it was running out of fuel. I put 15 gallons in it just to make sure.1st and 2nd gear run strong same for 3rd as long as the rpms are high. Shifting into 4th the rpms dip and I have the feather the throttle to keep it from dying. It eventually stalls and after a few minutes it starts right up and off we go. I get about 5 to tens minutes of drive time before the issues repeats. Any help would be greatly appreciated. Mike

 

[fsearls92]

Sounds like the hydraulic head on the IP might be in need of replacing. Had similar problems on a few trucks a new or good take off HH fixed it.

 

[Floridianson]

Only to find out the droop screw wouldn’t let the fuel shut off to open. Mike

This has me a little confused. Droop screw and fuel shut off to open? Is your FDC bypassed? Once the FDC is bypassed the droop screw should not be adjusted because it just changes the main fuel setting / twin nuts that we adjust for EGT's. Could you please look through the TM 9 on the IP and see if you are describing the same parts. We have to find out if you are having fuel flow problems or fuel control problems. One common problem is fuel control unit assembly getting sticky or stuck. Then there has been the over tighten of the bridge plate two screws the hold in the fuel control unit assembly. These would be problems with fuel control. Fuel flow/ performance then we change all three fuel filters and bleed system to start. The droop has nothing to do with the fuel shut off.

 

[Bloodmike]

Sounds like the hydraulic head on the IP might be in need of replacing. Had similar problems on a few trucks a new or good take off HH fixed it.

It’s a fresh IP, I had it installed by a service place here in the northeast. It ran for about a month then died. I had to let it sit for a while, now I had time to do some research and talk to a few people. I removed the HH and the problem was found. It ran without issues.

 

[Bloodmike]

This has me a little confused. Droop screw and fuel shut off to open? Is your FDC bypassed? Once the FDC is bypassed the droop screw should not be adjusted because it just changes the main fuel setting / twin nuts that we adjust for EGT's. Could you please look through the TM 9 on the IP and see if you are describing the same parts. We have to find out if you are having fuel flow problems or fuel control problems. One common problem is fuel control unit assembly getting sticky or stuck. Then there has been the over tighten of the bridge plate two screws the hold in the fuel control unit assembly. These would be problems with fuel control. Fuel flow/ performance then we change all three fuel filters and bleed system to start. The droop has nothing to do with the fuel shut off.

I believe it’s a type “G” code injector pump, when removal of the top cover on the back of the pump, it exposes the jam nuts . It’s the rod that pushes the stop plate. It wasn’t allowing the fuel cutoff lever to move past the 6 o’clock position.I’m in the TM9 right now, page 152of 208.

 

[Floridianson]

Okay that makes more sense now but that's not the droop screw. That will be your main fuel control set up on a truck that does not have an FDC. There you will be controlling your fuel for your egts. I would have to look up in the TM but I don't even think you have a droop screw on the G injection pump as I forget the pumps that didn't have one.

 

[Bloodmike]

Okay that makes more sense now but that's not the droop screw. That will be your main fuel control set up on a truck that does not have an FDC. There you will be controlling your fuel for your egts. I would have to look up in the TM but I don't even think you have a droop screw on the G injection pump as I forget the pumps that didn't have one.

It may be my “language “ of said components. Droop screw may not be the correct terminology. However that’s where I am at. It seems to ask for more fuel in the higher gears. Question is, is it a fuel delivery issue or an adjustment issue

 

[Floridianson]

If that's the problem then that would be an adjustment of the fuel delivery system. You said the arm on the fuel control assembly unit was only going to 6:00. Yes we talked about it being close to the 7:00 position. Being at 7:00 position it would deliver more fuel as the collar is covering up the hole/spill port in the plunger longer which would deliver more fuel to each injector. While going by sight or 7:00 is not the best way to set it up I guess you could try and increase the main fuel adjustment till the arm is at 7:00. The best way to get the best performance is going to be installing a pyrometer and you adjust it to your driving conditions.

 

[fsearls92]

It’s a fresh IP, I had it installed by a service place here in the northeast. It ran for about a month then died. I had to let it sit for a while, now I had time to do some research and talk to a few people. I removed the HH and the problem was found. It ran without issues.

Even on rebuilt IP’s they can’t rebuild a HH to my knowledge. I’m going to stick with it has failed, I had it happen on a few of my trucks. They would loose power in the beginning but restart and go again. Then, they wouldn’t want to idle. Just my two cents of what it is. Not going to be adjustments if it was running fine and now it’s not. I would start with changing the fuel filters first before digging deep.

 

[Floridianson]

Just throwing it out there whenever we have performance problems if we still have the problem after all the filters are replaced then we do idle pressure and high idle pressure of the system. At idle the minimum should be 30 psi and at high idle the minimum should be 60 psi