Hydraulic head seals replaced and now it doesn’t like to run.

I have been blazing through some repairs to the Whistler the last 3-1/2 years. It started making oil in May of 2015. It sat for a while, the wiring rotted off so I couldn’t get power to the intank pump to check the boost pump seal. Then we had a hurricane. Life got in the way and such.

It now has a new front wiring harness and 3 new o rings on the hydraulic head area. The boost pump drive shaft seal wasn’t leaking. I changed the oil and can get it to run above 1500 rpms only. It is not making oil though. That part is fixed.

Fuel pump in the tank is making pressure. All 3 fuel filters are draining and bleeding clean fuel. It revs up to redline. Pretty quickly too. When it gets below 1500 rpm it will surge and sometimes hold around 1200. Other times it kind of winds down and won’t catch no matter how much throttle I give it.

I have had it running probably 15 minutes since the injector lines were off. I don’t think air in the lines is the problem, but who knows.

Any helpful suggestions?

Thanks and happy new year to everyone.

simple stuff costs zero
Are We sure each outlet of the HH is going to proper injector?
View attachment fuel system best picture.pdf

Yep start with simple. Then timing then we can move to other things and Deuce injectors never need bleeding of air.

Yes, lines are on the correct way. I double checked that thinking the same thing.

Cracked the lines open at the injectors with it running today. I didn’t think it needed to be done. But did it anyway. Each line cracked caused a drop in rpm.

All starts the first day required a shot of ether. Yesterday the first start required ether. Other starts after that just required it to be on the floor. Today it fired up with just flooring it in 40° weather. I was hopeful. We did the line cracking thing and then tried to get it to idle below 4 clicks of the hand throttle. Once below 1000 no matter what I did to the throttle, it would just slowly go down in rpm until it died. All restarts today required ether.

Thinking of the old TM note to drive 100 miles at max gross and see if problem still exist. I took it down the road about 5 miles. Very, very sluggish throttle response and it would hold rpm long after I let off making shifting an exercise in frustration. Excellent power above 2000 rpm and drove great at speed. Colton has to be somewhere this afternoon so we shut down and I got online.

Back to the TM to find what I am missing.

Well if the TM's don't have your answer post again and I will tell you the same thing. Simple first check timing.

Sounds like timing issue to me.

Timing as in we put the HH back on a tooth off?

180 out of time? If the harmonic balancer is lined up, can you see the red scored tooth on the hyd head? The scored tooth shouldn't be lined up, just visible.

1 or 180.

Barrman said:

Timing as in we put the HH back on a tooth off?

Click to expand...

If you fell you have the timing correct lets move to the fuel control. Can you take off the shut down cover off and see where the fuel control is when the engine is off. Should look like about the 7 o'clock position. We can get a hard start if the main fuel is turned down to low. If it is set to low we would take a black magic marker and mark one of the flats. Turn it clockwise 1/2 turn and you don't have to lock the jam nut till you see if it helps on the starting and idle.

Let me go over what we did.

I have a spare IP of unknown condition. I also handed Gimpy tools 5 years ago as he did a HH replacement on Rich’s truck in my driveway. That was my training besides reading about it. So, I lined up the red tooth on the spare IP and removed the HH to practice. It came off and bolted back on. I was ready.

Besides pulling the lines off the IP and HH. Along with using a pry bar on the intermediate shaft while Colton watched for the red tooth. I did the same thing on the truck. The HH came right out. We swapped in round flexible O-rings and put it right back on.

Nothing seemed odd or forced. However, the fuel control rod seemed difficult to move around lining it back up. That is the only thing I can think of that might be different from before. We have cold almost freezing rain today so I won’t touch the truck again until Saturday.

Also, the truck rain great before we started this. No idle issues of any kind. I don’t think the fuel delivery would change without us touching it.

Thank you you all for the help.

I would check fuel pressure at bleeders on filters.

I took the cover off and had only oil in there. That for sure was where I was getting the fuel from before the O-Ring swap. Then I pulled the the clip off the control rod and removed the plunger after clipping the safety wire off again. Every thing looked correct.

Just because I put a screw driver in there and made sure the slot the plunger goes into moved freely. It did. I then put it all back together. The only thing I can point to is the plate that holds the plunger to the pump. We had trouble getting the cover to clear it last week. Today it wasn’t an issue. Maybe, it was on upside down before. I pulled my spare apart and tried it both ways. It didn’t seem to be a difference in anything.

However, something changed. New safety wire on and everything buttoned back up had it running perfect. Well, not perfect. My truck has never started hot or cold without just a touch of throttle. Same way today. Once I let it idle and checked for leaks. I took it down the road for a few miles. Rock solid like it used to be.

Now I have to finish all the wire loom clamps that I let be after getting the wires in place from the harness swap. The brake pedal was soft after sitting so long so I bled the brakes too.

Thanks for the helpful suggestions everyone.

On my three trucks I found giving it a little more droop screw fuel will make them start with a bang as soon as the starter button is pushed.

https://www.steelsoldiers.com/showthread.php?82760-Fuel-screw-droop-balance

I am far away and happy you got the truck going good.
If you use that so called diesel fuel from the gas station then must put
other stuff in there too. A few quarts of new dino oil would help or
homemade seafoam. Don't even put any of that new fangled gasoline in it.

Glad you found it and it was simple. Do believe you removed the fuel control not the plunger and yep you can check for a sticking plunger sleeve with a screw driver. That is why before we install any head we turn it up side down and watch the plunger sleeve move freely on it own till it hits the top. Turn it up right and the sleeve slides back down the plunger with just it's own weight and hits bottom.

DavidWymore said:

On my three trucks I found giving it a little more droop screw fuel will make them start with a bang as soon as the starter button is pushed.
https://www.steelsoldiers.com/showthread.php?82760-Fuel-screw-droop-balance

Click to expand...

If the FDC is bypassed then the droop screw would be the same as the main fuel / twin nut adjustment. It would be easer to do the main fuel adjustment because the piston in the FDC is no longer moving. If the IP had no droop screw but had a smoke cam adjustment it would be the same effect because the piston is not moving any longer. Any adjustment on the smoke cam would be the same as the main fuel adjustment.

And another "Happy customer"
There is no other place in the world with this wealth of information.
I curious how big the SS database is now, has it gone over 500GB?
I could not have fixed my truck without SS people. Thank You all.

Hey Tim, I never thought about it but, Clinto and myself have had a few trucks have running issues if the two screws that hold the fuel control rod are torqued too tight. Not sure why that is, but backing them off a tad worked great. Maybe that was the case here too.