Rebuilt HH, now hard start and no idle

[outlaweddeuce]

Hello, i am long time reader of the forum and just now made an account. This is my second M35a2 and I know this would be the place to go for a little bit of help.

I recently picked up my (new to me) Deuce with the lds-465. im unsure on the year but it is in very rough condition. it has been sitting for about 5 years and ran properly when parked. When I got the truck to the house I tried to fire it off and only could get the engine to fire with a few shots of ether.
After some reading and testing, i found the HH plunger must be at fault. i figured that while I am removing the HH that i might as well install new o-rings while I'm there. I ordered a new plunger clip, bow tie gear, and o-rings. once the HH head was removed, I found the plunger and clip had indeed fell off. I completely disassembled and cleaned the unit with no other faulty parts found and lightly lapped the rod and bore. Following the instructions from the board to a T, I reinstalled the HH head onto the truck lining up the red tooth exactly as it was upon removal. After everything was buttoned up and shot of ether the truck fired up back to life!

This is where the story doesn't go as planned. I found the truck would not run under 1,000-1,200rpms and had a haze of white smoke. after letting it run for about 30 minutes hoping it would clear itself out, the symptoms remained the same and also experienced lack of power. I checked the fuel shut off rod and it was moving freely from about 6-7 O'clock to about 5. Checked the injector lines, all correct. turned the fuel adjustment up about 3/4 turn with no change. I wanted to recheck and lined up the timing mark on the crank pulley and checked in the window. the ip timing mark was dead on the money and the red tooth was about 1 tooth to the right of the mark. I did not move the engine during the HH R&R so the IP timing should still be correct. is there any way the HH could still be 1 tooth off? also i have not bypassed the fdc yet to determine if the problem lies in the HH. any and all help would be greatly appreciated! I am at a wall right now

 

[Welder1]

Not sure on your issue but I don't think you should have lapped the plunger to the bore. The tight clearance is how the pressure is generated to pop the injectors. If there is too much leakage with the plunger in the bore most engines won't start on their own but may run at higher rpm. Others may chime in.



Eddie

 

[Floridianson]

Yes when correct the Head will be one tooth off to the rear.https://www.steelsoldiers.com/showthread.php?172002-Injection-Pump-Timing

 

[gimpyrobb]

I wanted to recheck and lined up the timing mark on the crank pulley and checked in the window. the ip timing mark was dead on the money and the red tooth was about 1 tooth to the right of the mark. I did not move the engine during the HH R&R so the IP timing should still be correct. is there any way the HH could still be 1 tooth off? also i have not bypassed the fdc yet to determine if the problem lies in the HH. any and all help would be greatly appreciated! I am at a wall right now

The "red scored tooth" only lines up with the arrow to tell you when the head will be able to be removed from the IP. Period(nothing else).

With the crank pulley lined up, the scribe in the disk of the advance unit(4 bolt window in front of hyd. head) should line up. That tells you the IP is timed to the motor.

The red scored tooth should be VISIBLE ONLY. Visible, but not lined up is correct for what you are looking for.

 

[frank8003]

Also 5 year or older fuel and filters?

 

[outlaweddeuce]

I did not want to use this method, but the plunger was not fully cycling through the bore without binding. I tried to do this as lightly withe finest compound as possible to keep the machine fit.

Is there any way to check the injector pressure to determine if the HH is faulty?

 

[Floridianson]

Just had same problem on another thread and it was the fuel control assembly binding up. Take off the shut down cover and make sure the fuel control assembly that is screwed into the Head move very easy. You can even run the motor with the shut down cover off and shut it down with your finger by just pushing it back to the fire wall or 4 o clock position or as far forward as it will go to start it. Just let it go if it starts or reduce the rpm yourself.

 

[outlaweddeuce]

Well, I got it to idle! I fiddled with it a little bit last night. I bypassed the FDC, dumped a quart of ATF in the tank, and removed and reinstalled the fuel shutoff lever, checking to see if there is any binding(none). I fired it up let it run at 1,200rpm for about 20 minutes and checked to see if it would return to idle and she purred like a kitten at 6-700rpm. It is now very responsive and starts on its own fuel! My only guess is maybe one of the lines i bypassed from the FDC was sucking air or maybe the FDC itself.
I appreciate all the help! now time to start the restoration of the rest of the truck!

 

[Floridianson]

Well checking the fuel control for moving freely is what we want. Now that your FDC is bypass it's just like turning up the fuel and should be very responsive. Get a Pyro installed as you might be able to go more or might need to come down.

 

[gimpyrobb]

Yeah, its really the only way to know when your going to do a lot of damage to the motor.