6.2 dies when you let off throttle

[Barrman]

Had enough suggestions yet?

I agree with the general theme of this thread. Check as much stuff as you can and if nothing works, do the IP. Everything mentioned so far will only help no matter what the problem is.

When it comes to IP rebuilds. Stanadyne dealers are pretty much your only source unless you find somebody in the military to do it. The rebuild kits themselves are only $50 or so. The costly part is flow testing and adjusting after it is put back together. $350-$500 seems to be the going rate online and at local shops.

I was told just this morning by a fellow worker that a tractor repair place near me has the equipment to flow test Stanadyne pumps. I will pay them a visit and see what price range they think it is worth. You might have some place near you that can do it as well.

 

[86m1028]

Had enough suggestions yet?

Yeah, I was hoping I missed something.

Looks like its going to get a 350 or 454 then.

I cant justify spending $500 on a 6.2.

 

[islandguydon]

Just installed new filter, same issue.

I have been reading them & trying everything.Thanks

All a diesel engine needs to run is fuel & air. My problem was every time I turned off the motor the fuel would back drain to the tank. So I installed a Micro diesel pump from Auto zone. Kipman turned me on to the pump. I wired it so when you turn on the key the pump would start. I installed this at the first hard line break after the tank. PROBLEM SOLVED. The truck cold starts in 3-5 seconds every time since.

Post 36: http://www.steelsoldiers.com/cucv/8...-383-green-carc-rock-slider-installation.html

Hope it helps. Don

 

[86m1028]

All a diesel engine need to run is fuel & air. My problem was every time I turned off the motor the fuel would back drain to the tank. So I installed a Micro diesel pump from Auto zone. Kipman turned me on to the pump. I wired it so when you turn on the key the pump would start. I installed this at the first hard line break after the tank. PROBLEM SOLVED. The truck cold starts in 3-5 seconds every time since.

Post 36: http://www.steelsoldiers.com/cucv/8...-383-green-carc-rock-slider-installation.html

Hope it helps. Don

Don
Thanks for the help.

My truck starts & runs fine until you let off the throttle.

 

[islandguydon]

Take my advise and give it a try. Fuel and air is all a diesel engine needs to run, you have air and not getting fuel. Good luck..!

 

[86m1028]

Take my advise and give it a try. Fuel and air is all a diesel engine needs to run, you have air and not getting fuel. Good luck..!

Don, I do appreciate the help but I dont see how im not getting fuel ?

The truck starts right up, I can hold the pedal to the floor & it will rev till I let off.

BUT as soon as the pedal is released it dies like you turned the key off.
I can hit the key & it fires right back up instantly.

How is this a fuel issue ?

Headed to the parts store for a elec fuel pump as we speak.
Ill give it a try.

 

[Keith_J]

Don, I do appreciate the help but I dont see how im not getting fuel ?

The truck starts right up, I can hold the pedal to the floor & it will rev till I let off.

BUT as soon as the pedal is released it dies like you turned the key off.
I can hit the key & it fires right back up instantly.

How is this a fuel issue ?

Headed to the parts store for a elec fuel pump as we speak.
Ill give it a try.

Engine speed in a diesel is solely controlled by injected quantity. This is a COMMON problem of the governor cutting fuel back completely and not releasing the shut-off when RPM drops. All diesels have governors, otherwise they would not idle. The governor in this injection pump determines governed RPM by the balance of forces between the centrifugal flyweights and the throttle spring. When the accelerator is pushed, the other end of the spring is pulled, causing the spring force to increase and more fuel to flow. When the RPM increases, the centrifugal force also increases. This decreases the fuel.

Now, if the engine is spinning at say 2500 RPM and then you let off the accelerator, the spring force decreases, causing the flyweights to pull the fuel control to zero. And it STICKS closed. Normally, the control opens up at about 1500 RPM and increases as RPM drops.

A rebuilt injection pump is cheaper and easier to do than an engine swap. You know you will need a new torque converter and transmission governor with a swap.

 

[tourus]

My 1028 did the same thing I run a few bottles of 911 though it then run run it the promblem went away try the easyest thing first. put the 911 in a fesh tank of fuel the take the truck out and drive it. atleast try the cheapest and easyest first. then if it does not fix look for other prombles. good luck.

 

[Keith_J]

Chemical cleaning without removal of the injection pump is possible. But even if that fails, the problem is in the governor linkage, not the governor's flyweights. This is easily accessed without pulling the injection pump. Remove the governor cover on the top (item 23 in the PDF below) and check for free movement of the governor arm (item 13 in exploded view). Clean all varnish causing sticking and reassemble. You don't need to go past step 7 of disassembly in the manual below to address the problem

http://www.thetruckstop.us/forum/showthread.php?33450-Stanadyne-DB2-teardown-manual-in-here

 

[brokedown]

My M1009 did the same thing, you could keep it running if you used the gas pedal, but it was really not ideal. This was during the test drive.

After a few miles of running it, it started to improve, and by the time I got it home it was running perfectly. How much driving have you done?

 

[machinist75]

It's a wheel chock, read your pm's. it's an inside joke.