You could also check the small boost line to your AFC...Make sure that small pipe hasn't split or fell off...

 

I havn't had a chance to check the pressure. I'm going to order a new overflow valve from ebay. I already played with the old one once. If I still got the problem after that and anew fuel filter, Then I'll start to investigate further.

 

Can someone explain how the governor arm is suppose to interact with the fuel plate? I had the AFC off today just to going over things and I found that when I pull the throttle to 3/4- full open, the governor arm will touch the plate and then pull back off the plate about 3/8".. I have a 0 plate 7/8th forward. I think the governor arm is suppose to stay in contact with the plate, Correct ? If it is.. then this could be my de-fueling problem over 1/2 throttle. When the arm pulls off the plate the fuel cuts off... Am I on the right track or is this wrong. If I am right, How can I adjust the arm to stay on the plate at full throttle??

 

The arm will only stay in contact with the plate when the shutdown solenoid is in the run position.
Turn the key on and lift it up.

 

I have a cable kill and it was up..or in the run position...
I even disconnected the cable to ensure it was fully open..

 

With the solenoid up (or cable) and a good bit of throttle the arm should contact the bottom edge of the plate if it's adjusted right.
As the rpm increases the contact point goes further up the plate.
Of course the engine needs to be running for that.

 

The arm does make contact on the bottom of the plate.. but when the throttle gets to about 75%, the arm will come off the plate.. 1/4- 3/8th inch back.. Defueling the pump I assume...

 

I think it has more to do with the governor springs not spinning if the engine is off.
As long as the arm starts off at the bottom and doesn't try to dive under the plate you're fine.

 

If you think it maybe the governor..The best test would be to remove the plate and test drive the truck...This would elimate any plate/ governor problem..

 

Ok.. So let's say it's not the governor or a fuel pressure problem.( I'm waiting for the new OV to arrive) What else could it be? It's definitely not a boost problem.. The engine will sputter and won't rev anymore at about 50% throttle at any boost level.

 

Give us a breakdown of what you have replaced on the motor beside the OV.Has the LP been replaced?Your best check for fuel pressure problem is to install a fuel pressure gauge....I see you have a 95..Is this the orginal IP or was it replaced in the past.Even a fuel switch that is not opening fully will cause problems(mostly poor power and no smoke).

 

Well Well...Changed the fuel filter and 40 psi and smoke! I had to cut the old one open to see what it looked like inside. It had about 10,000 miles on it...but Jeez.. This is ridiculous.. My fuel filter was just about clogged with a black, thick, resin type, tar substance... Filter was a WIX. I am using Baldwin filters now and will be doing the fuel filter every oil change !! Thanks for the help guys ! I think I need a bigger turbo...

 

If your main filter was that clogged you should plan on cleaning the prefilter.

 

Yea, I'm gonna do that prolly next week when I got the time. I am curious to see inside there also. I did clean it the last time I did the main.