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Discussion Starter · #1 ·
I have posted earlier about my white smoke issue...I have came to about 1 conclusion. Timing...My gut feeling is the timing advance on the front of the injection pump is acting funny. I have a few spare pumps laying around and was looking at timing device. It wouldn’t take much to just weld it solid and set the timing. Why do you need that advancement device? Most mechanical pumps don’t have them anyhow. Were they for emission reasons? Thoughts?
 

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Discussion Starter · #4 ·
It is very random.. It will be black then come to a stop sign and take off then it is white.
 

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If you're getting air in the fuel it becomes compressible and that retards your injection timing. Leading to white smoke. Becuase instead of the injector lines pushing fuel in real time and popping open the injector it's got a lag.

Check fuel supply to the pump. Pressurising the lines can help find small leaks. But it could be tank pickup.

It is not your timing device. Without your timing device your power will drop like a stone over 2500rpm.
 

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Discussion Starter · #6 ·
I really don’t see how it could be. I hav an airdog fuel pump pushing around 20 psi.I deleted the pump on the side of the injection pump. I also have a fuel sump on the bottom of the tank.Do the p7100 pumps on the 4bt have a timing advancement? I may use a timing light to prove anything.
 

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I really don’t see how it could be. I hav an airdog fuel pump pushing around 20 psi.I deleted the pump on the side of the injection pump. I also have a fuel sump on the bottom of the tank.Do the p7100 pumps on the 4bt have a timing advancement? I may use a timing light to prove anything.
I believe P7100's don't have them. The VE pumped 4BT are I think the only ones that can change dynamic timing.

What's the history of your pump? Any chance it's got internal wear?

How does the engine sound just off idle? Smooth and quiet or crackly?
 

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I really don’t see how it could be. I hav an airdog fuel pump pushing around 20 psi.I deleted the pump on the side of the injection pump. I also have a fuel sump on the bottom of the tank.Do the p7100 pumps on the 4bt have a timing advancement? I may use a timing light to prove anything.
How about putting a piece of clear fuel line in to see if the Airdog is pushing air?
 

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Discussion Starter · #9 ·
The pump was rebuilt by Oregon fuel injection. Only has 3000 miles or so. I had this problem before i had the air dog when it was in my 1500. I thought rebuilding the pump would fix it. It lugs down more especially when the a/c is on. It Runs a little more rough then and a little less power and clouds of white smoke. Very random especially if in slow traffic with idling. There is not a bolt that hasnt been turned on that engine. I have been all thru it...
 

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Has anything been done with the injectors? Have you verified the valve train and base engine are ok? The rocker shaft and rockers can wear and cause similar issues. The advance units on these pumps rarely go bad but it does happen. I have caught them not working correctly by using a timing light with a diesel adapter to verify the timing changes at higher rpm. If the timing doesn't change or jumps around erratically it could clue you in. When you installed the pump what timing method did you use? Flow timing is probably the most accurate when done properly, but it can also be very easy to do incorrectly if you are not familiar with the procedure.
 

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The pump was rebuilt by Oregon fuel injection. Only has 3000 miles or so. I had this problem before i had the air dog when it was in my 1500. I thought rebuilding the pump would fix it. It lugs down more especially when the a/c is on. It Runs a little more rough then and a little less power and clouds of white smoke. Very random especially if in slow traffic with idling. There is not a bolt that hasnt been turned on that engine. I have been all thru it...
Does the engine sound loud and hard like an old farm tractor or smoother and quieter like a petrol (gas) engine?
 

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Discussion Starter · #12 ·
Thanks for all your input. It runs a little more rough maybe. The injectors were just rebuilt. How could the rocker shaft cause random white smoke...
 
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