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Discussion Starter #41
Been awhile.
Back to the supply line, if the waste gate diaphragm is ruptured and losing air pressure and it is TEEd to the AFC line there is a good chance the AFC is not seeing a lot of boost and not fuelling up and therefore low power with no smoke. Either change the waste gate actuator or plug the line going to it and see how it drives.
Cheers Steve
Hey Steve, thanks for your response. I tried this and didn’t notice any change. I’m going to try to check for boost leaks now that you mention a leak here would not feed the afc correctly. It got me thinking what if there was a leak preventing boost being built before it hits the manifold?
 

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I still go back to the white smoke & heavy smell of fuel. A fully open waste gate will not make white smoke. Period.
After reading more, it's either timing is really retarded or bad fuel or massive amounts of air in fuel. Any one of these 3 will not make much for heat in the cylinders & cause white smoke ( unburnt fuel ) and be a slug for power.
You mentioned oil in turbo, which actually might be unburnt fuel !!!
 

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Discussion Starter #43
I still go back to the white smoke & heavy smell of fuel. A fully open waste gate will not make white smoke. Period.
After reading more, it's either timing is really retarded or bad fuel or massive amounts of air in fuel. Any one of these 3 will not make much for heat in the cylinders & cause white smoke ( unburnt fuel ) and be a slug for power.
You mentioned oil in turbo, which actually might be unburnt fuel !!!
Thanks for the reply Nascarmark.

I’ve pin timed the pump so unless it can be 180 degrees out and still start and run at idle, I don’t think that’s it. I suppose it could be bad fuel but I put conditioner in it. It seemed to help some as I was able to rev it without the sputtering and missing. I’m holding a bit over 30 psi of fuel right before the injection pump. How would I be able to test for lots of air in the fuel? Even though they were supposedly pop tested when I had them deck and o ring the head, I haven’t quite ruled out the injectors yet.
 

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Selling 4bt & 6bt parts to all of N.America
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K, your good on timing then.
Putting conditioner in bad fuel is only a bandaid. Drain tank, blow out lines etc & put known good fuel in.
You can't see if your pulling in air unless you put a clear line between the filter head & injection pump. I have a test section I made up many years ago.Requires 2 different size banjo fittings & section of clear fuel line. Comes in handy for seeing air in fuel or drain back problems that can show up mins to hours after shut down of engine.
If shop said they tested your inj's, then there is no reason not to believe them, unless something else they did makes you suspect.
 

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Discussion Starter #45
K, your good on timing then.
Putting conditioner in bad fuel is only a bandaid. Drain tank, blow out lines etc & put known good fuel in.
You can't see if your pulling in air unless you put a clear line between the filter head & injection pump. I have a test section I made up many years ago.Requires 2 different size banjo fittings & section of clear fuel line. Comes in handy for seeing air in fuel or drain back problems that can show up mins to hours after shut down of engine.
If shop said they tested your inj's, then there is no reason not to believe them, unless something else they did makes you suspect.
Good point. It’s easy enough to drain it and good peace of mind to know it’s been ruled out.

And with that, I picked up a length of 1/2” clear line and hoping I have enough spare parts from the Airdog to be able to just put it right in line between the injection pump and the current supply line with the push lock fittings.

They didn’t necessarily do anything big to make me suspect other than a couple of very small things: when I asked them that they did pop test the injectors, they hesitated just briefly before saying yes. And the other is that they just gave the injectors back to me in a bag, without caps on the tips, and mixed in with the rocker bolts. Maybe that is ok, but I would have though injectors, especially the tip, should be taken a little more care of?

Thanks again Nascarmark and the rest of you who have tried to/helped.
 

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Discussion Starter #46
I mentioned earlier about the possibility of losing boost pressure before it can build boost(i.e. a leak in intercooler boot/intercooler, or the turbo not building boost), so I decided to test this one to rule it out. I went to Ace and grabbed some pvc couplings and caps, drilled some holes, and hooked it up. Turns out, I only needed the one size(4.5" OD) to fit in the turbo intake elbow. I started with the regulator off and then increased it to 10ish. I could hear hissing but no major leaks that I could hear. I then increased it to 20ish with the same result. Then I increased it to 30ish and could only hear it out the tailpipe. Actually, it seems that is the only place I could hear or feel any air. I could place my hand over the tailpipe and feel it begin to build pressure. I had the mark on my damper at TDC unless it was 180 degrees from TDC. So unless it is crucial to have the engine at TDC, I do not have any boost leaks that I can hear.

My boost gauge had just a bit of a leak at the back of the intake elbow so I replaced the compression bulb on a fresh part of the line. When I pressurized the system, I got a reading on my boost gauge of about 15 psi when I had the air regulator at 20 psi, and a boost gauge reading of about 20 psi when I had the air regulator at about 30 psi. I figured that this was due to the bleed off of air through the exhaust.

Although I was possibly hoping to have a giant hole in the intercooler or better yet, an intercooler boot, I have another test checked off the list.

I'll try to get the clear fuel line installed and the fuel tank and fuel system drained in the next couple of days. At this point, it about HAS to be something with the fuel delivery whether it be air in the fuel, the injectors, the injection pump, or the fuel itself.
 

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Discussion Starter #47
I have some results from some testing. So I actually did a couple of different things this time.

The first test was to drain the fuel system of the old fuel. I drained everything: the tank, the supply lines, and the return lines. The only thing I didn’t drain was the fuel filter and it was recently changed when I was running tests earlier with this issue.

The next thing I did was install the clear fuel line to check the flow of fuel into the injection pump. It looked solid and clear at idle along with at an elevated rpm. Fuel delivery should be ok at this point.

The next thing I did was after the test drive with the new fuel. I noticed my clutch was engaging really late in the pedal throw. I marked how far out the rod was from the cylinder when it was attached to the pedal arm and compared it to the amount of the rod sticking out when the rod is fully relaxed. It looks like I had about 1/4” of engagement on the rod with the pedal fully out. My thought was that maybe there was a constant slight disengagement of the clutch with the pedal fully released. So I added another hole in my bracket attached to the pedal arm and tested it again. Although this still did not solve my no power issue, the pedal engages the clutch much earlier in the pedal throw when releasing the pedal giving it a much nicer and more stock feel.

A few possibilities checked off the list and back to the drawing board. My hunch is still fuel delivery but with just about everything else checked out, we’re down to the unknowns of the injection pump or the presumably pop tested injectors.

One more thing on the last test drive that could be relevant, after I pulled it back into the barn, just as I let it come down to an idle, the engine stalled. I restarted her and she wouldn’t stay running with out just a bit of fuel. It seems every time I test drive her I get in it a bit more each time. Not sure what happened but I haven’t started her back up since. She’s definitely cool now so I’ll start her up and see if she idles now.
 

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Discussion Starter #48
For anyone still interested and keeping an eye on this, we finally have a solution.....

Timing. I am happy that it is finally solved but I am still very confused as to how it was out as far as it was. Firepunk is saying that it only had about 4 degrees of timing somehow! I installed the pump and apparently did not reinstall it in the correct factory time. The reason I am so confused is that when I pin timed it, it was dead on. I havent talked to the mechanic yet but I'm looking forward to talking to him to figure out why this happened.

Either way, the problem is solved and the troubleshooting is over and I have a normal running truck now that I cant wait to drive. They said they put the timing at 17 degrees and when I drove the donor truck, Im sure it didnt have near the power or response that it will have when I get it back.

Hopefully this will help someone else in the future if they run into a similar issue.

Thanks for everyone's help in troubleshooting.
 

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Well I'm glad it is fixed. I knew it had to be either timing or bad fuel ( which will have a delayed flame front ) as mentioned prior. Time to put some miles on it :)
 
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