Tired IP or Possible Retarded Timing?

YachtTech82

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New development on the truck, moderate amount of white smoke on hard acceleration up to 50ish mph. I went for a drive last night to try and troubleshoot my transmission issues which I don't think there is any now, seemed to shift fine even into OD. Anyway from a stop if you accelerate hard it almost seems to start as a missfire but quickly clears and seems to have decent power up until you let off, but it has a moderate amount of white smoke out the pipe, not black like it was a few weeks ago when we started driving it. Starts extremely well even cold, I don't think it even cranks a full revolution before firing off. Has new moose injectors, new glowplugs and glowplug harness, new return lines, new Holly blue electric fuel pump set at 6psi I believe or that's what holley says there regulator comes set at. No weird noises except for what I think is a lazy lifter, seems to clear up after a decent drive. I have not checked timing, have no tool to check it. I'm thinking about bumping it advance a dimes width this weekend to see if that helps. It may also be just a tired IP, it looked newer than the rest of the engine when I bought the truck so I chose to keep running it and only do the injectors which I later learned on this forum was probably a mistake. It also seems to be getting fairly crap fuel economy, I know it has 35 inch tires and highway gearing but 7mpg calculated?? I think it should be more I. The 11-13 range. I know poor fuel economy can also be a sign of a failing IP or retarded IP. Other than that the engine seems to be running and sounding good. Almost zero smoke on cold start and none at idle.
 

IDIBOBS

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So id dump the electric fuel pump and put the stock one back on. It delivers more fuel at higher rpm’s. 7mog is probably about right with giant tires and high rear end gears. You’re really stressing the transmission. Also your going faster the. Your speedo says and further (more miles) because of the tires. As for the smoke, could be many things.
 

YachtTech82

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Do you think the holley is starving the pump of fuel at high RPM? Seems like it is supposed to keep it steady through the entire power band. Anyway, I used my phone gps speed and it is within 2 mph of the speedo at 45 mph and dead on at 25 so that is definitely part of the fuel economy. I know the timing is supposed to be checked after injectors, a new IP, or every 30kish. So it could for sure be way retarded.
 

miked

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When I bought my 94 Idit last year. I was told they had recently replaced the injectors.

The truck was putting out a lot of white smoke at start up and it never quite went away even when at operating temperature.

The transmission shift points were also badly off.

after driving it a few days I put my timeing light on it and found it badly retarded. I figured it to be in the 10 to 15 degrees atdc.
Got it timed to 6 degrees btdc and the smoke went away completely as well as the transmission started shifting normally.
I figured the retarded timing was causing the pedal to be depressed more to maintain speed throwing off the sensor on the injection pump.

All this to say it would be worth while to get your timing checked
 

YachtTech82

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Held at steady 2k.
Fired her up cold this morning, normal glow cycle and it kicked right off as expected, zero smoke, not even a puff out the pipe. Waited a few seconds for oil pressure to build then increased throttle to 2000. Didn't notice anything abnormal, sounded good, and no smoke.
 

Black dawg

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Timing isnt to far off then. If the timing is retarded much they will miss and blow smoke. Although I should have had you do it with the cold advance disconnected.

A quick test that I do to see if they have enough timing to run correctly, as the spec is just a number that is counting on the advance mech working like it did when new. with the cold advance disconnected and held at 2k after a cold start, they will have just the slightest roughness and smoke if the timing is about right.
 

YachtTech82

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One more thing is the fuel filter. I changed it while going through everything when I bought the truck. The old one was pretty gross, not sure when it was last changed, neither was the old owner. We started running fuel from the aft tank because the sending unit is shot for the mid tank. Not sure what was even in the aft tank but I put about 16 gallons in. If that new filter is getting plugged up it would explain a slight miss and smoke under load. I will drain it tonight and take a peek at it. Water in fuel lamp has not come on but I don't know if it's even working.
 

IDIBOBS

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Do you think the holley is starving the pump of fuel at high RPM?
It may or may not be but the system was not designed with the electric pump. You can’t diag a motor that was designed to run one way and now it has mods that really are just band aids for people not wanting to do basic maintenance. One thing I’ve learned over 35 years of being a mechanic and working on types of classic cars and trucks. Put it back to stock it will almost always run better. Unless your making big changes to hp of the motor just put it back to stock. Same with gears. Cheapest hp and tq to the ground is gears.
 

Black dawg

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It may or may not be but the system was not designed with the electric pump. You can’t diag a motor that was designed to run one way and now it has mods that really are just band aids for people not wanting to do basic maintenance. One thing I’ve learned over 35 years of being a mechanic and working on types of classic cars and trucks. Put it back to stock it will almost always run better. Unless your making big changes to hp of the motor just put it back to stock. Same with gears. Cheapest hp and tq to the ground is gears.
What lift pump do you recommend? So far all the current aftermarket ones are a crapshoot at how well they will work AND how long they will work at all. I have been against electric pumps on these since the mech pump was probably the most dependable part of a pretty dang reliable engine.....these new mech lift pumps are junk.
 

IDIBRONCO

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As many times as he is told, it doesn't seem to sink in. Even 10 years ago, I was the same way, but I realize that parts quality is poor these days so I understand the need to find alternatives. All I've seen for an answer so far is "the ones that my local O'Reilliey's carries". No brand names or anything. If there is a good one, I'd like to know about it.
 

YachtTech82

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It seems most replacement parts are crap these days. Unless you can find genuine OEM parts they are just sub-par. In the marine diesel industry we deal with it every day. Doesn't matter the brand either wether its cat, cummins, voldo, mtu, all the OE stuff is still the good stuff but the moment you find an aftermarket replacement it's a crapshoot.
 
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