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Hi all. 84 GMC K3500, 6.2L diesel. Truck didn't run when I got it. Tried ethers, no avail. Some fresh fuel, new glow plugs, glow controller circuit, and new starter later, it started nicely, no smoke. Test drove, kept stalling, and in one instance, gas pedal had no effect on RPM. Sent IP for rebuild. Installed it, truck wouldn't start at all. Started going a bit crazy:

1) cleaned injectors with acetone and brass wirebrush

2) converted Stanadyne canister to spin on filter

3) installed clear lines, hunted down every single air bubble - no more bubbles

4) tried ethers again - did not sound like it liked that at all, so I stopped doing that

5) compression test - all cylinders @ 360-380 PSI, except #7 - makes pressure needle dance before settling at 260-280

6) installed new lift pump

Now engine starts but with a lot of cranking. Blows a lot of white smoke out of both exhausts, and will stall easily. Advancing/retarding pump timing seems to have no effect. Shops in my area don't want to touch with a ten foot pole. Any ideas? Could really use some advice.
 

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Sounds like your glow plugs aren't cycling. These trucks really need the glow plugs to start. Dash light come on for glow plugs?
 
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Sounds like your glow plugs aren't cycling. These trucks really need the glow plugs to start. Dash light come on for glow plugs?
Thank you for the reply! Yes, I see it on the dash, but I also tested for 12V on all plugs. They do get hot.

I can start the engine, and if I let it warm up by keeping on the gas, it can idle, but with so much white smoke it stings the eyes. I might try to change the timing while the engine is running and look for improvements.
 

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I’m wondering if your keyway is partially sheared behind the timing cover.Theres a timing gear that’s placed over the camshaft sprocket that shares the same keyway.The problem with the keyway is that there’s isn’t much “meat” left over for the outer gear to engage upon.That gear meshes with the upper gear that drives the injection pump.This has been known to happen on both the 6.2 or 6.5
 
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Yeah, I'm with 'olds. Might have to pull the timing cover and see if something is funky. Or you have a **** IP
 
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