Smoking black after new injectors while foot on the gas with a stock setting injection pump.

[73IDIBenoit]

For the longest time I knew my Injectors were starting to fail cuz the smoke has been getting progressively worse, & down on power. Abt 2wks ago I advanced the timing a tad, & it’s been starting better, but recently abt 5hrs ago replaced the injectors with a rebuilt set, & she runs better, but when I put my foot on the gas while driving in any gear I get tons of black smoke.

I was initially thinking that since I didn’t replace the IP with it, or because I need to tune the IP as well. I’ve played with the timing, & it’s helped, but I either need to retard it more, turn down the IP even tho the fuel screw hasn’t been touched, or just replace the IP.

I’d like to try to not have to replace it as well, but I also don’t want to melt my motor.

Truck has 225k & IP was replaced @ 180-190k.

I was gonna try to not have to buy an IP, cuz mine still works, but I’m kinda scared to take the top off of the IP, & risk a runaway.

The truck has always been insanely slow, & was always progressively smoking black more & more then sometimes would take forever to start even if it just sat for 2hrs before advancing the timing on old injectors.

 

[IDIBRONCO]

Your timing is probably still retarded. Pitting new (rebuilt) injectors on a worn injector pump retards the timing because it will need to build more pressure in order to fire the injectors. Your pump also retards it's timing as the internals wear. Lastly, since injectors and pumps wear at the same rate, your pump probably needs to be replaced as well. "Works" is NOT the same thing as "works right".

 

[Jesus Freak]

All that stuff is co-dependant. I suggest going the distance on your fuel system while you're there. Tank to IP, replace what needs to be replaced and clean up the rest.

 

[hacked89]

Your timing is probably still retarded. Pitting new (rebuilt) injectors on a worn injector pump retards the timing because it will need to build more pressure in order to fire the injectors. Your pump also retards it's timing as the internals wear. Lastly, since injectors and pumps wear at the same rate, your pump probably needs to be replaced as well. "Works" is NOT the same thing as "works right".

I agree with your closing comments but by his smoke description it sounds like its advanced? It's also odd that by his description it was advancing itself and not retarding itself

 

[Jesus Freak]

I agree with your closing comments but by his smoke description it sounds like its advanced? It's also odd that by his description it was advancing itself and not retarding itself

That's why he needs to go the distance, shower heads to timing.

 

[hacked89]

Yep but it's always easy just to replace everything you know? That's guaranteed to fix it but not always feasible. I was commenting to bronco that it sounds advanced not retarded. I do agree with both of you the pump sounds like it needs to be replaced by a reputable builder. Its probably one of the internal advance components or governor.

 

[73IDIBenoit]

Later that day I was able to retard the timing a lot, & the smoke went down. But when I accelerate it still smokes black just not a thick ploom, & starts ok, but seems like it needs to be advanced.

Ur yeah ur probably right, it needs a new IP sadly. She runs a lot smoother, a tad bit more power, but the millage is 1/2 of what it was.

I’m kinda new to the mechanical Diesel stuff after owning it for 2yrs then a 95 PSD another 2 before then.

 

[KansasIDI]

I've been around 5 IDIs including my own, and they all seem to puff a bit of black smoke during acceleration. I always thought this was normal??!??!? Perhaps it isn't, but in my experience it seems to be.

After I advanced the timing on my 86 it seems to start quite a bit better, but it dropped a bit in fuel economy... still better than my other truck though.

I can't quite figure out why, but my truck makes lots of clatter on the bottom half of the pedal, but if you increase throttle to the top half, it smooths way out, gets super quiet, and runs way harder. Also not near as much smoking, but it drinks quite a bit more fuel if you put your foot in it.