Our 1989 D250 12 valve appears(smells) to be running rich.

250,000 kilometers /155, 000 + miles

Installed rebuilt (had originals serviced) injectors at 100,000 kilometers

Always serviced (oil and oil filter and fuel filter changed every 6000 kilometers and airfilter changed annually). Valve lash adjusted as per Dodge schedule.

Good puff of black smoke on startup, and if you plant the throttle from a dead stop. Sooty tailpipe. Runs clean(appears to visually) on highway. Towed my 8000 lb plus loads last summer fine.

Are there any high mileage issues with timing/ (re-adjusting ) the pump timing at high/these miles.

Thanks

 

Sounds pretty normal for a 12v cummins.

 

I used to be a bit skeptical of routinely running additive, but now I run power service just about every fill up and I have original injectors/pump at 250k miles and it still fires off pretty clean and doesn't smell too bad once it's warmed up. 1st gen VE pumps are a bit different then any 2nd gen pump in how they fuel, the gov. stays open until a few hundred RPMs. Thats what gives a puff of black smoke at startup, and should give a very quick start also.

The parts that were installed for the inj. swap could always be suspect also, if it wasn't a reputable shop/mechanic. But, it isn't abnormal for a 12V to have a dirty tailpipe like stated above.