this might sound stupid but i have a 93 cummins auto and we turned it up and it won't smoke. we really don't want the smoke but just thought that was odd. we rotated the fuel pin turned the starwheel, and turned the smoke screw,(i did the same thing to my 90 5 speed and it smokes like crazy). i was wondering maybe it wasn't building boost or something. could you guys tell me anything, is that how its supposed to be or is something wrong? thanks

 

If it wasn't building boost you would have more smoke. But I have also turned up a 93 and it didn't smoke either. Odd... guess i have the same question you do!

 

i have a 1993 w250 and i did the same and i barely get any smoke?? cant seem to figure this out

 

turn the fuel screw in to near runaway and see what happens. be careful and do some research first though. read the sticky in the 1st gen aftermarket forum

 

The intercooled models have smaller injectors than the non-IC'd ones, so that's part of it. Also, you're running an IC. The cooler the intake air, the better your fuel is going to burn. A more efficient burn means less smoke.
Like Crewcab59 said, add more fuel with your fuel screw. But be real careful not to have it run away on you. And before you go real crazy, do yourself and your engine a favor by throwing a pyrometer at it.

 

x2 on the pyro my firend doesnt know much about diesels and he turned his pump up to much with out gauges and he was fallowing me home one night when we both had a load of hay and when we got to the house and opened the hood his exhaust manifold was cherry red and all warped it was pretty crazy sooo gauges are always a good idea

 

I know a guy that did that and once it cooled all the cast iron pieces in the exhaust system were bright white. I did see an article that mentioned something about '93's having smaller injectors than the rest. It seems like the '93's were an oddball batch. The odo, ignition key, and the transmission tunnel are all different on mine than the other years Ive owned.

 

my 91.5 smokes bad

 

ya my 90 smokes like crazy when i want it to. the 93 is my dads and he might be getting injectors but i need to talk him into getting gauges first. thanks for all the replies and help.

 

would anyone reccommend injectors from a 1990? i have a 1993