Your white smoke sounds like it could be a timing issue. Shouldn't cost more than an hours labor to have it checked/adjusted. One thing I would do is change the coolant, unless the previous owner mentioned SCA's in the coolant. Do a search for "cavitation" and you will see why this is important. You will want the proper coolant and SCA level if you want the most life from your motor.

Thanks for the reply, I have heard of cavitation, but it was at the back of my mind. I will look into it.

Thanks for the advice.

these engines love synthetic oil .... I've been running 15/40 Royal Purple oil in my truck along with Z-max ... been getting 18+ mpg .... 3.55's and 35" tires ..... pulls good .... another thing to watch out with the coolant ... get a 160* t-stat if you do intend on pulling ... these things will heat up quick if you lug them down on big climbs... ( just fyi )
and most definatly gonna wanna monitor your SCA's for sure...

IMO, that's a great find! After all the basic services, oils, lube, etc, there are a couple little things I'd do. First, have the pump timing checked as stated above. I had an 89 7.3 5spd, 410 ratio that i sold a couple years ago with 285k miles and the best bang for your buck is an after market air cleaner and some exhaust mods. I gained a couple mpgs and got noticeable power gains by doing this. I love my Cummins, but the i.d.i.s are very good runners with little maintenance.

I agree , change the oil regularly , keep you coolant SCA'S in spec, and keep the fuel clean and they will run for a long time ... just don't get tempted to slap on a turbo on a N/A engine ... will be a bad thing

Man, I actually really wish I had a turbo. What is the downfall of putting one on a N/A engine?

Good thing I'm broke as a joke and can't afford one.

I just turned over 200k in my 93 IDI 5-Speed. Timing issue sounds about right. Keep up on the basic maintenance and this truck will serve you quite well for a long time. SnowBiz is right as well. Fix up the exhaust, and mod your air intake into the air cleaner box and you'll notice some decent power gain and a few extra mpg. Awesome truck mate, reminds me of my 87 f250 with a 460. Loved it! minus all the big block maintenance... haha

make sure u check you're SCA levels.