I have 1992 superduty with 230000 milles and want to install a turbo kit but is there a test to determine if the engine is good for the turbo or it has to many milles for it or is it better to rebuild the engine and install the turbo thanks
If your piston rings don't seal well in the cylinder some of the compression in the cylinder will escape past the rings, especially when the cylinder fires. The pressure/explosion that should be pushing the piston down is being PARTIALLY "blown by" the rings.
The turbo will increase the cylinder pressure that is ALREADY not being sealed in the cylinder & head (combustion chamber) by the piston rings. Hence it will make the problem worse.
One of the members here that has worked on the IDIs more will probably give you some clues on how to tell if you have and how much blow-by. Usually you can see oil in the air cleaner on a gas rig with a PCV valve. I'm going to get my IDI this weekend so I haven't worked on it yet.
You can also have a "leak down" test and a "compression" test done by a diesel/good mechanic.
Changing the head gaskets is a good idea.
If it was me I'd pull the motor, have the heads checked for straightness and cracks,(my Dad has a machine shop and he's seen a few with cracks) maybe even have them decked as little as possible to make them flat, as you don't want to increase the compression ratio since you want to add a turbo.
If your going that far I'd change the valve seals with the std. 6.9L and put in new retainers, basically a complete head rebuild would be good IF YOU WANT TO GO THAT FAR.
What I would definitely do is put a head "stud" kit on it and new head gaskets the other stuff would just be preventative maintainence.
I believe putting head studs in REQUIRES pulling the motor. But just think how easy it would be to put all new gaskets on the motor and install some of the turbo parts. You could inspect the cylinder walls and pistons. Plus depending on what tranny you have you could inspect the clutch, bearings, bushings whatever. If you have an auto you could change the front seal and maybe upgrade the torque converter. You probably wouldn't have to do any major surgery on the truck for a while and it won't bleed all over your driveway.
Personally if my budget didn't alow it (and it probably wouldn't) I'd do all of these things first and get the turbo later. And I would definitely get a turbo, I can't have a diesel without a turbo myself, I'm hooked.
Probably THE MOST IMPORTANT thing is to keep the PH balance right in your coolant. IH (and probably others) sells test strips that will tell you if it's right and the right coolant and/or addatives. If you don't you'll be "sleeving" your block when the cylinder wall(s) get(s) pin-holes (or worse) into the water passages.
This is electrolysis, cavitation or pittig- whatever you choose to call it.
Doge/Cummins
thanks for all the tips, I got my hands on 93 engine7.3 with the turbo in it banks. the problem is that the engine was running fine till the oil plug came loose after a trip to one of those oil change places, the question should I rebuild just the dameged parts bottom end or the whole engine including heads thanks
I'd pull the "92 7.3 and tear down the '93 and use the best of both with all of the other things we discussed. With two motors you have the advantage of already having extra parts like heads etc.
Like Dave said I wouldn't trust the short block if it lost oil pressure and the heads (valves, guides stc.) would be suspect too. But the heads themselves are probably OK if you should need them.
If I assume correctly the '93 is not a factory turbo as I think they were all ATS equipped. The FACTORY turbo motors might have a lower compression ratio which is good if you are going to go with one.
Someone will hopefully set us straight on this.
If it was a FACTORY turbo motor I would have it "sleeved" fully rebuilt, head studded and swap it in at your liesure. And drive your truck the way it is for now, that way you're not in a hurry to get it done, easier on your wallet and and your stress level. I enjoy working on stuff much more if I'm not rushed.
If it's an add-on Banks turbo I would look into using TURBO pistons in the rebuild.
I think it would be worth sleeving the cylinders because if your luck is anything like mine you'll rebuild the motor put it back in and within 10,000 miles the cylinder will fill with coolant! The ones that I have seen go bad were always the back two cylinders, I think usually the passenger's side but I might be wrong on that so don't quote me. Some people cheap out and only sleeve the "bad" cylinder(s) but I'd do them all. It costs about 700-1000 just to do that though.
I don't know what your expectations are for the cost of the rebuild but it's not cheap. I personally think it's well worth it because if you do it right you could very possibly have a truck that keeps up with the new ones and get 3-400,000 miles out of the motor. I'd take a 7.3L IDI turbo built like this over a Powerstroke ANYDAY!
