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7.3 diesel swap 90 turbo to 88 non turbo

1994ch

1994ch

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Got a friend with a 88 box truck with a blown 7.3 non turbo (I mean blown!!!) several holes in the oil pan, sheared all the bolts in the crank/flywheel............ but it should have a good IP. So we are looking at a 1990 Ford F250 that is supposed to have a good engine but bad IP. How compatible are these years? The Ford also has a turbo (was not sure if the 1990's came with a turbo or if this one has been messed with) Would having a turbo'ed engine change anything with the IP or make it a more difficult swap? Thanks for any input. Just to make it clear the box truck is the one we are trying to get running.
 
It's all interchangeable.
93/94 were the years for factory turbo idi.
But banks, ats, hypermax, rootamaster, etc were making turbo kits for a long time.
When swapping the pump, don't remove the timing gear tower. Leave it in place.

Sent from my SM-G892A using Tapatalk
 
92.5 was when the factory turbo became an option. My uncle ordered his 92 in 91, he was holding out for a turbo, and the dealer told him the 7.3l idi wouldn't get one, they were holding out until the powerstroke came out. He was PISSED when he seen that a turbo became an option in late 92. He ended up putting a banks kit on his. As to changing the pump, I've never done one, so I wouldn't be of much help there. I would be hesitant to use the pump off ofa blown engine though. In stock form the 7.3l was 180/185 hp naturally aspirated, and that engine should run a long time there. If one let loose, I would be scared the pump overfueled big time to melt one down.
 
They had just bough the truck and were driving it back from the purchase when it blew. They said that it was putting out a good bit of white smoke the whole drive. After an hour or so it blew (said there was a huge cloud of smoke mostly coming from under the hood) oil on exhaust maybe? Then after looking at it they decided to fire it up again just to get it off the interstate (already had a small hole in the oil pan so they knew it was scrap) made it another hundred yards when it let loose again shredded the pan and sheared the output bolts.

I was thinking the temp gauge might of not been working and they were burning oil or coolant and overheated it. I am really glad you mentioned overfueling. Had not thought of that and I assume that could also - and is possibly the best explanation of the white smoke?
 
So we got the 1990 ford parts truck running. Seems to start up ok and run ok......it does not like to move but it seems to be more drive train related (auto transmission) I had to rev it up to get it to go forward, but had no trouble going in reverse (thinking maybe the park brake was stuck? the cable was free and moved with the pedal, but it basically acted like the parking brake was on)

So the PO said that the reason he parked it was that it would often loose power and stall. Also said it could be hard to re-start it when it got hot. Said his mechanic replaced the glow plug relay, fuel filter, and lift pump, more trouble shooting and then told him the IP was bad.

I assume the DS2 pump on it is just about identical to the one on a 6.2, but I still don't have much experience with them so what are the symptoms of one of those IP's dying?
 
Assuming DB2 intended to be written. If it looses power and has hard hot starts:
Clear line on return to ensure no air intrusion. Pressure gauge on tee at input of pump to ensure proper pressure.
Test volume output of fuel from liftpump going into Ip.
Check voltage at tps at idle and full throttle, key on engine off.

When hard hot start occurs, pour cold water onto pump and retry to see if cold water temporarily "fixes" hard start. If so, do not have pump rebuilt- buy a complete new one, the head& rotor are shot and rebuild will be nearly as expensive as new.

Does it have a 'miss' or is it well balanced at idle and all through rpm ranges?

Hold rpm at 500 rpm intervals for 5 seconds each to ensure it is capable. 1000,1500,2000,2500 rpm.
 
99% of the time, a hard/no hot start is a bad ip. Typically referred to as "heat soak."

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Thanks for the input! So if the TPS was bad could that get the transmission in the wrong gear and cause it to stall? I am not sure when they intend to do the swap but I will check those things out.

On the original 88 engine that blew could bad injectors have caused it as well? I could get the injectors tested pretty easily, to test the IP the local shop has to ship it out to their rebuild shop in GA. Basically at this point we are trying to figure out how much money to spend on the IP. They only have one three hour trip planned, then just a little bit of running around here and there, so they could probably live with the worn rotor. But we obviously want to make sure that we do not blow up this engine by over fueling.
 
The 7.3 had thin cylinder walls. Big trouble with cavitation.
The E4OD has a limp mode. It'll start in 2nd gear.

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We used to get some purple cool aid looking stuff from NAPA, when mixed with the coolant, that was suppose to eliminate cavitation on the cylinder walls.
I do not remember the name of the stuff.
We would also use test strips to make sure it was up to strength.
 
TPS tells transmission to hold a gear longer or to shift a little sooner. Think full throttle up a hill, you want max rpm before each shift vs. putting down a road you want top gear asap and soft shifts getting there.
As for a "wrong gear" not exactly.

No way should it cause a stalling issue. Something else is going on there. That's why check the other stuff, and we go from there.

I would take my time and do all diagnostics before yanking that IP. You don't need to send it in for testing- you can determine on the engine if it is toast or not. And if they can deal with hot start & poring water on it to start it- not a lot worse than that usually unless it is sucking air through it's seals.
 
MrMarty51 said:
We used to get some purple cool aid looking stuff from NAPA, when mixed with the coolant, that was suppose to eliminate cavitation on the cylinder walls.
I do not remember the name of the stuff.
We would also use test strips to make sure it was up to strength.
Click to expand...
You can get sca/dca additive.
Or run something like fleet charge. It's a pink color, but already has the sca in it.

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Yep, the 7.3l idi often sufferred cavitation, many times to the poi,t it would eat through the cylinder walls, and hydrolock the engine. This could be what happened to yours, and would explain all the white smoke.
 
Got the truck running and drove it around at work (big parking lot) If I put the shift lever in 1st it would start in first but if I left it in drive it would start in 2nd. Not really worried about that though because the box truck is a stick shift...

As far as the engine goes we could not get it to die, does not have air in the return line, seemed to start up ok even hot, so am not sure what the PO was talking about. (not saying that I have full confidence in it..............) Forgot to do the RPM test that Will recommended, so that will have to wait until after the engine swap cause I think that they started pulling it over the weekend.

It does pour out black smoke when stomped on.... and has a lot of blow by.... but cannot seem to see anything wrong with the fuel system. Seems to be mostly transmission problems and (if the gauge is accurate) boost problems as it only shows about 2 psi when floored.

I don't think that they have checked the LP pressure yet but I am going to remind them to check that once they get the engine swapped over to the box truck.
 
Remember, revving in neutral doesn't put a load on the engine, so you won't see much boost like that.
To be on the safe side, you want to keep boost under 12psi anyways. Unless you wanna go in and do head studs.

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