Hello! First post. Been a lurker for a few years, but not in the IDI section of things.
Bit of a backstory here. Earlier today I bought a 1991 f350 eclbd - with something of a confusing past. I really just bought it for the back bumper and the dually fenders, so if this motor doesnt work out it's alright.
After talking to the guy that had it, he said they had originally bought the truck in 1999 and it had no motor. They added a 7.3 IDI to it, and used it for a number of years, until it broke down and sat. The engine was "rebuilt" and then sat for a few more years. Then this guy started driving it around as a welding truck, said it ran great and took him about 40 thousand miles. Then, it started overheating. He had some hole in the wall mechanic work on it, he just replaced the thermostat. Then, a new problem arose. It would start loosing coolant. Coolant in the tailpipe, little in the oil. I figured it was either head gasket or cavitation, most likely the latter. However, as I pressed him for more details, he claimed that the motor rebuild was a 6.9 block they had put 7.3 heads on. I've searched and searched on google, and found one person who claimed that they did this, and a hundred others that said it couldnt be done. If it is in fact a 6.9 block, that would rule cavitation out, correct? I havent done any of the tests, I want to know what I am dealing with before I start. So anyway, to the gist of my post here. How would I go about determining if it is, in fact, a 6.9 block with 7.3 heads? If I can fix this truck up rather cheaply, that would be a much better alternative to idling my 97 7.3 all day at the ranch. Thanks, and sorry for the long winded post!
To add to this, the starter,or solenoid is out in some capacity. Try to start and it just clicks, all power goes out. Turn off and back on, power comes back.
Bit of a backstory here. Earlier today I bought a 1991 f350 eclbd - with something of a confusing past. I really just bought it for the back bumper and the dually fenders, so if this motor doesnt work out it's alright.
After talking to the guy that had it, he said they had originally bought the truck in 1999 and it had no motor. They added a 7.3 IDI to it, and used it for a number of years, until it broke down and sat. The engine was "rebuilt" and then sat for a few more years. Then this guy started driving it around as a welding truck, said it ran great and took him about 40 thousand miles. Then, it started overheating. He had some hole in the wall mechanic work on it, he just replaced the thermostat. Then, a new problem arose. It would start loosing coolant. Coolant in the tailpipe, little in the oil. I figured it was either head gasket or cavitation, most likely the latter. However, as I pressed him for more details, he claimed that the motor rebuild was a 6.9 block they had put 7.3 heads on. I've searched and searched on google, and found one person who claimed that they did this, and a hundred others that said it couldnt be done. If it is in fact a 6.9 block, that would rule cavitation out, correct? I havent done any of the tests, I want to know what I am dealing with before I start. So anyway, to the gist of my post here. How would I go about determining if it is, in fact, a 6.9 block with 7.3 heads? If I can fix this truck up rather cheaply, that would be a much better alternative to idling my 97 7.3 all day at the ranch. Thanks, and sorry for the long winded post!
To add to this, the starter,or solenoid is out in some capacity. Try to start and it just clicks, all power goes out. Turn off and back on, power comes back.
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