Ferdy Mint
Full Access Member
We spent about 6 months locating a suitable donor truck to replace the motor and tranny in our 89 F250 7.3 with a C6. It has coolant in the combustion chamber, probably offset core and PO didn't use ELC or additive. We found a 93 F350 with 200k on it and a ZF5. It had not run in 18 years, after the PO died. The motor turned over with a wrench so we bought it and pulled it onto our car hauler. Also got a cool flatbed. So it was a good deal for $900. We used a lot of parts so far. Even the cab will get cut up to replace the right side of a 97 F350 that my son wiped against a tree, doh.
We ran the motor for about 2 minutes - no coolant - before starting to swap it over, it sounded OK. It fired up after pulling the truck for about 100 feet.
After getting the tranny rebuilt and installing it and motor in the 89, we now have a ZF5, 3G alternator and serpentine belt. Woo hoo. I sold the C6 for $700. But it also has a tap once she's warmed up. It's not a rod knock because it's only there on accell and idle. On overrun you don't hear it like a rod knock would. It sounds like it could be piston slap or crack, but she's not smoking and power is good. There's no skip but idle is slightly rough. Hard to tell, all our IDIs are a little rough at idle.
Question for the forum is can a bad injector cause a tap that would fool an old gasser guy like me into thinking it's mechanical? I'm planning to swap in some rebuilt injectors from Classic Diesel or Accurate Diesel.
We ran the motor for about 2 minutes - no coolant - before starting to swap it over, it sounded OK. It fired up after pulling the truck for about 100 feet.
After getting the tranny rebuilt and installing it and motor in the 89, we now have a ZF5, 3G alternator and serpentine belt. Woo hoo. I sold the C6 for $700. But it also has a tap once she's warmed up. It's not a rod knock because it's only there on accell and idle. On overrun you don't hear it like a rod knock would. It sounds like it could be piston slap or crack, but she's not smoking and power is good. There's no skip but idle is slightly rough. Hard to tell, all our IDIs are a little rough at idle.
Question for the forum is can a bad injector cause a tap that would fool an old gasser guy like me into thinking it's mechanical? I'm planning to swap in some rebuilt injectors from Classic Diesel or Accurate Diesel.
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