How In the Heck Would This Happen

icanfixall

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Those threaded holes in the crank flange are drilled thru and the broken bolts should be really easy to back out of the flange. Installing a differant crank in an engine is no easy job. You can't just flip the engine over. Remove the crank and install another.... Unless you have 8 arms to move the rods around... I did this once and only once on a 250 inch chevy 6 cylinder... What a puzzle that was getting all the rods positioned correctly so the crank would settle into the mains...
 

MUDKICKR

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Those threaded holes in the crank flange are drilled thru and the broken bolts should be really easy to back out of the flange. Installing a differant crank in an engine is no easy job. You can't just flip the engine over. Remove the crank and install another.... Unless you have 8 arms to move the rods around... I did this once and only once on a 250 inch chevy 6 cylinder... What a puzzle that was getting all the rods positioned correctly so the crank would settle into the mains...


thats why you take the plugs out and push the pistons til they hit head.
anything can be stripped out if installed wrong, maybe they used the "tighten til it breaks and back it off a 1/4 turn method"
 

Knuckledragger

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Well, if you have all of the pistons pushed to TDC, you really only need four arms. Actually, it isn't very hard to do, but you need to set the crank above the rods for a little while. Once it is in place, you put some stiff, thinwall vinyl tubing looped over the crank from one stud to the other on each rod. Slowly lower the crank down, and the tubing will guide the rods into the correct position (usually, sometimes they need a little help by jiggling them). You can also use straight pieces long enough to lay on the crank rod journals, it will do the same thing, acting as a guide.

If I were in PA, I would take a look at this engine and determine if it really needed a crank, or just a new owner.
 

tjsea

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Bolts are stipped. Engine was in a truck that the guy was doing something transmission wise and had the flex plate off. When he put the flex plate back on he crossthreaded the bolts and tightened them till they pulled threads. The seller didn't do this it was the previous owner (local truck) who then gave up on fixing it.
 

RLDSL

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Bolts are stipped. Engine was in a truck that the guy was doing something transmission wise and had the flex plate off. When he put the flex plate back on he crossthreaded the bolts and tightened them till they pulled threads. The seller didn't do this it was the previous owner (local truck) who then gave up on fixing it.

Which begs the question: how the heck do you crossthread grade 8 bolts into a hardened crankshaft LOL
Some folks have .... er, special skills ;Really
 

justinray

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For 650 he can have it, if it was cheaper, I would buy it, drill and tap the holes the smallest next size up and hope for the best while I started it out of the truck.
 
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