Hey,

So I found out the motor I bought, the middle three journals I guess is what they are called for the main bearings are cracked. The motor was built by abacus racing and I purchased the motor out of a hagard primer coupe un knowingly buying a built motor. It has crower rods and low comp pistons. I heard the guy had zero miles on it, and just beat the shit out of the motor. Think this plays a role in the cracked journals? I was just curious on how to these crack seeing how the look pretty solid..

 

Oil starvation (OHC engines are more susceptable to than a pushrod) due to low levels, beating the shit out of it right after start up, incorrect viscosity oil, lack of assembly lube, screwed oil pump... could be a number of reasons. The crankshafts in are stout, though there is a great deal of force/tension placed on a crankshaft and if the bearings fail, shit will break.

Crankshafts can be welded and repaired, though you're probably likely to find a good crank for less than what this would cost, since a machine shop would have to weld it, grind it, polish it and then balance it to repair the broken one. Though with the middle mains all broken, shit, there is no doubt finding another is the way to go.

Now the slight problem with this is your caps may be screwed as well. So, now you have to do a line bore.

It may just be cheaper to find a bare block, have it bore/honed to the size of the pistons you have (assuming they aren't out of round due to cylinder wall warpage) then use the rods and pistons you have in it.

Got a shitty deal I would say. You bought this out of a vehicle but didnt ask to hear it run first? Dont ever do that. Not sure that is the case, but, sounds like it.

 

It had a slight tick, but went away. He didn't have any coolant lines hooked up so he didn't have it run for long. It sounded decent, but with everyday driving it got worse. I am getting a bare block with a good crank in it, to rebuild with the good internals I have now. I Didn't plan on using this fucked up ass block.


Thanks for your input so far! The crank looks great, its just the journals on the block that are all fucked to hell. The surface that the actual main bearing gets rotated on, wasn't scared,scored or anything, just the back side looked like ass. OH well, atleast now I know I'm going to have a known good motor. I was just curious on what would cause my situation.