How does that happen, it appears to me that the piston hits on the crank throws. The engine would turn over until it hits the crank throws then bam nothin. Could it be bearings, is their any way to fix this. Thanks for any help.

 

Hits the throws or the counterweights? Sounds like your crank is designed for use with a longer rod. A machine shop might be able to get you enough clearance and rebalance, or you might need to change parts.

 

Engine is completely stock, probably never taken apart. Ran great for a long while, i'm stumped no idea how it happened. As i said in a previous thread it ran great til one day it just locked up when i was cranking it.

 

If it's never been taken apart then it should be to see what kind of damage was done to cause the problem.

The piston can never hit the throws. The con rods hold it away. They can hit the counterweights on the other side of the crank when the throws are on the opposite side of the crank. Even if a wrist pin bearing was completely gone, I doubt there's enough space to let the piston hit the counterweigths. It sounds like there's going to be extensive damage in the engine.

Engines don't just lock up like that without major damage.

 

This is the same engine that had rust in the cylinder? It sounds like it has some serious problems. You'll need to tear it all down to see what's really going on. There probably won't be any easy fixes in any case.

 

You may be looking at a shortened (bent) rod, or bent wrist pin, or broken piston. Since you're that far, you might as well pull it all the way down and check it out. If you're reassembling it and discovering this, you may have the piston/rod assembled incorrectly.

 

Thanks vadar, that helps a ton . I've already tore the engine down and pulled the piston out of the rusty cylinder.This engine has rust in the same cylinder as that rod, so i'm thinking water got in their hydro-locked and then bent the rod enough to hit the throws. It sat for a while allowing rust to get into that cylinder. Do all 350's have the same rods out of the factory, because i have another one that i could pull the rods out of and install in that engine. Would I have to replace all the rods or just the one? And thanks again for the help.

 

:bump:

 

All the 350s came with 5.7 rods. If its a stock motor you can swap in one rod but you said that cyl was rusty? Is it going to clean up with a hone or do you have to bore the block? And do you know where the water came from?

 

The rust came from not having an air breather, the rust is smooth and no dimples, so im assuming that it will clean up rather simply. I was just wondering it the rods all weighed the same.Thanks for the advice.

 

I looked at it again and it turns out 2 of the rods were bent hitting the counter-balance. I pulled 2 of them off of another engine and i noticed that they were different. The donor block has an "X" cast into it and the donor rods look beefier. Should i just pull the rest of the rods out of the donor block to match it.

 

X rods are better rods. If you dont mind swaping them all out thats great you will have a beefer rod. Or you can take one bad rod and the two X rods and have them weight matched at your local machine shop.

 

Would machining them make them a whole lot weaker? Otherwise i think I'll just leave the rest of the rods stock, I'm not planning on making much power with this engine until i stroke it, then i'm going all forged.