[53fordguy]

Originally Posted by cobalt327

This what you mean?

got any more thats pretty well what i need just need to see the top and maybe a measurement? but thats a pretty good idea!

[53fordguy]

So i got the install done and everything was good, but then uh oh! im not sure as of yet what happened but i think my block grenaded! i poured coolant in and it pours out the oil pan and cyl 4/6! cyl 6 was full of coolant, and something mangled cyl 4 my spark plug was smashed into little pieces and crushed in the bore. i used a boroscope to check but it didn't give me and conclusive idea. any ideas?

After install it ran and idled fine, warmed up and went for a drive, ran thru rpm range 700-4500 seemed ok lots of power!, and i made it about a block then i backed up and it stalled, started it up and coolant was blowing out my tail pipes, so i went home and filled up and tried to fire up and it hydro locked, drained crank case filled 3 ice cream pails full of coolant before i saw oil. drained all cylinders, 1-7 OK, 2 and 8 OK(dry). anyone seen this happen?

The guy i got this engine from said the heads have been port/polished, its a 3970010 block .030 over. will post pics later.

[cobalt327]

I'm not following what you mean: "1-7 OK, 2 and 8 OK(dry)." Are you saying those 4 holes are dry and the others are wet?

The block could have frozen and cracked. They sometimes won't leak again until the block is heated up, then the cracks open up and water goes everywhere.

The smashed plug indicated mechanical mayhem in that cylinder. Most likely the rod has failed and the piston then was able to contact the plug. Or it dropped a valve and that beat up the plug. Either way, it's terminal, I doubt you had such bad detonation that the plug would look like that- although detonation CAN crack the porcelain, and overheating/detonation can ruin the ground strap.

If there was a rod that let go, it can cause the cylinder to split. Overheating can warp the decks and cause the head gasket(s) to lose seal. Either case will let water into the cylinder.

But this is all guessing, not knowing which holes are wet, etc.. But it does not sound good- that's for sure!

[53fordguy]

yeah 123 5 78 are all dry and ok, number 6 was wet and leaking coolant, 4 was too with the smashed plug, i dont know it its a rod cause i can still start it and it still has compression in those holes, i looks like somthing inside 4 let go and mangled the inside, i wont know till i pull the head but its definitly terminal as i also pulled a valve cover and nothing is coming up the pushrods( after filling with new oil). i could see around the piston edges and they looked ok,, im not thinking valve as all the rockers move in an ok manner, i would assume if i dropped a valve it would have bent and held the valve or the the spring would be cocked.

[cobalt327]

Might be a nut or hard piece of whatever got into that hole and wiped out the plug if a rod or valve didn't let go. That wouldn't explain no oiling, though. I'm a bit surprised it will still start up and run. I wouldn't run it anymore, until you find out what's going on.

Maybe a piece of the piston above the compression ring broke off and took out the plug, etc.. That's been known to happen if there's a lot of detonation.

Good luck.

[53fordguy]

thanks! yeah i just wanted to see if she was sucking coolant still and if i made a hole in the piston, im going to tear into her this weekend and hope i can find another donor motor before my last year of school for my apprenticeship wooot!

[53fordguy]

so ive ripped it apart, not sure what happened but something was in the cyl 4, and a nice hole in the block.still havent figured out how it happened wheather someine left it in the engine when i bought it.it appeared to be a helicoil/or a valve seal, but i noticed no marring or stress on the valvetrain, all valves opened and closed properly. what a waste of a 3970010!

also in using thew factory cam in this 350, too much cam for crossfire? i was about 6-7 dergrees advance, cleaned throttle body, fresh fuel used the 82 distributor, and no other mods. ive bought another 4 bolt 350 and im wondering if that may have been part of the problem. still no idea what started the leak to hydro the block,

pics to come, nothing but a mangled .020 piston and a big t shaped crack in the cyl wall, no major evidence of a lifted head gasket or a intake leak,