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+--- Thread: Blown Motor. (/thread-2936.html)
Blown Motor. - NateMob - 10-21-2011
chuzie Wrote:DUDE! WOW! That is no joke there. My .02 are something was either left in there during the build, was sucked in through the intake, or fell apart in the intake/carb that made its way into the cylinder, jammed between the piston and the valve and caused catastrophic failure at TDC. My basis is the picture of the carb debris. What is that stuff? Where in the carb did you find it?
yeah there is an entire piston in the oil pan. :rubeyes:
That debris was actually directly underneath the carb in the intake. Those chunks of metal were sitting right there when i pulled the carb off the intake. I couldnt get the heads off but i slid my fingers into the #2 from underneath and feels like it punched/cracked the cylinder wall. Should be another good picture.
Nate
Blown Motor. - broncosbybart - 10-21-2011
Nah, if something was in there during the build, it wouldn't have made it to 5k. If it is running too lean (intake leak), you can burn pistons up. What color were the other plugs? Your push rod bent because the valve contacted the piston at TDC, as it came apart. Chances are good that the head is cracked now as well.
You ain't gonna buff that one out... That sucks.
28 oz engines were made up until about 79' to be safe. maybe 84, but 79 and earlier will be a definite. might take crawdad up on his offer.
Blown Motor. - chuzie - 10-21-2011
Missed the 5K part. Disregard.
Blown Motor. - Timstrk - 10-21-2011
The metal below the carb is former piston. Once it let go it shot metal all through the engine. It is a result of the failure not the cause of it. Check the valves and see if the guides are worn. Or if any of the valves are broken off. No space for anything that big in the combustion chamber. A greater than .500 lift cam without clearancing the piston will cause contact issues. I had a valve guide go bad and allow the valve to tip sideways just enough to contact the piston and grenade. The bent pushrod is interesting. I did that to a friends 383 Dodge one time. At 7200 rpm though. 12 sec 1/4 mile car at 3700lbs.
Tim
Blown Motor. - firefighter2134 - 10-21-2011
That sux dude. Good luck finding a donor. I had a guy call me other day about a 302 cheap lemme c if he still has it
Blown Motor. - broncomatt - 10-21-2011
Man that sucks! Sorry to hear that. I reminds me of the cash for clunkers program, we did that on purpose. What happend to yours is anyones guess. I would say something was left loose, not much worth saving. I can check our local yard for a block if you need one.
Blown Motor. - blazinchuck - 10-22-2011
nate...a local bronco guy here just pulled a 302 out for a new crate motor, he said i could have it...but you are welcome to get it. its here on johns island. dont know anything bout it yet. ill check tomorrow if you havent found anything yet. very sorry to hear this man...wish i was closer to help ya
Blown Motor. - bucketobolts - 10-23-2011
I'd place my bet on a valve spring.
What are the specs on the cam?
Improper balance would have knocked the bearings out long before now.
Blown Motor. - Crawdad - 10-28-2011
Nate,
You still planning to come up here on Sunday still?
Blown Motor. - NateMob - 10-29-2011
Yes sir, gonna head that way after church if that's cool with you. Get up there about 3ish...