Engine Bearing Questions

[Vsho93]

So far my car will not turn on, seems as if the engine is locked up for about a month now. Today I take the serpentine off on my 3.2 to verify my other pulleys I decide to crank the engine while the belt is off and it turns on for around a second and a half, shreeks and shuts off again. I'm obviously thinking I spun a bearing but could I be wrong?, why haven't I completely seized the motor?, lastly why does it turn on?.... I know without pulling the oil pan and ect... I won't know for sure but I'm wondering if it's even worth it?

 

[1993MTXSHO]

if it turned over and then made a horrible sound like that, odds are you spun the bearing, so either put a new crank and set of bearings in or just replace the engine. Course if you replace the crank and bearings make sure to check everything else and makes sure its ok, no metal anywhere etc.

 

[HotRodKid]

why haven't I completely seized the motor?

because its very hard to ACTUALLY sieze an engine. i did it ONCE, but once teh car sat overnight and totaly cooled off i was able to start it again, and it drove for 14000 more miles ..... im pretty sure i seized my pistons to the bores, because the compression went to garbage waaaay faster then the rod bearings did

you can overheat a car and get it to sieze, but in all reality its just 2 parts that have a very very bad weld between them

once things totaly cool off again its not hard for stuff to break free again, even on its own, things contract to where they belong again and the weakest link (the weld) breaks

 

[Vsho93]

sweet, answered my questions.... guess I'm installing new crank and bearings

 

['94SHO]

Wait..

The crank is forged.. At least have it checked befoere you trash it...

 

[HotRodKid]

check the crank first, ive seen plenty of people spin bearings and still have a perfectly usable crank. if the damage is purely visual (ie: you cant catch a fingernail on the damage when scratching at it) it can be repolished by hand

if the crank is trashed, swap it out and give all the old stuff to someone who wants a basic engine for rebuilding

 

[AREA 91]

I have heard a massive rod knock that was cured with only new bearings. It just depends on the damage.