spun bearing

[wilsoncj6]

i think i spun a bearing in my amc 304. anyone else ever do this? what kind of sound did it make? how did you fix it? can i fix it from underneath by taking off the oil pan? i really don't want to pull the engine! thanks for the help!!!

[Sgt. Dave]

If you spun a bearing, it's overhaul time! Turn the crank( or replace)\ align hone the saddles..

I'd start thinking "remanufactured engine"

[Thomas DeBusk]

I thought the 304 was just like the 360, and I did the bearings in my 360 without pulling the motor.

The trick is getting the bearings out without pulling the crank. Loosen the caps slightly. Get a cotter pin slightly thinner than the bearing. Splay the ends into a "t" with the loop at the bottom. Turn the crank until you see the oil hole, then poke the loop into the oil hole so it's caught by the splayed crossbar.

Now as you turn the crank (in the correct direction) the cotter pin will catch the bearing and force it out. Oil the new one and put it back in the same way. Do one or two bearings at a time so the crank won't move too far.

[joe]

I agree with Sgt Dave. If you spun a bearing you "will" need to pull the crank and at least have that one journal re-surfaced so you may as well go through the whole thing while you're in there.

[Rogue]

yea pull the engine, it sucks but don't forget the bearing spun for a reason ( prolly oiling prob ) hot tank block, cam bearings, resize rods, turn crank, align hone block i'm currently in this process expensive but i know what i got rather than depending on a rebuilt unit cuz as far as i'm concerned a warranty don't mean s**t if you got to pull the thing back out

[Rogue]

hey i just realized you're from PC, rite down the road from me if ya need a hand give me a holler

[wilsoncj6]

thanks guys! i'm going to go look at a couple of used 360s today, and i'll go from there. i might change the bearing like thomas did, just to last until i can do a full rebuild. and rogue, i just might be giving you a holler! thanks!

[OBX-AUTOMOTIVE]

YOU SAID..JUST TO LAST???........ ..YOU GOT THAT RIGHT!!!HOW ABOUT BEFORE IT WARMS UP...............................RAP,RAP,RAP,.. ..WHY WASTE YOUR TIME???.....SPUN!!!!!!!!!!!..WHAT ABOUT THE ROD...HELLO!!!! :confused: :confused:

[wilsoncj6]

<blockquote>quote:</font><hr>Originally posted by GEMOBX/77/401:
YOU SAID..JUST TO LAST???........ ..YOU GOT THAT RIGHT!!!HOW ABOUT BEFORE IT WARMS UP...............................RAP,RAP,RAP,.. ..WHY WASTE YOUR TIME???.....SPUN!!!!!!!!!!!..WHAT ABOUT THE ROD...HELLO!!!! :confused: :confused: <hr></blockquote>

huhh? am i missing something? what about warming up and the rod? i was led to believe than a spun bearing is just that. i didn't think the rod itself was effected. please explain if i'm wrong! which i might be! thanks!

[joe]

The rod should be checked in case it went oblong or slightly twisted at the big end...a spun bearing creates a lot of heat.
I know that one guy above said he just put new bearings in but he didn't say he "spun one". I've never yet seen a spun bearing that didn't score or gall(sp?) the crank journal and didn't need re-grinding.
Unless that crank journal is baby butt smooth and shiney a new bearing won't last at all. Not only have you wasted time and money you may not get so lucky next time as to just spin the new bearing but may poke a rod through the side of the block :(

[wilsoncj6]

i see now, thanks joe! thanks everyone for all your help! i just talked to autozone and a rebuilt 360 is only $1049, so i'm going to go for it! i love my jeep (of course) so i want to do this so it will last! she's a '72, so i'm going to have a lot of fun with the bolts! yikes! thanks again!

brett

[joe]

Brett, since you're going from a 304 to a 360 make sure you buy the "long block" which includes heads cause the 304 heads won't work on a 360. The 304 intake and exh manifolds will though.

[joe]

Brett, as an after thought here you may also have to get a 360 flywheel and crank balancer/dampner but I'm not 100% positive on that but it's worth checking into before you order the 360. Maybe someone else here can add to or deny this?

[Crazy_Jeepman]

Yes, a Harmonic Balancer and Flexplate/Flywheel will be needed for the 360. I have good Harmonic Balancers. Flexplates should be replaced new. I have yet to see a crank survive a spun bearing, this is caused by oil starvation and this causes damage to the crank, by the bearing adhering to the crank and spinning in the rod or main journal. Wearing material away from the crank, and the rod or main journal as well as the bearing. Putting a new bearing in a motor that has actually SPUN a bearing is pointless unless crank is pulled and reground. If a rod bearing is what spun then the rods must be checked so as the proper inside diameter and roundness can be checked, if a main spins then the block would need to be checked. Going to a rebuilt 360 is the best idea. Good Luck ;)