Thread: why do i keep spinning rod bearings?

I dont seem to knoe why i keep spinning rod bearings. The first motor wss an l36 topswap,l with xp csm and 3.4 pulley with 160k on the motor. After i got it tuned and did a run the bearing spun. Very little kr. Second motor as an l67 . Samebuild. Had i also spun a rod bearing after s performance run. Oil was changed after i let it idle for about 10 min. No water in oil our any thing. Idk whts going on lol but i think im gonna rebuild thd bootom end of the l67.


Srry for spelling, doing this from lol

Odds are you got a bad second engine, thats the bad thing about buying used engines you never know how the previous owner treated it, how long they waited to replace the lim gaskets after they went and so on.

You have to be kidding me!!! I hate to read this!!! Sorry man..

I'm a little confused on the whole "did a performance run" thing. Want to elaborate?

With wording like that, the issue might be your right foot.

Originally Posted by BillBoost37

I'm a little confused on the whole "did a performance run" thing. Want to elaborate?

With wording like that, the issue might be your right foot.

It was 0-100 on a back country road. It wasnt even d wot though thats wht i do+nnt. It was prob like just over 1/2 bc its a stock trans

Both motors spun bearings after similar runs. Could it be boost related. I noticed my gauge showing full boost at very early throttle ( not even half throttle)

I'd spec the bearing contact on the cam. IF for some reason it is off you oil pressure could be low and staving the mains. Also if you are using a cookie wheel for cleaning the gasket surfaces that could be your other problem.

Whay else should i check to diagnose the problem?

I doubt its anything tune related if you wernt kring like a mofo both times. Iv got 162k on mine and it is running a 3.2 pully on a genv blower..... Im about the farthest thing from nice to it as well.

Yay me! Just spun rhe bearings in the NA motor i just put in like 2 days ago. Is my luxk seriously that bad lmao

I would switch platforms

Are you buying used blocks or rebuilding these? I was under the impression that after rebuilds there was some sort of break in period " being nice to it " ... I babied mine for 2000 miles then 2nd oil change at 2k. I can run this car no problem I'm 9k deep. Long story short are you dropping this thing in and beating it shortly after? New oil pump? Good luck either way.

I dont get it lol i wasnt beating it and yes it was a used motor 130k. Im thinking maybe call it quits lol. Especially after doing it to a stock na motor.

Dude your in the same spot I was about 6 months ago four motors within two months period . It's not fun

I swapped to a 27K L26 to put my cam and top swap on. I've babied it to a point, but after these threads of nightmares I got it on the highway yesterday and opened her up... Hit OD at 110, I let off several seconds after I burried the needle but it was still pulling like a beast. Took the boys out for ice cream later yesterday evening in it.. LOL..

With high mileage, there are no guarantee's with what you'll get. I mean that motor ran for YEARS with a consistant setup or maybe it was wound up so many times Ray Charles could see it was ragged out before it was pulled and you purchased it. There's no telling. But after it sat, you picked it up, threw new to it parts on it and dropped the hammer so to speak... Also, if anything was broken loose on the top end (intake, heads, ect) possibly coolant ran down to the crank, got in the bearings, soaked in some, then ended up in the oil. That means that bearing is hosed. IMO, once bearings see coolant, it's a matter of time before they spin. I've had two motors (3100's one mine one my grandfathers in his lumina) that blew intake gaskets. My olds lasted a year, the Lumina is still running, but knocks at higher RPM's so it's will go eventually. coolant washes the bearings of the oil and it's hard to get oil to stay where it needs to afterwards...

But anyway, I rambled.... Again, I hate to hear this bro and wish circumstances are different. If you leave the platform, you better keep your azz on the forum.. LOL