in the last 5 days i blew up 2 mint motors. Running my sohc turbo setup on 8 psi on a nice tune, barly beat the crap out of them also. I had bought a clutch and fly from LSD motorsports. When i blew my Y8 on wed i took it all apart and all the main bearings were all chipped and the copper was showing on all of them. So i picked up a mint 60k Y7 that night and dropped it in on thursday night, finished it up on friday. I swaped that motor with my lsd motorsports clutch and fly that i had on my Y8. Last night i was crusing my car and my oil light started to come on at idle and my car is knocking above 3k rpm. One of my buddys said he thinks my flywheel is unbalanced which is causing my bearings to fry. Any input on this or has anyone ran into this problem? thanks

TK

 

do you have an aftermarket pulley setup on there?

 

nope. OEM, never touched it.

 

sounds like the flywheel could be out of balance if it's chewing up the main bearings....

 

keep a stock flywheel on the next.

 

you guys think the clutch would be out of balance also?? i was on their site and the flywheel was only 150 but the clutch was like 300.

 

It must be seriously out of balance to destroy the mains in that short of time.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sohc_turd &raquo;</TD></TR><TR><TD CLASS="quote">It must be seriously out of balance to destroy the mains in that short of time.</TD></TR></TABLE>

yea this is the only thing we could think of that is detroying my motors. both motors were mint and i used the clutch and flywheel on both. Its the only thing that makes sense. i am chatting with the company right now on aim to see what they can do for me

 

Not that it really makes a difference, but i also run the LSD d series flywheel/clutch combo. Mine seems to be working like its supposed to.

Also in the past, ive taken flywheels to the machine shop to have shaved, which i never re-balanced with no hint of ill effects upon tear down.

but who knows... anything is possible.

why not take some pics of the bearings and post them.

You sure its not detonation killing them?

 

2nd for pics of main bearings pistons plugs and cyl walls....

 

heres one of my rod bearings that was completely fucked



i will go snap pics of all the main bearings and pistons/cyl walls.

 

you should (if you have the money and want to) take it to a machine shop and have them balance it and see if its out of balance. If it is then I would talk to the company and see what they can do..... it should only cost about 50 or so but couldnt say 100%

 

yea i am talking to the company right now. they take forever to respond.

here are the pics

Pistons were in oil soo they are dirty in this pic




walls look great

 

I don't know much about D series, but aren't the bearings with the valley in them supposed to go on the block side?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Shmaa &raquo;</TD></TR><TR><TD CLASS="quote">I don't know much about D series, but aren't the bearings with the valley in them supposed to go on the block side?</TD></TR></TABLE>

just like on any motor there are bearings on both sides set on the block and a set on the main caps.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TallKyle &raquo;</TD></TR><TR><TD CLASS="quote">

just like on any motor there are bearings on both sides set on the block and a set on the main caps.</TD></TR></TABLE>

I think what he is saying is that the valley and hole provide oil flow. And that the opposing bearing would just be flat (or have no hole at least). If the oil passages were above the crank (in the block) and there was no oil passages below the crank (the caps), then there would be no way for the oil to get in between the bearings and crank.

Is that what your saying Shmaa?

But if he had two motors that he didn't open before using, then the chances of both having bearing improperly installed would be pretty slim.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Westrock2000 &raquo;</TD></TR><TR><TD CLASS="quote">

I think what he is saying is that the valley and hole provide oil flow. And that the opposing bearing would just be flat (or have no hole at least). If the oil passages were above the crank (in the block) and there was no oil passages below the crank (the caps), then there would be no way for the oil to get in between the bearings and crank.

Is that what your saying Shmaa?</TD></TR></TABLE>

Thats what I thought he was saying also, are they OEM bearings ?

 

o i read his question too fast. Well this motor was never touched and it was all OEM. soo i think there is valleys on each bearings. i think they are all the same

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Westrock2000 &raquo;</TD></TR><TR><TD CLASS="quote">

I think what he is saying is that the valley and hole provide oil flow. And that the opposing bearing would just be flat (or have no hole at least). If the oil passages were above the crank (in the block) and there was no oil passages below the crank (the caps), then there would be no way for the oil to get in between the bearings and crank.

Is that what your saying Shmaa?

But if he had two motors that he didn't open before using, then the chances of both having bearing improperly installed would be pretty slim.</TD></TR></TABLE>

Thats right

Did you take the motor apart yourself? have you messed with the main bearings meaning move them around after it was pulled apart? on a b-series there are 5 with valleys and 5 flat ones.

 

crank is still in the car. never touched or looked at the bearings under it. i just pulled off the gridle and was shocked with what i seen.

 

bump for tk! i would also like to know about this y bearing issue

 

I've never seen a flywheel destroy a motor. I'd say poor tuning caused both to spin bearings.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostedej1 &raquo;</TD></TR><TR><TD CLASS="quote">I've never seen a flywheel destroy a motor. I'd say poor tuning caused both to spin bearings.</TD></TR></TABLE>

A bad tune does not cause crank woble/walk which is what destroys bearings like that. I have never seen a motor that will spin all the bearings in the motor the only thing that I have seen damage motors like that is a flywheel/clutch out of ballance.... I have seen crank pulleys bent/out of ballance cause a slight crank walk which will cause this over a period of time if it doesnt blow you oil pump first

 

so you guys recommend balancing the crank pulley too?

 

depends.. Something like his motor I wouldnt because its stock and more than likely hasnt been taken apart, But the aftermarket flywheel and clutch combo I do... Have everything balanced when I build a motor. But thats just me. I like to make sure everything everything in the rotating assmbly is balanced so things like this dont happen