Main bearing failure

[williamsGN]

Last year I had a headgasket let go, so I decided to replace all the bearings too. Got direct replacements from PAW - MS960PSTD, the same number as the old bearings. Only difference being a 'B-1" stamped below the clevite 77 on the other end. Used assembly lube and torqued the ARP studs to 90 ft/lbs in segments with moly lube. Set the thrust according to the service manual. Made sure to replace all the caps properly in order. Ran fine for 1800 miles. Just had the trans and TC rebuilt and when I started to drive the car I heard rumbling from the engine area, thought it was the trans. But pulled the pan and the #2 and thrust bearing and they are all the way down to the copper completely. Had good oil pressure till the last time I drove it and noticed pulling in that the oil had dropped to 1 psi on the autometer, though the dash oil light never came on. Only put 80 miles on the car since the trans and didn't notice any oil pressure issues till the last time I pulled it in the garage. Trying to figure out what went wrong.

 

[wickedtt]

What converter did you use? what was the clearence from the flywheel to the converterbefore bolting it up?

 

[williamsGN]

My Art Carr 9.5 I just had rebuilt along with my trans. Pushed it in all the way on the trans, bolted it up to the engine and had maybe and inch between the TC and flexplate before pulling it together and bolting in.

 

[BlownV6]

My Art Carr 9.5 I just had rebuilt along with my trans. Pushed it in all the way on the trans, bolted it up to the engine and had maybe and inch between the TC and flexplate before pulling it together and bolting in.

What part of an inch??? Mike

 

[williamsGN]

Like I said, maybe an inch between the TC and flexplate, what part is unclear ?

 

[BlownV6]

Like I said, maybe an inch between the TC and flexplate, what part is unclear ?

Trust me Im no expert on your type of trans , heck I wouldnt even know what it looked like if you gave me 3 to choose from!! But in every other type of trans that I do know about the converter has a slot cut in the tube that slides into the trans. That slot engages into the front pump!! Normally that engagement is say 1/2" , so if the converter was all the way back the 1" your claiming I would think it would have disengauged from turning the pump. Since you drove it 1800 miles I would have to assume that the trans worked but 1" clearance from flexplate to face of the bolt tabs on converter just sounds impossible!! Mike

 

[turbobitt]

What transmission are you using ?
Allan G.

 

[boostingbuick]

A couple of things come to mind. The bearing clearance was too tight. The oil passages was not clean. And one I have just seen recently, a cracked crank. Not broken, just cracked. Ours was the number three main and caused this issue twice. The machine shop missed it. Hope this helps.

 

[williamsGN]

what transmission are you using ?
Allan g.

200r4

 

[bison]

Line bore issue or crank problem most like likely.

 

[HIboostGN]

It is weird it happen 1800 miles after the head gaskets but RIGHT AFTER you picked up the car after the trans and convertor install! I think whoever rebuilt the trans might have messed up on the pump and that is expanding or the converter is ballooning and caused the thrust to go?? If the block had problems before it would have showed up on the first set of bearings NO? Unless you broke or cracked the crank before you had the tranny work done and then it finally let go after the tranny work?

 

[TurboBuRick]

Does seem fishy this came about after the trans was r&r'd. Blownv6 make a good point. An inch of tolerance between the converter and the flywheel is excessive. Pretty sure you only want to have something like 5/16 w a 200-4r. Should have used washers to take up the space. That way the converter is sure to stay engaged in the pump. Any hard pulls on the new trans?

Did you unbolt the converter from the flywheel and see if it still have that play?

Do both sides of the thrust bearing show wear?

Did you prime the oil pump after the last set of bearings went in?

 

[The_Six]

Did you put the Trans in? I had this happen to me one time with a truck but the Trans shop admitted the messed up when they put the trans in they only had put one bolt in connecting it to the engine they fond it when test driving the truck started doing some crazy stuff evidently and then shortly after I had a rod knock come to find out the engine and trans flexing had broke the crankshaft. I new some one that worked at the trans shop otherwise I may not have known it happened.

 

[williamsGN]

I put the trans back in, everything was connected properly and double checked. Even took it to a local trans shop to verify my work. They found nothing wrong with the trans installation. "An inch" was a generality, I didn't measure the precise distance between the TC and flexplate before re installation. The TC seemed to engage on the input shaft properly and I don't believe it moved far enough forward to disengage the pump. This was a rebuild on the existing trans and TC. No hard pulls on the trans after rebuild and I disconnected the ecm and cranked the engine a few seconds after installing the bearings before firing it up. Both sides of the thrust bearing are shot.

 

[TurboBuRick]

I disconnected the ecm and cranked the engine a few seconds after installing the bearings before firing it up.

Wait a minute, stop the presses. This is how you primed the oil pump?

 

[bison]

Wait a minute, stop the presses. This is how you primed the oil pump?

 

[pajo]

prime

have you ever heard of priming the engine ..now you will ..

 

[williamsGN]

Everything had assembly lube on it and pressure came up on the gauge within seconds of cranking. I don't think 3 seconds of cranking destroyed the bearings. Especially since they last 1800 miles, and I should mention again this was not a full rebuild, redid HGs and dropped the pan and changed the bearings. As far the bearings, this wasn't much more than an oil change and I don't think ppl reprime every time they change their oil.

 

[forcedfedv6]

Hey J, you should take a picture of the bearing and post it to get better answer to what you are asking, as far as the prime goes, you only need to prime the motor and pump if you take the pump out completely and there is no oil in it whatsoever you did nothing wrong by cranking the car for a few seconds to get the oil pressure up before firing up the car and trust me that didnt destroy the bearing at all, those bearing were not the H type of bearing, and with the knock you were experiencing I would say that was what probably did the bearings in, most rebuilders usually pack the pump gears with Vaseline or grease to get the oil up to the pump before firing the car and prevent it from capitation, also I would admit that 1" of space between the flywheel and TQ is a little excessive, it souldnt be more than 1/8th of an inch of play between the two..

hope this helps.

 

[williamsGN]

Thanks for the reassurance on the prime, but the false knock from the tranny going wouldn't ruin the bearings as far as I know.