wear on main bearings due to no balance shafts

[shad0w2.s_tur80]

i have a 89 2.5 block without balance shafts

i was taking the main caps off to replace the bearings and i noticed that cap #3 had the grove in the center of the bearing worn away completly. but the bottom bearing didnt look bad to me the grove was stil intac. i know the balance shafts where removed and the engine was ran for 30,000 miles then dissasmbled.
could the wear be caused buy runing a 2.5 at higer rpms with no shafts ?


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[Turbo224]

I think it is possible that its just wear from high rpms. I could be totaly off here, but wouldn't the most wear occur on the cap side of the bearing since the that is the bottom of the stroke? Maybe that doesn't make a difference...

[4 l-bodies]

What brand bearings are they? Reason I ask is for our motors Clevite 77 use a 360 degree groove on their bearings. Federal Mogul main bearings are only grooved on the one side. Is this what you are seeing?
Just make sure that you have the balance shaft oil feed plugged, so you aren't starving the main bearings due to hemorrhaging oil out of potentially open balance shaft hole. There are literally hundreds of 2.2's & 2.5's running out without balance shafts and have no oiling issues.
Todd

[shad0w2.s_tur80]

What brand bearings are they? Reason I ask is for our motors Clevite 77 use a 360 degree groove on their bearings. Federal Mogul main bearings are only grooved on the one side. Is this what you are seeing?
Just make sure that you have the balance shaft oil feed plugged, so you aren't starving the main bearings due to hemorrhaging oil out of potentially open balance shaft hole. There are literally hundreds of 2.2's & 2.5's running out without balance shafts and have no oiling issues.
Todd

that kinda odd how all the bearings have the groves all the way around but the center one. but everythig is fine i geuss i am just realy nervus or just have no faith in this car everworking again after sitting for so long.

[Ondonti]

Im guessing you didnt measure to see if the bearing was actually worn.

Im going to guess your main bearings are not all from a matching set.

clevite 77's for my motor are maybe 220 degrees of oil groove ( the rest of the middle of the bottom bearing is flat).

It also looks like when you say "bottom bearing" you really mean top bearing.

Clear up what are you saying.

[shad0w2.s_tur80]

Im guessing you didnt measure to see if the bearing was actually worn.

Im going to guess your main bearings are not all from a matching set.

clevite 77's for my motor are maybe 220 degrees of oil groove ( the rest of the middle of the bottom bearing is flat).

It also looks like when you say "bottom bearing" you really mean top bearing.

Clear up what are you saying.

i didn't measure because i didn't see a grove in it (thought it was totaly fubared) and my crank is at the machine shop.

the thing that puzzled me the most is all the bearings are the same i looked at the numbers on all of then and they matched al 6

the clivite 77s i just got from fwd are 360* of grove on all bearings that kinda lead me to belive the bearings should have a 360* grove on all of them

yes your right ... i have the engine was upside down

my biggest concern was not the bearing being bad (seeing as i am replacing all of them regardless ) it was what caused it to go bad. i wanted to make sure that it wasn't because the engine had the blanace shafts removed. i do not want a repete failuer

[turbovanman²]

Looks to me like normal wear and tear and also a piece of debris got thru and scored the one bearing but due to the 180 valley in one bearing, its fine. No BS's won't cause that.

[Directconnection]

that kinda odd how all the bearings have the groves all the way around but the center one. but everythig is fine i geuss i am just realy nervus or just have no faith in this car everworking again after sitting for so long.

If it wore to the point where the groove wore away, you'd see copper. Also, hard to believe the bottm side would be worn down .020 or so to wear the groove away, yet the top bearing is perfect. You'd have almost no oil pressure also...

Like Todd said, some bearings are full groove and some are half.