What exactly happened? (rod bearings)

[Aproductions]

So I just tore apart my 96 rs and this is what I found. (It was knocking by the way)

They are in order 1-4

2 looks like it wore in the middle

4 is all chewed up and a different color then the rest. The top right corner got chewed off too. (see pic)

 

[danielbo91]

What's this car rebuild before or no if not maybe bad assembly when assembled, or two oil contamination, three low on oil possible, bad oil pump have you check your oil pump yet I suggest you inspect the oil pump. But was the motor rebuild before, or no and this a 420a engine right.

 

[Aproductions]

No I have not checked the pump yet. I bought it like 2 months ago and it was burning oil like crazy.

 

[danielbo91]

I suggest that you check the oil pump, it could have bad vale stem seals that it was smoking, or two it may have bad piston rings how many miles on this car, but it looks it was oil starved one point of its life.

 

[#40Fan]

Probably ran low on oil a few too many times. Then a quick right turn will pull what oil is left away from the oil pick-up. #4 being the furthest from the oil pump will get the least amount of oil when this happens.

 

[Aproductions]

so what now? Do I need the crank machined? Also if I don't run low on oil, do the right turns still effect me that much? the baffles for the pan are expensive.

 

[jayson427]

there is alot of things that can vary. if your doing a rebuild i would suggest taking the crank and whatever else your worried about to a machine shop to be check out and measured to spec. you might need bigger bearing or might not but the machine shop can tell you that and it doesnt cost all that much to find out. when i built my motor i went over .10 on my main and rod bearings for a good fit and it gave me great piece of mind knowing it was done right. if your doing a stock rebuild i would take the pistons rods crank and block down so they can check it with a micrometer. as far as the right turns just dont haul ass around corners and keep your oil levels up. if you have the money get a new oil and water pump. it costed me 300-400 bucks to size my pistons, bore the block, shave the crank, weigh the rods to the pistons, hot tank the block and mangaflux it.

 

[bullettdsm]

Probably ran low on oil a few too many times. Then a quick right turn will pull what oil is left away from the oil pick-up. #4 being the furthest from the oil pump will get the least amount of oil when this happens.

^This

Typically the first rod bearing to go on our engines would be the #4. I would say that #2 probably had some debris come in from the crank hole entry (if you look at your crank you will see where the oil comes in from the crank, matches the score mark on the bearing).

Crank needs to be checked out by a machinist to see wether or not it needs to be cut. As well as the rod on #4 should be checked.

MB

 

[Aproductions]

Thanks guys.

Another thing I noticed was the rods were kinda messed up. The caps weren't even like some material transferred on to the other part of the rod. When I took the caps off, the surfaces weren't flat. Hard to explain I guess.