IMS failure - how can I confirm my engine is toast?

[Jamesp]

Originally Posted by JFP in PA

Not a matter of being critical, very few engines that have suffered an IMS failure make it with a replacement bearing and not being taken apart and cleaned; the odds against you are very high. You were quite fortunate, literally "one of the few"............

I'd like to see the numbers on that. I did take mine apart and cleaned it with solvents, not ultrasonic. My sense is the stock oil filter does a better job than it is credited with as has been amply demonstrated when they are cut open. What do the chips take out? Seriously, provided the oil filter does not fail, they go through the oil pump and end up in the filter. If they are too big, the end up in the pan. The death blow isn't the chips, its the damage that created them. Now if an open bearing is chosen as an IMSB replacement using unfiltered oil, the story changes.

[flaps10]

There is where I have to disagree James. My main and rod bearings were heavily worn from those chips and my cam journals (they aren't really bearings in any sense) had some light scratches - thankfully light enough that I may have dodged a lightening bolt.

I do agree that the stock filter is better than it is given credit for, and it is certainly easier to inspect.

I'm also curious how the LN filter ( which I have installed ) is supposed to eliminate bypass since it mounts on the same location as the stock filter. Bypass is usually a function of the oil pressure relief and the LN doesn't touch that.

[Jamesp]

Originally Posted by flaps10

filter is better than it is given credit for, and it is certainly easier to inspect.

I'm also curious how the LN filter ( which I have installed ) is supposed to eliminate bypass since it mounts on the same location as the stock filter. Bypass is usually a function of the oil pressure relief and the LN doesn't touch that.

Apparently the stock filter housing has a spring and plate in the bottom that also acts as a bypass if the oil is cold enough. My rod and crank bearings were also worn, but evenly (not scratched) from 120K of freeway driving. The chips never made it past the filter in my case.

[JFP in PA]

Originally Posted by Jamesp

I'd like to see the numbers on that. I did take mine apart and cleaned it with solvents, not ultrasonic. My sense is the stock oil filter does a better job than it is credited with as has been amply demonstrated when they are cut open. What do the chips take out? Seriously, provided the oil filter does not fail, they go through the oil pump and end up in the filter. If they are too big, the end up in the pan. The death blow isn't the chips, its the damage that created them. Now if an open bearing is chosen as an IMSB replacement using unfiltered oil, the story changes.

Obviously, I cannot speak for all attempts at this, but we have had three customers that had IMS failures (which we identified in the shop by pulling the sump covers) that then subsequently undertook DIY retrofit and multiple oil flushes (no engine disassembly), and none of them survived more than 200 miles.

You case is somewhat different in that you at least tried to mechanically remove as much debris as possible before returning the car to service. Most people actually do not attempt that.