are my main bearings starting to go?

[kolosy]

car has 150k miles on it, WPC-treated bearings about 40k miles ago, and sees heavy track use (did ~15 days on it last season, some days being full day private rentals).

i scoped it recently and saw some unpleasant wear, but it didn't look like full-on bore scoring. then I got this blackstone report.



the things concerning me -- steadily increasing aluminum, and increasing lead on a car with aftermarket rod bearings.

i don't use leaded race gas or octane boosters, so that wouldn't be a source of it. car has excellent compression and doesn't use an unreasonable amount of oil (1/2-1 qt per 3k miles).

[M3_Legend]

Damn I wouldn’t take a chance have it inspected better safe then sorry. To many threads laatly about main bearing failure

[kolosy]

You can’t inspect main bearings without splitting the block. Might as well rebuild at that point.

[charliev68]

Time for a refresh! 150k miles is a milestone. What’s your other option…wait til it spins and cracks your block?

[DrFerry]

I'm wondering IF the WPC rod bearings are really the culprits. I could be wrong.. but the WPC bearings are basically OEM spec clearances (which we know are tight). Add to that your Chicago winters, 10W60 and cold starts and... well, you get my point.

[charliev68]

I’ve done WPC on RBs and MBs, went to their factory and saw the process. Nothing is added, all they do is shot blast the bearings to change the surface area. Material is microscopically reduced and the friction area becomes super slippery.

[kolosy]

Originally Posted by charliev68

Time for a refresh! 150k miles is a milestone. What’s your other option…wait til it spins and cracks your block?

basically? i don't have the bandwidth for doing the refresh myself, and it's a track-only car. (also means no cold-weather starts DrFerry ).

gonna talk to my engine builder and see how much they'll want to do it.

[DrFerry]

Originally Posted by charliev68

I’ve done WPC on RBs and MBs, went to their factory and saw the process. Nothing is added, all they do is shot blast the bearings to change the surface area. Material is microscopically reduced and the friction area becomes super slippery.

Thank you. I sit corrected. Getting old these days and thought I recalled them being coated. I’ll edit my post.

[charliev68]

Originally Posted by kolosy

gonna talk to my engine builder and see how much they'll want to do it.

Ask the person that will potentially do the work to “read and follow” Mporium’s MB write up. Do not separate the heads and do not disturb the pistons. You will save a lot of money and labor if you leave that part alone. Trust me!

[kolosy]

Originally Posted by charliev68

Ask the person that will potentially do the work to “read and follow” Mporium’s MB write up. Do not separate the heads and do not disturb the pistons. You will save a lot of money and labor if you leave that part alone. Trust me!

Thanks, good reminder on that write up.

That said, given the wear I saw on the scope, if I bite the bullet I think I’ll want to recondition the bores too.

[darren p.]

Originally Posted by charliev68

Time for a refresh! 150k miles is a milestone. What’s your other option…wait til it spins and cracks your block?

I'm at 155k, no Blackstone reports and VAC bearings were put in at 112k. Have not looked at my cylinder walls with a boresocope. Like kolosy, I'm basically planning on driving it until the wheels (mains) fall off and sourcing a motor from Carbahn after that happens. Is that a bad move? Should I be more proactive? The downside as I see it would be the inability to use the motor as a core? How much extra money are we talking about in that hypothetical scenario?

This is just a street car, have not tracked it yet but am basically building the car up as a street/track car.

[kolosy]

Originally Posted by darren p.

I'm at 155k, no Blackstone reports and VAC bearings were put in at 112k. Have not looked at my cylinder walls with a boresocope. Like kolosy, I'm basically planning on driving it until the wheels (mains) fall off and sourcing a motor from Carbahn after that happens. Is that a bad move? Should I be more proactive? The downside as I see it would be the inability to use the motor as a core? How much extra money are we talking about in that hypothetical scenario?

This is just a street car, have not tracked it yet but am basically building the car up as a street/track car.

not sure what their core charge is, but a "ran when i had it" mystery engine from Ebay can be had for around $5K. figure that's your core charge, or close to it.

[Honda]

I am still not sure why did you conclude it is a main bearing wear from report above.

The report above can be anything from piston wear to any other mechanical wear in the engine

[kolosy]

Originally Posted by Honda

I am still not sure why did you conclude it is a main bearing wear from report above.

The report above can be anything from piston wear to any other mechanical wear in the engine

Where do you see a conclusion of any kind? I have increasing aluminum and lead over 3 samples, and am concerned that it could be the mains because the rod bearings are done, which is why I’m asking here.

[DW_CT9A]

13 events on the same oil? And 150k on the motor? Goddamn, that's wild. Then again, looking at the viscosity test results on that report, it seems like the oil held up reasonably well. Which flavor of 10w60 do you use?

At what mileage did this become a track only car? These are interesting data points. Thanks for sharing.

[kolosy]

Originally Posted by DW_CT9A

13 events on the same oil? And 150k on the motor? Goddamn, that's wild. Then again, looking at the viscosity test results on that report, it seems like the oil held up reasonably well. Which flavor of 10w60 do you use?

At what mileage did this become a track only car? These are interesting data points. Thanks for sharing.

How many track days do you go between changes? Went track only at the start of the blackstone reports, about 147K miles. BMW M 10w60, which is what, castrol under the hood? Or is it mobil 1 now?

[DW_CT9A]

Last I heard it was still Castrol.

Short answer is two days/one weekend with a robust group IV or group V based synthetic. But all my Blackstone results that brought me there were not from an S65. And I never tried pushing it longer than 2 days.

Here's a UOA from my Evo. This represents only two track days and some easy street miles. Granted this engine is different and has half the oil capacity.
Additionally, Mobil 1 15w50 is a hydrocracked group III bullshit oil these days. But still, cst viscosity @ 100C is 18 on a virgin sample. My sample sheared down to half that. After this, I tried it again with only 1 track day and very few street miles and the viscosity was much more favorable. Later I switched to a much better ester based oil. (Redline 15w50)

[CamasM3e93]

Originally Posted by DW_CT9A

Last I heard it was still Castrol.

Short answer is two days/one weekend with a robust group IV or group V based synthetic. But all my Blackstone results that brought me there were not from an S65. And I never tried pushing it longer than 2 days.

Here's a UOA from my Evo. This represents only two track days and some easy street miles. Granted this engine is different and has half the oil capacity.
Additionally, Mobil 1 15w50 is a hydrocracked group III bullshit oil these days. But still, cst viscosity @ 100C is 18 on a virgin sample. My sample sheared down to half that. After this, I tried it again with only 1 track day and very few street miles and the viscosity was much more favorable. Later I switched to a much better ester based oil. (Redline 15w50)

Two track days on a high quality 10w60 oil change for an interval is excessive for the s65, imo but backed up with my own testing. Last season I think I did around 15 days with one change mid-season and one at the end. Perfect oil reports and viscosity saw no dropoff with the regular (not track spec) Motul 10w60. This was a supercharged car with 140k miles. I have run redline 5w50 in the past with excellent results but it was challenging to source earlier this year and BE explicitly advocates for 10w60 on their aftermarket shell. So motul it is

I have oil reports on other cars with different engines and different oil grades. I wouldn’t apply any of those learnings to a different platform. Say what you will about 10w60 and the S65 but being hard on oil isn’t actually something I have seen with this car.

[t5motorworks]

Personally, wouldn't worry until copper starts to increase. If concerned throw a mechanical oil pressure gauge on it. Worn main bearings will make oil pressure drop significantly.