Another perspective on main bearing failures

[spammysammich]

https://www.youtube.com/watch?v=EufA...rintechCustoms


This just popped up in my recommendations. We're definitely becoming more aware of this issue on this forum. Now, what to do about it?

[Glacial Pace]

Originally Posted by spammysammich

https://www.youtube.com/watch?v=EufA...rintechCustoms


This just popped up in my recommendations. We're definitely becoming more aware of this issue on this forum. Now, what to do about it?

Not a huge amount that can be done about it. Replacing the main bearings is a huge job, and one that is almost certainly not financially worth doing on a large amount of cars.

[RocketyMan]

Originally Posted by spammysammich

https://www.youtube.com/watch?v=EufA...rintechCustoms


This just popped up in my recommendations. We're definitely becoming more aware of this issue on this forum. Now, what to do about it?

Neat video! Yeah I agree with the video. I like the "sleeved" steel insert approach on main #1. I wonder how much they'd charge for that service. Too bad they're not in the states.

[drwankel]

Interesting and horrifying. Surely running a supercharger couldn't make this worse.... right? right?

Here's my take on it. Main bearing replacement on these engines is not anywhere close to preventative maintenance. It's nearly an entire engine rebuild.

I'd just run it until it pops and then put a rebuild in it. People on these forums are passing 200k, and while that video is concerning, people around here arent dropping dead from main bearing failure.

Drive the car. The mains probably do wear, but there just isnt anything you can do about it short of an entire rebuild.

[E92Bean]

It’d help to know the history of the few that have failed. Also the repair seems very high risk for general Indy shops. As mentioned in the video, if the crank isn’t seated properly you’ll brick the engine.

[drwankel]

Originally Posted by E92Bean

It’d help to know the history of the few that have failed. Also the repair seems very high risk for general Indy shops. As mentioned in the video, if the crank isn’t seated properly you’ll brick the engine.

Yeah, if any Indy shop isn't competent in doing full S65 rebuilds, no way they are touching the mains.

Best bet is to get higher clearance mains installed during a rebuild.

Just enjoy the car otherwise. No use worrying about a problem that is rare and you cant really do anything about proactively.

[charliev68]

Out of curiosity…how much would you guys realistically pay (labor only) for a Main Bearing refresh?
To think, one would wait till you spin a main and crack your block and then start all over with a used engine is bananas. I don’t care how complicated or difficult you think the job is!

[E92Bean]

Originally Posted by charliev68

Out of curiosity…how much would you guys realistically pay (labor only) for a Main Bearing refresh?
To think, one would wait till you spin a main and crack your block and then start all over with a used engine is bananas. I don’t care how complicated or difficult you think the job is!

Dug through an old thread from deansbimmer, a shop pretty familiar with the s65. Looks to be an engine out job to do it right, ballpark ~$6k-8k. I found aftermarket main bearings too.
Pricey, but cheaper than a used motor+new rod bearings or a stroker. Maybe if I have my car at 200k+ miles I’d consider it. But for now, I still have a warranty so other than RB’s I’m not touching anything.

[ab987]

Originally Posted by drwankel

Interesting and horrifying. Surely running a supercharger couldn't make this worse.... right? right?

Here's my take on it. Main bearing replacement on these engines is not anywhere close to preventative maintenance. It's nearly an entire engine rebuild.

I'd just run it until it pops and then put a rebuild in it. People on these forums are passing 200k, and while that video is concerning, people around here arent dropping dead from main bearing failure.

Drive the car. The mains probably do wear, but there just isnt anything you can do about it short of an entire rebuild.

Based on what "good" engine mains look like, it probably would. I recall we've seen multiple low mile (<70k) supercharged engines fail on this forum. Too much force pulling up on the front of the crank for how thin the journals are. Pulling up more certainly won't help things.

It's a very similar problem to rod bearings in timing but at a seemingly longer interval, some see it earlier than others, but until we see good engines being torn down without copper showing on the front upper shell, I'm convinced it *will* happen to every S65 given enough miles. As we've seen, that can be 100k, 150k, even 300k, but at that point I think a lottery ticket is in order.

In my opinion, if you plan on keeping your S65 for the long term and you're nearing 150k miles, bite the bullet. Spend the $6-8k at a good shop like deans and don't look back. I'm $30k deep in a used engine and a full Carbahn rebuild, and that's not even a stroker. It's one hell of a gamble, up to you if you want to take it.

[Soden82]

If I keep my car long enough, I would elect to do an engine out refresh and swap in higher clearance bearings, new rods, pistons, etc.

With how scarce parts will become 10+ years down the road, it will be more difficult to source a used/rebuilt block and find the right people to work on it.