Rod Bearing Wear Pics

[Yamaha V6]

Pulled this weekend from an engine being prepped now, reportedly 68k miles. Heavy caramel coloring in the heads.

The donor 3.0L for the swap had a reported 50k; its bearings were great, and had virtually no caramel coloring.

 

[shoinoff95]

I had my rod bearings replaced and mine looked about the same as in those pics. Mine looked about like the ones on the top, but not as much copper showing!

 

[Mike Kopstain]

Wow, for an ATX that looks more like what you would expect at 168k rather than 68k.

 

[MilTownSHO]

I really want to do mine now, with all these recent failures, its like a new epidemic, expect its not cams, now its rod bearings... jpshakeh

 

[AutoSHO]

Wow!

I'm going to hazarda guess that the engine had very insufficient oil changes, and was probably driven overly hard, especially while cold.

 

[Shoaz]

Eep!

I'm going to hazarda guess that the engine had very insufficient oil changes, and was probably driven overly hard, especially while cold.

Yeah, the caramelling is a hint.

Old oil or it really had a lot more than 68k miles.

Or both...

 

[shojuan]

MilTownSHO:
I really want to do mine now, with all these recent failures, its like a new epidemic, expect its not cams, now its rod bearings... jpshakeh

Heehee, I got bearings in the mail for both my truck and my SHO. Rods AND mains. The truck needs the mains done too. The SHO? Well why the **** not? Why not spend twice the money, twice the time, and twice the cussing? Lol, that's me for you. Put a few extra dollars into my pockets and it starts digging holes.

 

[sdpatt]

Those bearings look quite similar to the ones I removed after 269,000 miles in my engine (below). That is significant wear for that low a mileage.

 

[Yamaha V6]

Exactly Scott - I'm not seeing a direct correlation between mileage & bearing wear. Given I spun my 95's at 72k (purchased at 58k), and this one at 68k, yet others at 160k+ that are decent looking, I'd suggest to anyone buying a SHO to make this one of the first things you do.

Tax, Title, Registration, Inspection, Rod Bearings.

Anyway, I'm going to ask Beth to put make a new sticky thread for bearing pics (like the dynograph pics). We'll post the pics of bearings as they come off, and hopefully as much maintenance & driving style info as possible, to see if we can nail down a common factor, such as oil type, etc.

 

[NotSoSlowSHO]

Yamaha V6:

Anyway, I'm going to ask Beth to put make a new sticky thread for bearing pics (like the dynograph pics). We'll post the pics of bearings as they come off, and hopefully as much maintenance & driving style info as possible, to see if we can nail down a common factor, such as oil type, etc.

While your at it...

How about a cam lobe pic sticky as well, with similar data shrug thumb

 

[Yamaha V6]

MilTownSHO:
I really want to do mine now, with all these recent failures, its like a new epidemic, expect its not cams, now its rod bearings... jpshakeh

Just to set the record straight here, the bearings shown have not "failed"; they did not spin, nor is there any crankshaft damage. They ARE worn more significantly than I would like to see for a low mileage SHO engine, and I would imagine that they would be far more likely to contribute to a bearing issue farther on down the line.

One other thing: in the case of an engine refresh or 3.2L swap, there is NO reason not to pull them out to inspect, or to simply replace them. Dry-firing thes bearings (after the engine's been out for a year) would likely have contributed to a large problem later. I know of one guy's engine here who very likely did just that.

 

[drivinhard]

Actually those aren't too far of what I've seen typical for a 3.2L motor (60k-100k range). The 3.2L's seem to be harder on the bearings vs a 3.0L, possibly due to the ATX/EEC tending to keep the revs down where oil pressure isn't as high, and also the 3.2L's are using the same bearings as the 3.0L, but with a heavier rod and piston assembly. That and the 3.2's make more torque (more downward stroke stress)

I for one don't buy into the "driving it hard = extreme bearing wear" on these motors. I've re-done too many engines that spent lots of time on the track that had very minimal bearing wear. I've seen good results with Valvoline, Mobil 1, and Castrol GTX. I wouldn't personally mess with rod bearings unless you are over 200k and/or the motor is in poor shape. It's cheap insurance if you like to tinker with cars, but no reason to get paranoid about it.

If you are freshing up a motor for a swap on the stand, then it's easy to do, sure go for it. No need for everybody to run to the driveway and start ripping off oil pans though.

<small>[ June 25, 2003, 01:30 PM: Message edited by: drivinhard ]</small>

 

[gosho89]

If a person is consurned about the bearings they can always do an Oil Analyst as a precautionary measure. This process, also known as Oil sampling is used by many larger truck and Heavy equipment fleets. The feedback can assist in determining a needed repair to the equipment before it fails. Lets just call it a early warning system to what could lie ahead. eek! Personaly I have my engine on this program, its very affordable and gives great feedback with explanation of wear materials and other particles found in the old oil. thumb

 

[NotSoSlowSHO]

It is so easy and inexpensive to replace rod bearings that I figure it is just a good precautionary measure to take while you are doing a 60k, or for those that havnt upgraded to oa y-pipe, when they replace the y-pipe.

Shoot, all you have to do to get to them is remove the y-pipe, starter, and pan shrug

 

[Yamaha V6]

I'm paranoid for only one reason Mark: First-hand loss.

At 72,000 miles I lost my 3.0L to spun bearings, and my cost to replace was astromomical. Granted, I could do the same built-engine replacement today for a third of the cost (or less), but the point was, for the want of less that $100 worth of parts, the engine was lost... And for me, one lost engine is one too many.

I'm sticking with the "think about it at the 100k-120k range, or before major power adders" advice. We've got people here who are doing 3.2L swaps now fairly commonplace. Let's get the word out to them to replace these parts. As I understand it, Edien (RI-SHO) lost his 3.2L 700 miles after the swap-in to his new car, possibly to bearing failure (to my knowledge, the pan hasn't been pulled to verify this yet).

I completely respect your point of view on this Mark, and as we've discussed in the past, about the low-rpm / low oil pressure premise. You're the guy that turned me on to this issue in the first place a couple of years ago, and you've got far more hard miles under your belt than I do.

Pardon the generalization folks, but with the "kids" buying these cars, soaking every dime they have into them, a bearing / engine failure can be a devastating loss. And, with the values of these cars being what they are and declining, a dead-engined SHO effectively is going to total it if they're not doing the labor themselves. If we lose 5 forum members' engines this year due to bearings (and I think that number would only go up as the cars age), that's still a considerable number, due to the economics involved. Sure, five out of (how many actual active members here?)isn't a high percentage, but who wants to be one of those five?

Some instructions have been posted up here, along with the costs & list of parts. It requires basic hand tools only. Whether you have someone do it, or do it yourself, I think it's a prudent thing to do the maintenance. If you plan on the SHO going to last 200k, or if you know you're going to suddenly change the working conditions the engine's been subjected to, doing it at 100k or before the power adders doesn't seem all that unreasonable to me.

That is, of course, just my opinion.

 

[drivinhard]

Don't think the blower had anything to do with that do ya? lol

For power adder addition, sure change the bearings. I did the same when I did my 3.2L build a few years back (knew I was gonna be beating on it with N20). And for 3.2L swaps with them on the stand, sure, too easy not to.

But for mostly stock cars in my experience it's not a REAL big issue.

My 92 has 175k or so on the motor, and up until a few weeks ago when a PP ypipe cat broke up and sucked itself into the motor, it was as healthy of a motor as you can get. (I'm more paranoid about cats breaking up than bearings going bad, lol) The beater motor has 225k+ on it, original bearings. Maybe not a bad idea to change but I haven't worried about it.

Will be curious to see what the bearings on the 92 look like at 175k with lots of drag and open track miles on them.

 

[billh]

If you put a bearing micrometer on those bearings, you will find that there is very little actual wear. My bearings looked pretty much the same and wear was in the .0004 to .0006 range. The problem with this is that this extra clearance is at the very spot where it can do the most damage. Oil only has so much film strength. When that film strength breaks down due to excessive clearance, you get metal to metal contact and a spun bearing.
We had a problem with our SS engines spinning the rod bearings and exploding the engine. We solved it by re-conditioning the rods with a .001 shim between the cap and the rod, then removing the shim. This made the rod .002 out of round at the parting line. At 8000 RPM, everything was pulled round again. No more spun bearings. (Not for street use) wink

 

[drivinhard]

"If you put a bearing micrometer on those bearings, you will find that there is very little actual wear."

Yep, and if you measure the clearance, and measure the clearance of new Clevites, 9 times out of 10 it'll be looser The clevites fit a tick looser than the OEM Ford...

 

[yamahaSHO]

Looks like that motor has seen lots of hard acceleration wink
Wouldn't have it any other way....