951 counterballance rebuild

[Mekanix]

Just started rebuilding these.

Wondering what people use for bearings.

Currently I'm using ntn. But I've removed skf and other "no name brands". (Edit: unreadable bearings )

Looking for reliability.
I've seen 4 failed shafts this year, not sure why they failed either, no signs of a problem.

On a good note. They pressed apart very easily.

Also what do you guys prefer for gear oil ? Haven't looked through the manual or threads yet but in the process of it.

 

[statikuz]

I used this because that's what I had from changing pump oil.

Synthetic SAE 75W-90 Gear Oil

 

[Mekanix]

That's what I use in the pumps as well.

 

[racerxxx]

SKF is not a no name(I know you didn't mean it that way). They're the only bearing I'll use in these engines. It's very difficult to find them with the composite cage but I'll by on eBay when I need them. Honestly the dealer is sometimes cheaper than my supplier.

 

[Mekanix]

Why those specific ones with the composit cage? Vs steel cage I mean. I have done two with ntn so far and I'm wondering if that is a mistake. I have one more to rebuild and I'm out of bearings.

 

[racerxxx]

Look at the specs. IIRC the composite caged bearings had an rpm rating that is almost twice a standard metal caged bearing.14,000rpm or something like that. It might also have a lower friction rating. My local bearing house I use said it's a very nice bearing but no one here in the states would pay for it, I think they're typically double to triple the price.

 

[Mekanix]

Hmm the specs on these from ntn say 14000 rpm not much more.

After seeing 4 failed counterballance shafts in 951's this year I'm wondering if it's a matter of time or if it's the quality of the part.
I pulled a 2003 rx oem shaft apart that had skf with steel cage. Also have another with koyo that failed hard...

 

[racerxxx]

Interesting. The 951 CB had sealed bearings iirc. If so those will have a metal cage not composite. They're permanently lubed since they see no oil from the engine.

 

[Mekanix]

Yup, they are sealed with (non contact seals )
Last rebuild I did had good feeling bearings with 100 hrs but still failed and damaged the cases. And I'm not sure why yet. So now I'm just replacing them just because.

 

[DanSquires]

I use Nachi unless skf is requested. And they're pricy items.
Really the only time i come across bad bearings on 951 engines are from water, or on di the compressor side bearings which are not sealed.

 

[Mekanix]

These ntn's were 30 a piece, but also said made in taiwan.

 

[drjack]

Was SKF bearing always installed originally? Im about to order bearings, and considering these shafts spin at 6000-7000 rpm you want something that can take the punishment. Anybody can supply a shaft with "new bearings" installed but if they're cheap no names, it's only a matter of a few hours before they grenade.

 

[drjack]

And the needle bearing NK 22/16 is SKF ?