For those who have actually put real mileage on your cars...

[GavinT]

The stock inner bearing for the S2 (with a shaft turned down to 30mm) is a 6006 - 30x55x13mm
Swift (and presumably David A) is talking about the double row 3006 - 30x55x19mm, so 6mm wider.

Here's a listing but it's in France.
https://www.123bearing.com/bearings-3006-2RS-INA

A supplier in the US – no stock but an invitation to call.
https://www.locateballbearings.com/ina-3006-2rs-double-row-ball-bearing/

Probably one of the less common bearings but presumably 'orderable' from a reputable bearing supplier.

[TurboFource]

They are both the same size on a Special.

[BDA]

I just chatted with a guy at the locateballbearings outfit. They have them in stock for $38 ea. Here is the technical information:

SPECIFICATIONS
Bore Type Round Bore Diameter 30 mm
Outside Diameter 55 mm
Overall Width 19 mm
Closure Type Double Sealed Row Type & Fill Slot 1
Internal Clearance CN
Operating Temperature Range -40 to +210 °F
Cage Type Sheet metal
Dynamic Load Capacity 2990 lbf
Static Load Capacity 1866 lbf
Precision Rating ABEC 1
Seal Type Contacting seal
Finish/Coating Uncoated
Bearing Material Bearing steel
Cage Material Bearing steel Inner
Ring Width 19 mm
Outer Ring Width 19 mm
Fillet Radius 1 mm
Maximum RPM 8000 RPM
Series 630
Weight 0.39 lbs

I’d have to check but I think the load ratings for that bearing is lower than the SKF single row bearing of that size.

[BDA]

Here is the technical information on the SKF 6006-2RS:

Bore Type   Round
Bore Diameter   30 mm
Outside Diameter   55 mm
Overall Width   13 mm
Closure Type   Double Sealed
Row Type & Fill Slot   1
Internal Clearance   C3
Operating Temperature Range   -40 to +210 °F
Cage Type   Sheet metal
Dynamic Load Capacity   3100 lbf
Static Load Capacity   1870 lbf
Precision Rating   ABEC 3
Seal Type   Contacting seal
Finish/Coating   Uncoated
Bearing Material   Bearing steel
Cage Material   Bearing steel
Inner Ring Width   13 mm
Outer Ring Width   13 mm
Fillet Radius   1 mm
Maximum RPM   8000 RPM
Series   60
Weight   0.29 lbs

As you can see, the load ratings are a little bit better for the SKF bearing.

[jbcollier]

Further, the SKF 3006 is a double row, roller bearing, not a ball bearing.

[SwiftDB4]

The 3006 2RS  double row ball bearings I bought are Amcan (Chinese).
https://www.locateballbearings.com/amcan-3006-2rs-angular-contact-ball-bearing/
I don't think the inner spacer would need machining, but the shoulder of the axle would by 6 mm.
Basic static radial load is 3465 lb.
Dynamic radial load is 4477 lb.
7400 rpm limiting speed

[BDA]

Swift, where did you get that data?

The data in reply #62 came from a chat session about the 3006-2RS.at the link GavinT gave. I went to https://amcanbearing.com/ and their site is user hostile or at least I wasn't able to find any information at all on the 3006-2RS.

[jbcollier]

I'm not a big fan of off-brand Chinese bearings.  Just seen too much junk.  I have used extensively, and trust, bearings by SKF, FAG, NSK, and a few others.

[BDA]

Chinese bearings turn me off and to have a dynamic load capacity of only about 10% more than the correct SKF bearings (which assumes that the information I received was erroneous) makes it not worth the risk for me.

[SwiftDB4]

I got the bearing data from:
https://medias.schaeffler.us/en/product/rotary/rolling-and-plain-bearings/ball-bearings/angular-contact-ball-bearings/3006-2rs/p/360382
I also understand concerns about Chinese bearings. If SKF, NTN, NSK, etc. bearings in the 3006 2RS size are available by all means they would be preferable. I only bought the Chinese ones to see if it was possible to use a double row inner bearing. The narrow standard inner bearing and subsequent housing wear are a definite weakness.

[BDA]

I just came back from my engine builder friend's (Dennis) shop. He measured my upright to make sure the bearing bore was round (enough) and small enough to provide the proper fit. He thought it did so that was good news.

When I got upright, stub axle, and radius arm back from the shop down the street, I notice that the spacer was in two parts (the long part is 2.0233" and the short part is 0.126"). Since I'm using TC (not Special) rear suspension parts, the spacer I need is 2.125" long. A keen eye will note that there is no combination of those two spacer parts that adds up to 2.125" /-0.010". Dennis further examined the bearing bore for the inner bearing and it appeared that the bearing had not been seated entirely in the bore. In fact, he noted a small patch of rust on the outer race confirming that. It was apparent that the spacer I had was too tall and that was likely the source of my problem. I'll remind everyone that my bearings seem to be in good shape (other than the small patch of rust on the inner bearing). There is no roughness when turning the bearings and the seals appear to be intact. I don't know how many miles are on those bearings but they seem to have a lot of life left in them.

In my defense, I did not assemble my uprights. I believe they came from Richard's (at Banks) shop and maybe someone who was not careful put them together. Regardless, I'm pretty comfortable that Dennis' analysis is correct. Not taking anything to chance, I did some measurements to ensure that the 2.125" spacer was the correct one (it is longer than from the inside of the outer bearing to the shoulder of the bore for the inner bearing and when assembled, the entire inner bearing should be in the bore).

So I'll be ordering the rest of the parts I need and get on with putting things back together. To that end, I'd like to find some Loctite to use on my bearings. Some I've seen require a fair amount of heat to disassemble the part. Can anyone suggest a Loctite (or similar product) to help hold the bearings that does not require a lot of (any?) heat? Would regular blue Loctite work?

[jbcollier]

The outer bearing is fixed in place by the housing and the brake plate.  The inner bearing does not go all the way into the housing.  It is located by the spacer between the two bearings.

The inner bearing is not too "narrow". It is too small in diameter.  Outer 62/30, inner 55/30(31).  This means it uses smaller balls for a lower load rating and faster ball rotation speed for any given shaft rotation speed.  This is why the inner bearing fails far more often than the outer.  Ball bearings also have essentially point contact which is why there have a much lower load rating than tapered roller bearings.  Look at all the trouble in the rear while then front with dinky tapered rollers is no problem at all.  I'm thinking it may be time to switch to tapered...

[TurboFource]

As I mentioned before, my plan too JB!

[BDA]

I haven't posted an update to this in quite a while and I found something significant that I didn't notice before my previous update. See the picture below.

I think I described everything else in my previous update (reply #70 on the previous page): bearing bore in good condition, stack of spacers taller than the 2.125" called for, both bearings good. Other than the wear on the stub axle, the other thing I didn't note was that Richard had sleeved the inner and outer bearing bores with aluminum. That appears to have been a quality job based on the measurements Dennis (engine builder buddy) took.

The spacers would have kept a small amount (don't remember how much but nowhere near 1/2 thickness and I'm pretty sure much less than 1/4 thickness) of the bearing outside of the bore - so the entire thickness of the inner bearing could not have been in its bore. Measuring everything, the correct 2.125" spacer would allow the entire bearing to seat in its bore. I ordered a set from r.d. enterprises. They are very thick so when I get around to reassembling everything, I'm going to make sure that any offset in spacer doesn't beat my upright up.

The stub axle nut was torqued and locked by drilling and tapping an axial hole along the threads and a set screw screwed into it so the nut did not back out. It's pretty clear that the wear on the stub axle is caused by some misalignment. I'm at a complete loss what could cause that misalignment if it wasn't because of some problem with the inner bearing but, as I say, there is no evidence of any distress in or around the inner bearing bore that I would expect to accompany a loose bearing.

Now I have all the parts I need and I'm wondering if anybody has any tips on reassembly. Does anybody use Loctite or other retaining compound on the bearing bores (there was what looked like red Loctite in the bores after the bearings came out. This was apparently put in by one of Richard's minions.*) I got my new bearings from a bearing house and the only thing the guy there would recommend is Loctite 660 (I believe that was the number) for damaged bores and my bore is not damaged. All the retaining compounds I found are high temp and apparently require heat (much hotter than the hot water called for in the manual when disassembling the upright).

* A thought just occurred to me about whatever compound was used to retain the bearings. My uprights were assembled in the UK. Tightening the stub axle nut means that the inner bearing will move till it contacts the spacer (which we know was too long) but whatever they used would certainly have set by the time I got it and whatever adhesion was there when it was assembled would likely be broken when torqued. So what was the idea for the compound used in the inner bearing bore? (I hope that makes sense!)

[SwiftDB4]

Not sure if the axle wear was due to misalignment, but I have had the same problem on the outer bearing axle journal. Axle alloy is too soft, but most importantly half the journal is on the splines. I have questioned before why axles couldn't be machined with shorter splines leaving a full journal for the bearing. Someone said it would be too much to ask for, but I don't buy that. As far as I know this axle is only used on Europas, Hillman Imps, and some vintage formula racecars. Surely machining shorter splines can't be that big a deal. In addition TC axles are not used on any other vehicle. The custom axles from PA Motorsports appear to have a full journal for the outer bearing.