I would like advice in selecting the right bearings for a pool pump motor.

About two years ago, the KBC Korea 6203D bearings that were removed were
not the original bearings on this Max-e-Glas II pool pump with an AO
Smith QC1102 square flange 48Y 1.0x1.65HP 240 volt single phase induction
motor.

I had replaced the Korean 6203D bearings with USA NSK 6203V bearings, but
even they didn't hold up as well as I would have liked.

The US Seal PS-201 pump seal was replaced in both instances, and no
evidence of water leakage is apparent (no white crud on the bottom of the
motor).

What bearings would you use that may hold up better under the
circumstances?

On Sat, 05 Nov 2011 02:13:17 -0400, gfretwell wrote:
NSK is a Japanese company (Nippon) and the bearings have been made in
China since the Clinton administration

This is interesting data.

I have the two bearings in my hands. Guess what?

One has molded on the rubber seal at the 12, 6, and 9 o'clock positions:
* NSK 151 6203V USA where the tiny 151 (date code?) seems to be stamped.

The other bearing, unexpectedly, has all four sets molded:
* NSK 800 6203V China where the tiny 800 is molded in (verrry small!)

Is this a shielded bearing (metal race guard)
or a sealed bearing (plastic race guard).

I do not know.

The black rubber (seals?) on each side are visible. I do not see any
metal or plastic shielding on the outside. Do I need to pluck out the
black rubber seals to see below to answer your question?

Googling for the difference between a seal & a shield, I find:
http://www.dynaroll.com/shields.asp

Which says "a shield (non-contact) or seal (contact) retains lubricant
and prevents contamination from entering the bearing raceways".

You want a sealed bearing.
I think, so far, I MUST have at least a 17mm bore double-sealed bearing.

Other than that there are lots of grades of 6203 bearing

I see that!

Googling, I find the following types for 6203 bearings:
6 = metric sized, single row, deep groove
2 = light duty (i.e, 40mm OD, 12mm thick) == I think I can go larger
03 = 17 mm bore diameter == this is a critical dimension

These seem to be the designations I can decipher so far:
D = molded Buna-N rubber lip seal with a steel insert which provides
maximum protection against contamination; however, the high pressure of
the lip seal itself results in greatly increased torque and friction
losses that can cause heat build-up in higher speed applications. The
seal material itself is rated to a maximum of 250 °F
S = same as D except it's non contact
DD = same as D but double shielded
M = brass cage
V = single, contact, nitrile rubber seal (keeps fluids out)
Z = single, staked, non-contact shield of 300 series stainless steel.
LL = ? seems to be the same as 2RS ?
NR = snap ring and groove
RS = single nitrile rubber seal
TS = glass reinforced teflon giving good contamination protection
VV = double non-contact seal
ZS = same as ZZ but retained by a snap wire
TTS = same as TS, but double shielded
ZZS = same as ZS but double shielded
ZZ = double, staked, non-contact, 300 series stainless steel shields
ZZA = removable shield
2RS = double nitrile rubber seals
DDU = double contact seals (apparently similar to 2RS)
2RSC3 = ?

SOURCES:
http://www.gizmology.net/bearings.htm
http://www.dynaroll.com/shields.asp
http://www.dynaroll.com/selector.asp
http://www.bearings.machinedesign.com/BDEList.aspx
http://www.top-bearing.com/news/?p=407
http://www.ntn.ca/pdf/2200/dimcodes.pdf
http://www.mcmaster.com/#6203-ball-bearings/=espnpe
http://www.motionbrgs.com/basic_brg_info.htm
http://www.skatebearings.com/6200-series.htm
http://wetheadpumprepair.com/6203-ll...motor-bearing/
http://www.nmbtc.com/bearings/part-numbering.html
http://www.skf.com/skf/productcatalo...lationsFilter?
lang=en&newlink=&prodid=&action=Calc1

O

The black rubber (seals?) on each side are visible. I do not see any
metal or plastic shielding on the outside. Do I need to pluck out the
black rubber seals to see below to answer your question?

Do not pluck. If you see black rubber it is sealed.