Stoatmaster

Thanks guys, I ordered the bearings and one has turned up.

Been too busy with work but will hopefully have a stab atxit this weekend. The pulleys themselves look a bit tired so I'll clean them up and repaint them while I sort the bearings out.

I replaced the belt with an OEM, and was surprised with the amount rattle on the tensioner pulley so it's well due a change.

engifineer

As a general note, anytime a sealed bearing fails in anything, take the time to see what it takes to pull and replace, and then find a part number stamped on it. Most of the time a sealed bearing is a standard part that can be found. Good example is my dads motorcyle. He is a mechanic, and had a final drive issue on one of his bikes, so he tore it down. Called to get the bearing and was told "we dont sell that bearing, you have to buy the unit for $800"... he then pulled it apart further, saw the standard part number and mfgr on the bearing and now has a bearing sitting in his shop to repair it for about $30 Same bearing, same mfgr of bearing, just not sold by Kawasaki since they can try to sell you $800 worth of parts instead of a $30 bearing.

noodels

All parts have a generic / spec in manufacture
all come from a BIG book

Capt A

One needs to be a little careful when it comes to bearings. What's marked on a bearing isn't normally the full specification of the part. For example, the correct and full designation for a bearing in a say the drive end of an alternator might be B20-168DDU8T1XCG14 AV3S. This bearing would appear similar to a standard bearing but it would have special ring dimensions or tolerances, a pair special acrylic rubber seals, a special plastic cage, a special radial clearance grade and a particular grease type and quantity. This complete designation would be shown on the packaging only which the alternator maker has long since thrown away. What might be shown on the outside of the actual part (apart from makers name and the country of origin) could be limited to the names of any standard component parts or mould-tooling that is used in the manufacture of bearing assembly. In the case of the above alternator bearing you might see for example '6204' on a ring and perhaps a "6204DU" on each of the seals. Take this info along to your local bearing distributor and he might sell you a "6204DDU". Almost certainly this would be an attractive price and will fill the hole, but it would never meet the car makers component validation test.

Quite often you might get away with using a 'near equivalent', and sometimes you will have no choice if the original part is no longer in production. But sometimes it just wont be near enough.

mysteryjedi

I've got a grumbling idler pulley bearing and would like to replace it, but there's a load of different options. I know I need 6203 2RS but I don't know what any of the other designations mean, or who makes good bearings, whether to go branded/unbranded etc. Prices seem to vary from £3 to £13 so not a deal breaker - just want to get the right part for the job! Anyone more knowledgeable than me able to shed some light or recommend what to go, or not go, for?

Sites I've been looking at...

https://simplybearings.co.uk/shop/ad...ds=6203%202RS&

https://www.bearings-online.co.uk/browse/q-6203/q-2RS

https://www.bearingboys.co.uk/Dunlop...-x-12mm-1891-p

https://www.bearingshopuk.co.uk/cata...lt/?q=6203+2RS

https://www.onlinebearings.co.uk/620...g-Branded.html

engifineer

This is what a lot of us on here have used. Mine have been in for a couple of years now and working fine.

BenRNBP

You want one rated to something over 14000rpm ( around there anyway, I'm sure someone did the sums on it) that Nachi above is rated at 18K so you wouldn't really go wrong with one of those https://simplybearings.co.uk/shop/p2...duct_info.html

I didn't know this when I bought mine and went with the SKF 6203 2RSH C3 and it's been fine for years. They have an explanation of C3 and what it means - not sure it's needed, but at the time I thought it was was a hot and fast application and there's no axial play that I can feel https://simplybearings.co.uk/shop/in..._explained.php

mysteryjedi

Thanks for the reply, have gone with the suggestion below as a UK supplier will hopefully make things easier! :-)

Cheers for this, just what I needed! :-) Have order 2x the Nachi ones! :-)

baldspot_lol

recently had an issue with the aux belt/ idler pulley on mine too (36k miles) symptoms was a kind of intermittenty hissing noise at the aux belt, the pulley wasnt smooth where the belt rides and had some kind of deposits on it, bits of old aux belt i assume.

anyway as it was sunday and i wanted a part to take the car to work tomorrow, i got this
https://www.eurocarparts.com/search/...SABEgIAwPD_BwE
and this
https://www.eurocarparts.com/search/...SABEgI1DfD_BwE

from eurocarparts. neither is listed as fitting the S, but they're what comes up with the relevant google searches. the belt is the right one and fits straight on, but you'll need to change the bearing on the pulley as its not right, but the bearing is correct. easy job with an old vice an a couple sockets, the new bearing has to be cut out of the new pulley as its mouled into the plastic, but a hacksaw makes this a 2 min job, get it nearly there and crack it in 2 with your hands.

of course, the right way to do it is to order the correct bearing as above, but if its sunday afternoon and you just want the job done, this works fine.

jsaric

Hi.
Bringing old topic back.

​​​​​​Just want to check with you as i'm not sure.

I have avaliable localy:
​​​​​​Skf 6203 2rsh 12k rpm rubber seal
Skf 6203 2z c3 19k rpm metal seal
Skf 6203 2z

Which one should i choose for idler pulley and tensioner pulley?

I read that it has to be ok up to 14k rpm, so 2rsh worries me a bit as it is stated it's only 12k rpm.

Thanks