Odd noise from engine?

Here is some information for anyone in the future.

The originally installed bearing in the power steering belt tensioner (in a Suzuki Jimny with M13A VVT engine, made in 2013) is NSK "6010DU2".

The bearing has rubber seals on both sides.
Specifications are: single-row, ball bearings, deep groove, 50 x 80 x 16 mm

NSK has allegedly superseded it by the bearing model "6010DDU":
www.jp.nsk.com/app02/NSKOnlineCatalog/en...B_SR_DD&yobi=6010DDU

However, since the specifications of those two bearings appear to be the same, it could very well be the same bearing, but just a changed naming nomenclature.

Anyway, this is probably the bearing which Martin sells.

P.S.:
I have also found a "premium" edition of this bearing. It is NSK "6010VV".

The "VV" suffix means that is has special "contactless" double sided rubber seals (and made of some super tech rubber), which effectively allow far higher bearing RPMs and operating temperatures. However, this premium bearing is about 3x more expensive than the "ordinary" one.

The salesman from the NSK dealer persuaded me that I have no need for the premium bearing for my application (although I told him that it's an all terrain vehicle which drives through dust and mud and gets stomped hard on the throttle hitting 6000 engine RPMs often).

However, if someone wants to indulge themselves with this premium bearing edition, then buy NSK 6010VV.

I attached some technical literature for reference.
I suppose this is an overkill in writing, but I'm an engineer who first wanted to be a literature writer - I can't help myself!

I replaced an eBay bearing with an OEM one from a donor engine when the previous original expired & was replaced with the one from the 'bay which screamed at the top of its voice after one winter. Suffice to say, I didn't realise the said bearing had a speed restriction.....in your calculations have you an idea how fast that bearing is rotating at say 4500 revs engine speed, & is the power steering pump bearing replaceable ?

Both of your questions are good ones.

However, one thing my mechanic told me (and it makes sense) is that engine RPMs and tensioner bearing RPMs are not the same.
Also, the NSK salesman told me that maximum bearing RPMs from the brochure should not be taken literally, as there is some mathematical factor which should always be counted in (depending on the exact bearing type - there is supposedly a table of coefficients for that). But my knowledge of bearings does not go nearly as deep as that.

Therefore, I can not help much on the first question, except to give my own assumption that the standard NSK bearings 6010DU2 and 6010DDU should probably be sufficient for predicted operating range of M13A engines (up to cca 6500 RPM). But it may not be the case, and it may be the reason why the fail relatively often. I am just thinking out loud.

One things is for sure - the three times more expensive NSK 6010VV bearing should definitely be able to withstand any RPM abuse and still be well sealed (but of course still not well enough to withstand dunking the engine in muddy water!).

I have no clue regarding the power steering pump bearings.

I imagine bearing speed ratings are much like tyre speed ratings- based on continual use at maximum load. In an industrial application where a bearing runs at a continuous speed all day long and you want maximum service life the maximum speed is important. In a car, where you only ever operate at maximum RPM momentarily it is less so. I don't believe the speed rating of the bearing is an issue in this application. When I have replaced them I have not used any fancy bearing and I have not had one fail again.