Rear main bearing fitment issue, photos.

that is not normal, something is wrong with that bearing. get a new one

I have always used Clevite and have been able to push them in without the use of any tools.

Use Nissan bearings, no issues with them.

Agreed, there is an issue with that bearing. If used, it will cause lots'o problems.

Thanks for the help guys.

Everybody around here only carries Sealed Power brand. (Autozone, Oreilly, NAPA, Baxter, Knechts)
Rock auto carries Clevite but i wanted to button it up this weekend.
I'll call the local stealership parts dept and see what they're markup is. They gotta have a set in stock.
12208-02P00, bearing set is listed at 39.80 at Courtesy. If they're markup on a Dist cap is any indication,
Beaverton Nissan will want ~55 for the bearing set.

Heh, well i was close. 52.73 and no local dealers have them in stock, they'd have to come from a warehouse out of state.
The reason the dealers don't stock them according to him is that it's cheaper in parts to replace the whole short block
than to charge a customer labor to do bearings. Wow.

Shazbot.

Orielleys will order clevite for you. they did for me, yes i had to wait a couple days but they got em for me as a rod and main set for like 60 bucks.. but i also have a commercial account and 50% off lol


EDIT: clevite is a branch of Mahle Group (who manufactures the rotating assemblies for F1 and Nascar)

Thanks for the info. I'll probably track down a discount code and get them from Rockauto.

Are you ordering by the proper size by the numbers on the block and crank?

No, i just ordered a "standard" Sealed Power set and not the individual bearings. However…

I was under the impression that if the block/crank hadn't been machined, that a standard set, rather than an optional undersized set
would work. Options of 0.25/0.50/0.75 mm undersized is what i can find. Even if the block had been line bored, the thickness of the
rear of the block, where the bearing is binding, would remain the same thickness correct?
Undersized bearings are only required when the crank has been machined correct?

When i ran into this problem, i started educating myself and found that the crank and block are indeed stamped.
The crank is stamped 111 (It's only stamped to 3 places)
The block is stamped 2222
According to the fiche/FSM charts, that translates into STD3

That works out to be
12207P front 12214-02P03
12207 center 12230-02P03
12207M rear 12261-02P03

That's fine if i wanted to order the individual bearings from Nissan (which i may have to do)
but, what if i wanted to order a bearing set (like the Clevite set that Andrew mentioned) from a parts store,
what does STD3 mean? How would that translate into aftermarket bearings. I can't find that information in the FSM or fiche.

I have a set of.clevites in the garage in the box still. I ordered them through my machine shop and I think they only cost le 40 bucks? If you're coming through this weekend hit me up.

if you order aftermarket bearings they do not have the option of a grading system like oem does. you would only order different sized bearings if your main journals or rod journals are out of spec. look at the FSM and measure everything and make sure its within the tolerances that's stated.

Thanks for the great info. I've been reading up on the process where i can on the internets.
This is my first foray into a VG30 bottom end…giggity.
Me and a friend did his 20R in his HiLux pickup probably 20 years ago.

i would be more than happy to help you out on this. if you have any questions with anything just PM me. but it looks like you have a good understanding of things so far

Also, remember that the front main is wider than mains #2 and #3 by about a mm or so. Be carefull where you stick the first 3 main bearings as they will all fit, but the wider will rub the roll fillet of the crank and make it hang up. I ran into this issue with an OEM Nissan bearing in the wrong box. Just something to be on the look out for.

Also, the OEM bearings will have different numbers on the actual bearing shell than the box. Don't know why, but they do.

Also, after what ever bearings you get, make sure you Plastigage the mains and rods to make sure you are within specs.

A couple of things… Why are you sliding the bearing on? Why not press it down from the top? Of course the old bearing will slide on easier. It has been there since the Age of Aries.
2nd- pay attention to the fillet radius on the crank and the chamfered sides of the bearing journal. it could be that the bearing you have is machined so that one side has a more shallow tapered corner on the back side of the bearing.

I do recall having a similar issue. I believe I just turned the bearing 180* and installed that one on the top side/girdle, not the crank side- because of the locating tang. you can just turn it 180 and re-seat it, obvioulsy.

After pressing down on the crank to try and get it to seat fully without checking for obstructions… Which was a dumb idea as it scratched the side of the bearing, but I didn't have time/money/patience to buy another bearing set- I cleaned it up. checked the new bearing after cleaning with a very good vernier, compared the total thickness around the whole bearing. it was dead nuts same as both the a trashed vg30 block bearing and the old vg33 bearing that came out of the motors that i had apart. So my theory was that it didn't damage it at all, and it was just the flash coating that was removed. I would compare to another bearing before running out to buy a whole new set.


clean it up with some 0000 steel wool with very LIGHT brushing or a scotchbrite pad or whatever you can to make the coating uniform. This will allow you to recheck where it's making contact since you will have a clean bearing to use as a visual.

also, make extra sure that the 1st bearing pair is wider than the middle two.

lastly, the bearing clearance that is required by the FSM or by block numbering does not change the fitment of the bearings when being pressed in by hand. Infact, it is barely even noticeable when you spin the crank over by hand with oil on the crank pins. That does not mean it's the proper clearance, it just means that the clearance is so fine that spinning it over is SOMETIMES not a clear indicator of whether you have the right bearing installed. It can be VERY deceiving. The bearings all start out at the same size, and they're put into a jig that bores them clean much like a cylinder hone, to the correct size. So inner diameter fitment will change in this case… outer diameter- which is your issue here, will not. regardless of bearing grading.