Rear main bearing fitment issue, photos.

  • Careless
    Careless
    Senior Member
    • 13279

    #16
    and for got sakes, use some vinyl hose from home depot for 50 cents a foot for your rod stud guidance when installing the crank. those packaging foam tubes you have are not going to protect a damn thing. they'll just move out of the way gracefully.

    I'm trying not to be nitpicky here.. but you can never have a block that is spotless. you just do the best you can. and I can see by the amount of oil and goo and shmoo in your main web registers, you haven't done the best you can. That stuff DOES change your clearance ever so slightly. You gotta be sure that all level surfaces are level and CLEAN.

    don't dick around on that detail.
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #17
    I never dick around on the detail in those situations where i know exactly what i'm doing.
    This just happens not to be one of those situations. But with y'alls knowledge, i'm confident
    i wont fuck it up. Again, thanks for the help.
    I opened it up with the mindset of "I'll just do this and this and this, button it up and i'm done.."

    Yeah…right. I should open a worm farm in the garage with all the cans of 'em i have open.

    Those foam sleeves are Nerf darts that my son unknowingly donated. I forgot to bring home some tubing from work.


    84 AE/Shiro #683/Shiro #820/84 Turbo
  • Careless
    Careless
    Senior Member
    • 13279

    #18
    Well, regardless of what the situation is, you can spray brake clean in there if you don't want to clean the entire thing- and use a clean piece of paper to clean right in the edges there.

    From now on, just think of it like this:

    If it's flat or it's a machined surface. make sure it's clean because it was machined to have something placed against it, and that means there isn't supposed to be anything in between those two things.

    knaw'mean?


    To do a proper aftermarket bearing purchase/selection while referring to the numbers used in the nissan grading system, your bearings all need to ADD UP to the same number across the entire bearing package.
    This involves math that you do not need to do with Nissan bearing shells since you can buy them individually per journal/crank pin. The reason for this is because you have to buy an entire bearing package that FALLS WITHIN the nissan range, and when you buy prepackaged sets, you cannot interchange the oversize amount per journal/crank pin. They are all oversized to the same ID in the aftermarket world…

    if you have a crank that is 0000, and block that is 3333, you have two options:
    A) buy a #3 set of nissan bearings
    B) find the CLEARANCE DIFFERENCE in size from the Standard 0000/0000 set to the #3 set of nissan bearings, then find the OVERSIZE bearing kit from an aftermarket manufacturer that will put the bearings into the range that the #3 set calls for.

    if you have a crank that is 1112, and block that is 2222, you have two options:

    A) buy a #3, #3, #3, #4 set of nissan bearings for each respective main/crank pin.
    B) find the largest clearance on the crank, and have the crank ground on all pins to match that of the largest clearance. Then buy an aftermarket kit that is even across the board, since your crank will be ground even now (and re-stamp your crank with indicators for yourself in the future). In this case, you'll have to have the crank re-nitrided as well.



    So when people think that Nissan bearings are too expensive- well… you better know what you're lookin' at
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #19
    The cost isn't too far from what i paid for the Sealed Power set. Purchasing the individual bearings (in my case they're all #3)
    through Courtesy runs 43.54 +12.00 shipping, But they're out of stock too.
    I'm kinda curious to know, what does a #3 bearing set translate into as far as a +/- offset in reference to a STD set.

    I'm still going to borrow a set of calipers from work and do the measurements and plastigauge is also easy enough too.

    I mean even Nissan sells a "set" 12208-02P00, US= 0.25 (I guess that would be a 0.25mm positive offset?)



    84 AE/Shiro #683/Shiro #820/84 Turbo
  • Careless
    Careless
    Senior Member
    • 13279

    #20
    Z_Karma;318200 wrote: The cost isn't too far from what i paid for the Sealed Power set. Purchasing the individual bearings (in my case they're all #3)
    through Courtesy runs 43.54 +12.00 shipping, But they're out of stock too.
    I'm kinda curious to know, what does a #3 bearing set translate into as far as a +/- offset in reference to a STD set.
    this is what i meant by you having to do math to select an aftermarket set that is as close to the summed up clearances in the FSM (i think some versions have the clearance numbers, some later ones do not).
    And you don't have to buy from courtesy. just go to your nissan dealership and order them.


    Z_Karma;318200 wrote:
    I'm still going to borrow a set of calipers from work and do the measurements and plastigauge is also easy enough too.

    I mean even Nissan sells a "set" 12208-02P00, US= 0.25 (I guess that would be a 0.25mm positive offset?)
    it should actually be 0.025mm undersized (smaller ID). I can't remember the range to be honest- I think its 0.025mm.
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #21
    Well slap me with a FSM and call me nancy…
    The bearing specs i was looking for are right on page EM-52.


    I hauled my crankshaft into work today so i can use our micrometer set, unfortunately
    we don't have a inside micrometer set. I'll take home my mitutoyo digi calipers.

    The Nissan grade 3 bearings are .0720-.0722.
    Clevite Standard are .0720

    This has been a learning experience, that's for sure.


    84 AE/Shiro #683/Shiro #820/84 Turbo
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #22
    To illustrate the main issue i was having with the aftermarket rear bearing:


    This was done with some cheap Harbor Freight digi calipers (est. +/-0.0005 error) but after a few repeated measurements (ends and middle) it's pretty
    obvious that the Sealed Power rear bearing inner dimension is too narrow.


    84 AE/Shiro #683/Shiro #820/84 Turbo
  • Careless
    Careless
    Senior Member
    • 13279

    #23
    good find. i would take this picture to where you bought them, and ask for a refund. bring bearings and caliper.

    regarding the FSM clearances… what did you come up with? is the standard bearing the one you need?
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #24
    I measured the main & crankpin journals at work but forgot to bring my good calipers home.
    The measurements were consistent, but i cant remember what they were now. I wrote them down though.


    84 AE/Shiro #683/Shiro #820/84 Turbo
  • Careless
    Careless
    Senior Member
    • 13279

    #25
    Z_Karma;318456 wrote: I measured the main & crankpin journals at work but forgot to bring my good calipers home.
    The measurements were consistent, but i cant remember what they were now. I wrote them down though.
    FWIW, I used Infiniti J30 VG30DETT bearings for both the rod and mains in ACL Race Flavour.

    If you'ze feelin' fancy, you can open an account online with Calico Coatings and Buy their CT-1 coated bearings in VG30DETT, and they send you a nice christmas card and you can get a nice black denim hat.
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #26
    Nah, i have too many hats as it is.

    My measurements indicate that a STD 0.0720 bearing (Grade2/3) would be within tolerance.

    " Block Crank Δ Δ/2 Bearing std. Clearance Limit
    Front 2.6265 2.4780 .1485 .07425 .0720 .0011 -.0022 .0035
    Pos 1 2.6260 2.4780 .1480 .074 .0720 .0011 -.0022 .0035
    Pos 2 2.6260 2.4770 .1490 .0745 .0720 .0011 -.0022 .0035
    Rear 2.6260 2.4770 .1490 .0745 .0720 .0011 -.0022 .0035








    The bearings i removed were ~.0710.

    I ordered a set of ACL 4M2777 STD. They should be here next week thru Amazon.
    Clevite MS-1951P are priced about the same on Ebay.
    That's about right, most of my weekend projects take about 3 weeks. :-P


    84 AE/Shiro #683/Shiro #820/84 Turbo
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #27
    Just arrived in the mail…ahhh much better. Measured with a better set of calipers than in the previous measurement comparison image.



    Maybe i can finally begin assembling things.


    84 AE/Shiro #683/Shiro #820/84 Turbo
  • Careless
    Careless
    Senior Member
    • 13279

    #28
    ACL race is what i useded. i likes them. good jorb.

    so it can go back together now?
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #29
    Yeah, I can has engine.


    84 AE/Shiro #683/Shiro #820/84 Turbo