cam bearings don,t fit?

Discussion in 'Blocks' started by Grumpy, May 15, 2015.

  1. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

    http://www.jegs.com/i/JEGS-Performance-Products/555/25405/10002/-1
    http://garage.grumpysperformance.com/index.php?threads/cam-bearing-install-tools-install-info.1479/
    VERIFY,SOME DART AFTERMARKET BLOCKS DON.T USE OEM CAM BEARINGS
    http://www.speedwaymotors.com/Dart-DT-1T-Cam-Bearings-for-Little-M-Chevy-Block-Set-5,24164.html

    http://www.lislecorp.com/uploads/instru ... 726DB5.pdf

    the tool Ive had and used for DECADES, it works reasonably well.
    but check around for a used one in good condition, I bought mine at a chevy swap meet for $80


    http://garage.grumpysperformance.com/index.php?threads/engine-block-cylinder-wall-thickness.976/

    http://www.lislecorp.com/divisions/products/?product=58
    http://www.lislecorp.com/uploads/instructions/18000_WebInstr_CC56DD9726DB5.pdf

    http://www.kmjent.com/cart/product.php?productid=597 (good value)

    http://www.dura-bondbearing.com/Portals ... lletin.pdf

    http://www.pbw-india.com/theory.htm

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    MAIN BEARINGS FEED FROM THE CAM BEARINGS SO LINING UP OIL FEED HOLES IS CRITICAL
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    most blocks only have the outer or end cam bearing journals grooved under the cam bearings making proper indexing of the oil feed holes on the 3 inner cam bearings critical, some blocks don,t even have those outer block cam bearing locations grooved
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    any time you go to install new cam bearings in an engine you first take detailed notes and a few pictures of the OLD cam bearing in the block under good lighting to note the location of the oil feed holes and and grooves, then as they are removed you number them each as its removed and measure them as on many engine they are NOT INTERCHANGEABLE between all main cap locations
    chevy cam bearings are NOT all interchangeable, youll want to pay attention to the oil feed holes and the DIFFERENT diameters of the bearings, and ideally have the proper tools.
    different BRANDS of bearings seem to have different tolerances, diam. and widths and some are tapered on one edge to make installation easier.
    cam bearing tools also vary a great deal in how easily they can install and remove bearings, and the machining on blocks varies
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    USE YOUR PLASTIGAUGE AND PRECISSION MEASSURING TOOLS , MEASSURE CLEARANCES AND BE SURE YOUR NOT BINDING< ANYPLACE
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    this cam buttons correctly installed but the retainer plate tabs have not been bent up to lock the bolt heads from rotating
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    Last edited: Jul 24, 2017
  2. Unforgiven

    Unforgiven Well-Known Member

    OK now I am confused.. The cam bearings in my sbc were lined up with the oil holes in my block. I am reading now that the holes in the cam bearing are suppose to be in the 10:00 and 2:00 for the front bearing, and #2-5 bearings should be in the 2:00 position. This is suppose to create an oil wedge.
    This information is in conflict with the information given above, where it states the cam bearings must line up with the oil holes.
    Now I notice that there is no groove in the block or on the back of the bearing for #'s 2-4.

    So how does the oil get into the bearing if it is installed in the 2:00 position?

     
  3. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

    different blocks and bearing locations have slightly different configs,
    obviously if theres no oil feed groove under the bearing the oil feed holes must align with the oil feed passages,
    with the block in the upright position the cam bearings are fed,
    from the upper central cam, or lifter gallery oil passage, look at the diagrams
    most cam bearings come with instructions and diagrams.
    and yeah it generally helps to look at the old cam bearings and oil feed hole locations, take notes and in most cases re-install the new bearings in a similar fashion.
    chevy V8 cam bearings are NOT universally interchangeable between locations

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    MAIN BEARINGS FEED FROM THE CAM BEARINGS SO LINING UP OIL FEED HOLES IS CRITICAL
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    carefully measure the old cam bearings and pay attention to oil feed hole locations
    the bearings are not universally interchangeable and yes size varied

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    Last edited: Mar 15, 2019 at 8:29 AM
  4. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Grumpy has listed correct for SBC.
     
  5. T-Test

    T-Test reliable source of info

    I always read the installation instructions first and if none find the answer before installing. JMTCW
     
  6. Unforgiven

    Unforgiven Well-Known Member

    Wow! Do I feel embarrassed now.
    After getting my block cleaned, I now see that there are grooves behind the cam bearings.:oops:
    Musta been filled with all the babbit that was missing from the rod and main bearings. :D
     
  7. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

  8. Indycars

    Indycars Administrator Staff Member

    You're in good company, everyone here has been in that club at one time or anther !
     
  9. T-Test

    T-Test reliable source of info

    Every day for me!! If I could REMEMBER half of what I use to know.
     

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