Results 1 to 5 of 5

Thread: 2.5L Crank shaft connecting rod journal sizes.

  1. #1
    Garrett booster
    Join Date
    Mar 2023
    Location
    Delhi, ON
    Posts
    64

    2.5L Crank shaft connecting rod journal sizes.

    So trying to order new bearings for this motor I am putting back together for my kid. Just going to give it a quick 600 grit polish.

    Connecting rod Journals measure 1.963".

    All data I'm seeing for bearings is showing a stock nominal size of 1.9687 max and 1.9677 min

    So by my calculations this is about 0.005 undersized. Or 0.127mm

    The only bearings I'm seeing on rock auto are .25, .5 or .75mm.


    What am I doing wrong?

    This engine shows no signs of ever being rebuilt.

    Its a 91 Common block 2.5 T1.

    There is a 10-1X mark on the bearings and cap side has B-7 rod side has A-8.


    If I can't figure this out it's just polish the journals with 600 grit and leather and toss the old bearings back in.

    Thanks for any insight.

  2. #2
    Garrett booster
    Join Date
    Mar 2023
    Location
    Delhi, ON
    Posts
    64

    Re: 2.5L Crank shaft connecting rod journal sizes.

    Markings on the bearings.

  3. #3
    Garrett booster
    Join Date
    Mar 2023
    Location
    Delhi, ON
    Posts
    64

    Re: 2.5L Crank shaft connecting rod journal sizes.

    So... I was still really curious about my findings... Remembered I have a different caliper newer/ potentially better.

    I also have a set of telescoping bore gauges.

    I double checked the crank journal measurements with that caliper and they are all 1.967 +/- 0.0005 so it would like like it's a Standard shaft that hasn't been ground.

    Then I torqued the rod bearing nuts bakc up and telescope gauge measures 1.969. So we'll within stock spec.

    Ill order a new set of standard CLEVITE 77's or tri metals.

  4. #4
    Super Moderator Turbo Mopar Staff 135sohc's Avatar
    Join Date
    Aug 2008
    Location
    SoMd
    Posts
    6,183

    Re: 2.5L Crank shaft connecting rod journal sizes.

    Years ago one could get .001 inch/.025 mm undersized bearings which were great for a typical 150 thousand mile engine that was not 'worn out' but just outside of the standard sizes after cleaning up any surface imperfections. Considerably less cost than going a full .010 under and left more 'meat on the bone' for next time if that was a concern. I guess most machine shops did not know they existed or would have rather sold a full .010 under grind and polish. So Clevite stopped making them.
    1994 Shadow Sedan. 2.2 N/A, A568 400,000 miles. "the science experiment"
    1987 Shelby CSX #418. Long term rebuild and restore ?

  5. #5
    Garrett booster
    Join Date
    Mar 2023
    Location
    Delhi, ON
    Posts
    64

    Re: 2.5L Crank shaft connecting rod journal sizes.

    Quote Originally Posted by 135sohc View Post
    Years ago one could get .001 inch/.025 mm undersized bearings which were great for a typical 150 thousand mile engine that was not 'worn out' but just outside of the standard sizes after cleaning up any surface imperfections. Considerably less cost than going a full .010 under and left more 'meat on the bone' for next time if that was a concern. I guess most machine shops did not know they existed or would have rather sold a full .010 under grind and polish. So Clevite stopped making them.
    Oh ya, hoping I can polish the little dings in the journals from the dingle ball hone. (never even thought to put a rubber cap on the end of it.)

    If we get another 50k km out of this engine I'm happy. That would take her like 5 years or more to put on.


    New bearings show up Monday.

    Going to 600 grit polish and then a try a quick leather strap polish and send it.

Similar Threads

  1. Crank journal
    By John B in forum Engine - Block, Piston, Heads, Intakes
    Replies: 11
    Last Post: 04-15-2011, 01:04 PM
  2. Engine Non CB Crank and Connecting rod
    By trbowgn in forum Parts Wanted
    Replies: 1
    Last Post: 02-08-2011, 02:24 PM
  3. Crank Journal OD measurements
    By bfarroo in forum Engine - Block, Piston, Heads, Intakes
    Replies: 2
    Last Post: 12-30-2010, 05:09 PM
  4. Crank journal diameters, To turn or not to turn
    By bfarroo in forum Engine - Block, Piston, Heads, Intakes
    Replies: 3
    Last Post: 06-12-2009, 09:31 PM
  5. Crank main and rod sizes??
    By FRAN_Astur in forum "I need help!"
    Replies: 12
    Last Post: 02-02-2009, 08:11 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •