Announcement

Collapse
No announcement yet.

1946 chief cylinder issues???

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 1946 chief cylinder issues???

    I have a 1946 Indian100_1787.jpg100_1788.jpg100_1789.jpg100_1790.jpg chief and in the process of changing the valve covers I discovered a ( minor, I hope ) issue with the rear cylinder ( picture ). As you can see the sleeve is a 1/4 inch shy of being at the top of the cylinder like the front cylinder is. ( picture ). I noticed in the front cylinder it looks like the top 1/4 inch of the sleeve might be a different piece of metal it is a gold color exactly a 1/4 inch.

    My questions are is this common for a 1/4 inch piece to be placed in the top part of the cylinders when sleeving?
    Is there a fix for the rear cylinder/sleeve?
    The piston rings do not appear to go higher than the sleeve in the rear cylinder so I am not sure how bad this issue is?

    Any suggestions or input would be appreciated.

    thanks
    jeff

  • #2
    Your pictures appear to show one cylinder with a sleeve, and one without. The 1/4 inch line is merely the top of ring travel. The gold color is heat and oil discoloration common to all engines. If the one cylinder is indeed sleeved and short, as long as the rings are not affected it won't bother a thing other than slightly dropping the compression on that cylinder.
    Last edited by Rubone; 11-26-2019, 11:30 PM.
    Robbie Knight Amca #2736

    Comment


    • #3
      The cylinder bores look to have enough scoring to to warrant further inspection.I would pull the cylinders and run hone thru a couple of passes and you will be able to get a better idea if you also need rings or pistons.
      Tom

      Comment


      • #4
        Originally posted by tfburke3 View Post
        I would pull the cylinders
        Agree. Liners can slip and you don't want a liner taking out your baffles, so you want to see if the liner is now down below the base of the cylinder.
        Pisten Bulley is Harry Roberts in Vermont.

        Comment


        • #5
          If a sleeve is loose enough to move, Jeff,..

          It isn't conducting the heat as it should.

          Over-size LA Sleeves ain't cheap, but maybe necessary.

          A thou and a half interference should hold it, but the finish of both the sleeve and bore must be as micro-fine as possible.

          ....Cotten
          PS: A base stress-plate for the final piston fit is prudent, too.
          Attached Files
          Last edited by T. Cotten; 11-27-2019, 01:04 PM.
          AMCA #776
          Dumpster Diver's Motto: Seek,... and Ye Shall Find!

          Comment


          • #6
            As, tfburke3, commented in post three; about the scouring of the cylinder wall in pic #4; I would be concerned with that too.

            In addition to your original question, I would be removing the cylinders and take a good look at what is going on. You have the heads off; no reason, not to go deeper.

            bjind

            Comment


            • #7
              Finally found a pic of the distortion, Folks,...

              That a stress-plate alleviates during the honing procedure.

              The shadow is where the wall is pulled outward directly 'above' the base stud,
              just as installation upon the cases will cause with larger over-bores.

              A sleeve distorts like a circular spring within a circular spring.

              ....Cotten
              Attached Files
              AMCA #776
              Dumpster Diver's Motto: Seek,... and Ye Shall Find!

              Comment


              • #8
                Originally posted by T. Cotten View Post
                Finally found a pic of the distortion, Folks,...

                That a stress-plate alleviates during the honing procedure.

                The shadow is where the wall is pulled outward directly 'above' the base stud,
                just as installation upon the cases will cause with larger over-bores.

                A sleeve distorts like a circular spring within a circular spring.

                ....Cotten
                Would surfacing the cylinder base and crankcase perfectly flat alleviate the need for torque plates? Understand the use of torque plates with aluminum cylinders where softer metal pulls under stress but wonder why 2 perfectly flat surface would not remain so when clamped togethet?

                Comment


                • #9
                  Originally posted by Bubbalowe View Post
                  Would surfacing the cylinder base and crankcase perfectly flat alleviate the need for torque plates? Understand the use of torque plates with aluminum cylinders where softer metal pulls under stress but wonder why 2 perfectly flat surface would not remain so when clamped togethet?
                  Certainly, Bubbalowe,...

                  Those surfaces should be inspected and corrected as necessary.

                  Fastener stress, however, occurs because all metal 'moves' under pressure. Even cast iron.
                  If it didn't, it would crack.

                  Torquing to spec upon a block simulates installation when honed straight, so it will return to straight when finally installed at that spec.
                  Commonly, a well-compressed gasket is used as well.

                  Its much worse with HDs.

                  ....Cotten
                  PS: Stress plates only become critical at large over-bores, or sleeved castings.
                  Or if you want that last ounce of performance, or longer motor life.

                  PPS: Ever wonder why Evos had 'through-bolts' instead of separate base and head fasteners?
                  And they lasted so much longer?
                  Last edited by T. Cotten; 11-28-2019, 06:16 PM.
                  AMCA #776
                  Dumpster Diver's Motto: Seek,... and Ye Shall Find!

                  Comment

                  Working...
                  X