Announcement

Collapse
No announcement yet.

somethings not right here

Collapse
X
Collapse
Who has read this thread:
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • somethings not right here

    so while rebuilding my engine just a rering/hone/headgasket job i put my pistons back in and the bearing caps on 6 and 7 wont go on, upon further inspection my rods were put on the piston head backwards. i know this because the caps have a squared edge that faces outward and the caps only go on one way, also the piston head has a notch that faces the front of the engine. so question is can i replace the rod without having to do work to the crank? the crank i measured everything out and it was in great condition also my original cross hatching was still there.

    What i dont want to do is put this thing together the wrong way again, it would feel wrong driving it. Also is the length of a rod backwards create the same amount of stroke? if not that could explain why my truck has always felt like it had a little more fire in its ass but just needed a good kick in the pants to get it out.

    any help would be appreciated, ive never put wrist pins in so i think ill take it to my neighbor or someone who knows what they are doing.
    91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
    85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
    00 Tahoe Z71........Stock
    97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

  • #2
    Originally posted by TylerT/AZ28 View Post
    so while rebuilding my engine just a rering/hone/headgasket job i put my pistons back in and the bearing caps on 6 and 7 wont go on, upon further inspection my rods were put on the piston head backwards. i know this because the caps have a squared edge that faces outward and the caps only go on one way, also the piston head has a notch that faces the front of the engine. so question is can i replace the rod without having to do work to the crank? the crank i measured everything out and it was in great condition also my original cross hatching was still there.

    What i dont want to do is put this thing together the wrong way again, it would feel wrong driving it. Also is the length of a rod backwards create the same amount of stroke? if not that could explain why my truck has always felt like it had a little more fire in its ass but just needed a good kick in the pants to get it out.

    any help would be appreciated, ive never put wrist pins in so i think ill take it to my neighbor or someone who knows what they are doing.
    make sure you do this right the first time, dont put them in like they are now take them back to who ever hung them and have them rehung and no charge to you. is the are not press fit then there should be either a wire lock or a flat style spirol lock on both sides of the pistone pins. remover 1 flip the rod and then reinstall. btw good eye and attention to detail. iv seen people pass right by stuff like this.

    Comment


    • #3
      are pistons 6 and 7 in the right spots? can you swap cylinders?

      Comment


      • #4
        Originally posted by 1BADAIR View Post
        are pistons 6 and 7 in the right spots? can you swap cylinders?
        x2 good point,i didnt think obout that.

        Comment


        • #5
          they are in the right spot, i took one piston out at a time and marked them for ease of reassembly. the engine was rebuilt by jasper 40 something thousand ago they wont redo it.
          they are press fit in there so ill have to find someone to do that for me because im sure not going to.

          if i switch 6 and 7 will there be some difference in wear? can i get away with doing that even though thats not where they came from?

          thanks for the attention to detail comment, i noticed it because the cap wouldnt st on there at all unless you put it on backwards then im looking around and all the squared edges are facing outward except that one and number 7
          91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
          85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
          00 Tahoe Z71........Stock
          97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

          Comment


          • #6
            Good catch, I should have asked that before I made you think you had some rods that might need reconditioning

            I'd swap 6 & 7. The big thing is to make sure that the cap goes with the correct rod. Stamp the cap rods with the correct cylinder number

            1998 Camaro Z28 - Bright Red, 6.0 TR224, 4l60e, 3.42 Eaton TrueTrac
            1989 Camaro IROC-Z Convertible - 355 big tube TPI, WC T5, 3.42 Zexel Torsen, CTS-V/C4 brakes
            1955 Bel Air 2 Door Post - 357 TPI, Muncie M20, 4 wheel disc

            2006 Saab 9-7x 5.3i Daily Driver

            Comment


            • #7
              i had my nieghbor measure them out to check if they were straight, i trust his work and they were true by him. one question i know mikes ls1 had the rods incorrectly placed and it made a huge difference, but does it make a difference in a sbc. i was under the impression that all the rods had to have the caps on a certain way so if this isnt the case then im just going to put them on and go with it.

              i just dont want to half ass it and while im driving be worried about throwing a bearing or something because or something i didnt fix while i was at it, i mean i took the time to analyze it so why not do it right
              91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
              85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
              00 Tahoe Z71........Stock
              97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

              Comment


              • #8
                Piston and rod cannot be installed backwards or there will be issues with the engine.

                Comment


                • #9
                  allright so in other words i definitely need to take the wrist pin out and flip the rod get a new wrist pin and press that back in
                  91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
                  85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
                  00 Tahoe Z71........Stock
                  97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

                  Comment


                  • #10
                    also do i have to replace wrist pins or do i reuse the same 2 that i took out?
                    91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
                    85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
                    00 Tahoe Z71........Stock
                    97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

                    Comment


                    • #11
                      I'd just swap 6 and 7, call it day. I'd guess that the assembly wasn't balanced and with new bearings there won't be a wear pattern.

                      1998 Camaro Z28 - Bright Red, 6.0 TR224, 4l60e, 3.42 Eaton TrueTrac
                      1989 Camaro IROC-Z Convertible - 355 big tube TPI, WC T5, 3.42 Zexel Torsen, CTS-V/C4 brakes
                      1955 Bel Air 2 Door Post - 357 TPI, Muncie M20, 4 wheel disc

                      2006 Saab 9-7x 5.3i Daily Driver

                      Comment


                      • #12
                        alrrighty i was gonna say just clock them but then the notch wont face towards the front of the engine, swapping them fixes just about everything. thanks guys ill let you know how it goes. might try to find another lt1 cam while im at it, i miss that cam
                        91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
                        85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
                        00 Tahoe Z71........Stock
                        97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

                        Comment


                        • #13
                          if i ever meet the person who built this engine they will come to their death. switching them didnt help. somehow my rods are offset which i never thought was possible of a 350 even with it slid all the way towards one end of the wrist pin it doesnt come out, also i figured out why my bearings were so worn off when i took then out of the engine, my crank has some decent sized gashes in it. so can i shove a 383 crank in there withough machining the block if not necessary? if so where can i get one, and ill probably need two wrist pins
                          91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
                          85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
                          00 Tahoe Z71........Stock
                          97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

                          Comment


                          • #14
                            will need diff rods with a stoker crank

                            Comment


                            • #15
                              well from the looks of it you can only buy a whole kit
                              91 Trans am, 305, Lt1 cam, 24lb injectors, headers, SLP LM2, SW chassis, massive panhard, lowered, modded TPI, Tuned, 4.10s, Lincoln locked
                              85 Z28 406/th400?/3.42 4th gen disc rear/4th gen dash
                              00 Tahoe Z71........Stock
                              97 K1500 lt4 cam, 1.6s, MPFI, Solid axled, IROKs,------winter beater

                              Comment

                              Working...
                              X