Announcement

Collapse
No announcement yet.

M42 Block Reconditioning

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

    M42 Block Reconditioning

    My #4 cylinder died (fouled plug, stuck open injector or a combo of the both), so I decided to just re-ring all of them and recondition the block a bit.

    I'm planning on buying a flex-hone (dingle-ball hone), and de-glazing the cylinder walls. I think the cross-hatching still looks pretty good, so it shouldn't need a machine shop hone. What do you guys think?


    #4 is the closest one to the camera. The little jagged line near the top of the bore isn't palpable at all... I'm not sure what it is.





    Again you can't feel that little line at all, so I'm thinking the flex hone will clean it all right up.


    Originally posted by Gruelius
    and i do not know what bugg brakes are.

    #2
    The hone will probably clean that up, might as well go up a size for the pistons.
    IG: deniso_nsi Leave me feedback here

    Comment


      #3
      Yes you need to hone the cylinders for the new rings to properly seat. I am using one of those flex ball hones.
      what you did to this car is like getting a supermodel naked and willing to do anything you please. now here you are faced with ths once in a lifetime opportunity and then you squander it by making her fuck you in the butt with a 24" strap on. you are a sad, silly little boy.

      Comment


        #4
        If the cross hatch was that clean in my block, I would measure for round and put it together, assuming it passes.

        Ken, I think your rings never seated.

        Luke

        Closing SOON!
        "LAST CHANCE FOR G.A.S." DEAL IS ON NOW

        Luke AT germanaudiospecialties DOT com or text 425-761-6450, or for quickest answers, call me at the shop 360-669-0398

        Thanks for 10 years of fun!

        Comment


          #5
          Originally posted by dude8383 View Post
          The hone will probably clean that up, might as well go up a size for the pistons.
          Up a size for the pistons? I'm assuming you mean bore it, and get larger pistons. Not doing that.
          Originally posted by Gruelius
          and i do not know what bugg brakes are.

          Comment


            #6
            Originally posted by twistednut View Post
            Yes you need to hone the cylinders for the new rings to properly seat. I am using one of those flex ball hones.
            PM sent
            Originally posted by Gruelius
            and i do not know what bugg brakes are.

            Comment


              #7
              Just an FYI, Honing and flex honing are 2 different operations. But to answer your question, a flex hone should clean up and even it doesn't is an inexpensive thing to try before having a machine shop rehone and/or bore and hone the block.

              Also make sure you order the right grit you need to achieve your desired finish.

              HTH,
              Ben
              Originally posted by BillBrasky
              E36's are the Stephen Baldwin of the 3 series family. They barely hold everything together and they only sold a lot because of the popularity of their older sibling.
              1991 318i Alpine II - S50/5-lug swapped - track car
              1989 325i Cirrusblau - Daily
              1970 2500 - Malaga over Grey Cloth
              2012 F350 6.7PSD

              Comment


                #8
                Originally posted by BenM View Post
                Just an FYI, Honing and flex honing are 2 different operations. But to answer your question, a flex hone should clean up and even it doesn't is an inexpensive thing to try before having a machine shop rehone and/or bore and hone the block.

                Also make sure you order the right grit you need to achieve your desired finish.

                HTH,


                Ben
                Any recommendation on the grit. I've seen 240 as a pretty common one.

                M42 stock Goetze brand rings aren't moly, are they?
                Originally posted by Gruelius
                and i do not know what bugg brakes are.

                Comment


                  #9
                  Originally posted by kencopperwheat View Post
                  Up a size for the pistons? I'm assuming you mean bore it, and get larger pistons. Not doing that.
                  correct me if i'm wrong, but shouldn't you go up one size if you hone the block? you'd have to go up a size so that the seal remains within spec. right?



                  i might be wrong, i've only built one motor
                  IG: deniso_nsi Leave me feedback here

                  Comment


                    #10
                    Originally posted by kencopperwheat View Post
                    Any recommendation on the grit. I've seen 240 as a pretty common one.

                    M42 stock Goetze brand rings aren't moly, are they?
                    Can't say I have experience with building engines so I can't say for sure, but it seems that 240 grit is relatively mild and I'd start with that. If that doesn't do it, I would lightly try 180 or even 120 if you're bold, but just be very careful if you are using an oversized flex hone. 240 should take the mark out after a few swipes.

                    I work with swaged and machined (slots, holes, grooves, etc.) aluminum tubes and we typically use flex hones to remove burrs that worn mills or drills can leave in the inside of the tube, at the bottom of particular slots or holes.


                    Originally posted by dude8383 View Post
                    correct me if i'm wrong, but shouldn't you go up one size if you hone the block? you'd have to go up a size so that the seal remains within spec. right?



                    i might be wrong, i've only built one motor
                    You'd have to be pretty damn aggressive to hone out a block +.25mm or about .010"! I mean it could be done, but typically you wouldn't take that much off. You would just bore it to .001-.002" less and then hone it to size.

                    Flex honing is completely different than honing.
                    Originally posted by BillBrasky
                    E36's are the Stephen Baldwin of the 3 series family. They barely hold everything together and they only sold a lot because of the popularity of their older sibling.
                    1991 318i Alpine II - S50/5-lug swapped - track car
                    1989 325i Cirrusblau - Daily
                    1970 2500 - Malaga over Grey Cloth
                    2012 F350 6.7PSD

                    Comment


                      #11
                      Originally posted by BenM View Post
                      You'd have to be pretty damn aggressive to hone out a block +.25mm or about .010"! I mean it could be done, but typically you wouldn't take that much off. You would just bore it to .001-.002" less and then hone it to size.

                      Flex honing is completely different than honing.
                      You're right, I'm a noober goober. Flex-honing is probably what Ken is going after.

                      Am I right that if one were to hone the cylinder bore, you'd have to go up a size?
                      IG: deniso_nsi Leave me feedback here

                      Comment


                        #12
                        Originally posted by dude8383 View Post
                        You're right, I'm a noober goober. Flex-honing is probably what Ken is going after.

                        Am I right that if one were to hone the cylinder bore, you'd have to go up a size?
                        Depending on just how out-of-round the bores are to begin with.

                        Old school BS rebuilds get "knurled" pistons, as when the grooves are cut, it makes the piston "larger" so it can fit the bore...for a few thousand miles if you are lucky.

                        Closing SOON!
                        "LAST CHANCE FOR G.A.S." DEAL IS ON NOW

                        Luke AT germanaudiospecialties DOT com or text 425-761-6450, or for quickest answers, call me at the shop 360-669-0398

                        Thanks for 10 years of fun!

                        Comment


                          #13
                          Just bought the 240grit flex-hone... I'll take pics for you guys. Thanks for the input.
                          Originally posted by Gruelius
                          and i do not know what bugg brakes are.

                          Comment


                            #14
                            yes knurled is old school, but it does work a bit
                            decent rings make a difference
                            out of round is a possible to happen

                            but sometimes you can just hone em, new rings and get many thousand out of a old engine

                            for a cylinder that ws done to 40 pounds pressure, the walls look pretty good,

                            honing stone will remove the top ridge better then "dingle-berries"

                            werent you geting the engine hot tanked ? wht did the machine shop think

                            Comment

                            Working...
                            X