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    M42 timing problem

    I recently swapped out my timing case profile gasket and the headgasket. (the head was fine as was the head gasket). I have the head back on the block and torqued down properly. When I went to put my timing gears back on they didn't quite line up right with the cams. (I used a small prick punch to make mark on the cam and the gear. so i wiggled the cams a bit to align right. Then I turned the engine over to make sure valves weren't meeting pistons. I got about to where the crank TDC mark is closet to the ground.(half a rotation of the crankshaft) and I got a little binding so I backed off a bit but it didn't want to turn back to crank TDC. I tried to adjust the cams and crank but it didn't seem to help much and it till wants to bind on the way back to TDC. Whats the bet way to try and fix my timing issues? http://www.bimmerfest.com/forums/sho...d.php?t=443336
    I was following this guide to swap my tcpg and headgasket.

    #2
    are the plugs in,,,if they are maybe your just fighting compression
    double check all your marks, if its all where it was when it came apart it should be good to go
    but I would defin turn it over a few times, wiht plugs out and check the timing marks again and again

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      #3
      Plugs are out. the marks on the cam/cam gear line up but the crank isn't at TDC anymore so no reference point there. cams are also not at TDC as crank and cams were turning together when I was checking for interference.

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        #4
        http://imgur.com/a/axAG3 Here are some pictures of where the timing is at right now. Any help or advice is appreciated.

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          #5
          Your timing is off
          Originally posted by bmwm42
          PNW vulture pm me for parts
          Strategic nw e30 command

          Comment


            #6
            Yeah I figured that part out... Whats the best way to fix it? swap another m42?

            Comment


              #7
              Remove cam gears and lock flywheel at TDC moving the chain along slowly. Lock cams also per specs and then add gears and chain back. Key is using the correct or somewhat homemade tool to lock both. The flywheel lock is not expensive and a drill bit the right size will work.
              Alex 88 m5 | 91 318is | 19 Subaru Ascent
              BMW Tool Rentals & Fender Roller

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                #8
                Get the crank at TDC by measuring the distance between the piston crowns of piston 1 and 2. Piston 1 should be 81mm higher than piston 2 at TDC (= stroke length). I have measured this with a welding rod, sharpie and some calipers.

                The cams look off too. The lobes for cylinder 1 (frontmost) should be facing "up and in" at TDC, and the bolts are supposed to be centered in the sprocket slots. The gears might be off by a tooth. Make SURE to get them aligned with the driver's side of the chain pulled tight.

                Transaction Feedback: LINK

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                  #9
                  Originally posted by monty23psk View Post
                  Remove cam gears and lock flywheel at TDC moving the chain along slowly. Lock cams also per specs and then add gears and chain back. Key is using the correct or somewhat homemade tool to lock both. The flywheel lock is not expensive and a drill bit the right size will work.
                  I can't rotate the crank far enough to lock it at tdc without hitting a valve when cams are locked.

                  Comment


                    #10
                    Alright I got the crank shaft back at TDC (what a pain). The cam gear arrows point up with the head. I should have the cam gear bolts in the centers of the elongated holes correct? also can someone explain or show a picture of how the rear squares on the cam should line up with a straight edge? Thanks for all the advice. Sorry That I can't explain this stuff well. My phone is charging but I will upload some pictures of where the timing is at now.

                    Comment


                      #11
                      http://imgur.com/a/y8Suq Here are the pictures I took of where my timing is at right now. can anyone confirm this looks correct? Thanks again everyone.

                      Comment


                        #12
                        http://www.esatclear.ie/~bpurcell/318istimingchain.html reference this guide
                        Originally posted by bmwm42
                        PNW vulture pm me for parts
                        Strategic nw e30 command

                        Comment


                          #13
                          Originally posted by SedanSandwich View Post
                          http://imgur.com/a/y8Suq Here are the pictures I took of where my timing is at right now. can anyone confirm this looks correct? Thanks again everyone.
                          Cam timing looks okay from what I can see, crank timing is uncertain from the pics, but if the arrow and dot align you ought to be good. Of course the old screwdriver in spark plug hole one to show that you are in fact at TDC 1 is helpful. That, and the rotation by hand to double, then triple check valve clearance.

                          You seem to have this sorted.

                          Comment


                            #14
                            Originally posted by bmwm42 View Post
                            Thanks for the guide. the picture of the pencil across the back cam squares really helped me understand what it should look like.

                            Comment


                              #15
                              This is so easy.

                              1. Drop a 12" 3/8" drive extension in hole #1, rotate crank until the end of the extension is at it's highest point, insert lock tool from trunk tool kit through the hole in the block under the starter and into the dimple in the flywheel.

                              2. Rotate cams so that #1 lobes are pointing up at each other at a 45 degree angle and the squares at the very back of the cams are square with each other and the valve cover mating surface of the head.

                              Done.

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