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    Crank bolt removal

    Just picked up a 318is over the summer and was looking to replace the timing chain gaskets which seem to be leaking quite a bit and the thermostat and water pump. The only thing that worries me is getting the crank bolt off to remove the lower timing chain cover.

    I was wondering if I can use the flywheel locking tool to pin the flywheel and then remove the bolt or if I NEED the crank pulley securing tool. Some threads mention that using the flywheel locking method could warp the flywheel, but I have also read of others using this method exclusively.

    I'm not interested in using the starter to crank a breaker bar on a block of wood since this just sounds like a disaster waiting to happen! I also have a 1/2 impact wrench that I want to try out.

    Going to follow this guide, minus the timing chain guide replacement (this will have to wait till later)


    Flywheel locking pin


    Any tips are appreciated!
    Thanks in advance!

    #2
    I drilled a steel plate with a hole pattern that matches the 6 holes that hold the accessory pullies. It can then rest against a block of wood on the frame and you can go to town with a breaker bar (with a 1 meter pipe added on to the end lol). The hard part is the big hole in the middle to clear the crank bolt. In my case I had access to a milling machine, but you could probably do it with a series of holes and then cutting the remainder out to clear the big bolt. I don't think that using the flywheel locking pin is a hot idea. As for the starter trick, I have used it a couple of times, but you are still left with the issue of putting the bolt back at the proper torque. Impact guns are also a bad idea in my opinion, and you will probably want to replace the crank bolt if you use that method (and that obviously means that you should not use the gun to install the bolt).

    The RIGHT way is to make or borrow the crank locking tool, and that is my suggestion to you.

    Transaction Feedback: LINK

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      #3
      ^ just go rent it and do the job right without worrying or stressing - My suggestion

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        #4
        Given how tight that bolt is in there, rent or make the tool. If you didn't shear the flywheel
        lock outright, that amount of stress against the bellhousing and down the crank and
        on its bearings would make me really uncomfortable.

        I had 2 4' bars, and it probably took 200 lbs at the end to break that bolt loose....

        t
        now, sometimes I just mess with people. It's more entertaining that way. george graves

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          #5
          Thanks for the definitive responses, this makes the process much easier and hopefully will avoid wreaking anything down the line.

          I will probably end up buying the tools from Pelican Parts since I can get both for about $115, which is expensive but not bad since I plan on holding onto the 318is for a while, are there any cheaper places around?

          I would rent them, but I don't know of any places in Canada which rent these tools, or can they be rented from a dealer?

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            #6
            I just used an impact gun. Not the correct method, but the bolt is huge and it's not going to be hurt by much.

            The part that was a pain in the ass for me wasn't the crank bolt, it was getting the thermostat housing bolts out. Depending on the condition of your engine, the bolts might be slightly corroded and not want to come out. They're also very delicate, and take very little torque. Remember that they're going into an aluminum head, so it's easy to strip out or cross thread. I actually ended up sheering a bolt head clean off using a puny 1/4 inch ratchet and almost no force. I ended up having to weld directly the nub to get the bolt out, and drilling and tapping another hole to a bigger size because the previous owner cross threaded it.

            All I can say is go really slowly, make sure you look up the correct torque values, and make sure you use antiseize on anything going back into the aluminum head.

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              #7
              Yeah, I recommend keeping an M6x1 helicoil kit handy. In particular, the top bolt on the main guide rail tends to strip the threads in the head (driver's side on LHD cars). If you replace that guide, make sure that you have a 45mm M6 bolt, not the old 40mm one!

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                #8
                Btw, it never hurts to have too much reading material. Here's another writeup that I used that might help you out.

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                  #9
                  Originally posted by Rainydays View Post
                  Btw, it never hurts to have too much reading material. Here's another writeup that I used that might help you out.

                  http://www.esatclear.ie/~bpurcell/318istimingchain.html
                  There is so much to read out there that I remember this one but couldn't find it again. Thanks for posting!

                  I definitely need to pick up a helicoil set, I replaced my valve cover gasket and had no issues, but you never know what the next bolt has coming for you.

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                    #10
                    If you have the pan off throw some 2x4s under the crankshaft counterweights. This will keep the crankshaft from turning and allow you to take the "Jesus Nut" off. Works for me every time an you don't need to buy some crank holding tool.

                    The Build:
                    http://www.r3vlimited.com/board/showthread.php?t=191125

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                      #11
                      Originally posted by ttrousdell View Post
                      If you have the pan off throw some 2x4s under the crankshaft counterweights. This will keep the crankshaft from turning and allow you to take the "Jesus Nut" off. Works for me every time an you don't need to buy some crank holding tool.
                      I have heard of this method being effective as well, but it also scares me, although it would probably work!

                      The right tools all the way it seams!

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                        #12
                        I bought the SIR tool from Pelican to loosen the crank bolt on my m42 too. In addition to the tool, make sure you have a rock-solid breaker bar and big-ass cheater bar before attempting this. Don't cheap out. My 3/4-inch drive, 40-inch Tekton breaker bar broke (metal drive sheared) when I put 4-ft cheater bar over it and tried (without success) to loosen the bolt.

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                          #13
                          Double check where your oil leak is coming from. It's usually the gasket behind the lower assembly and not from the timing cover. That gasket is way more involved...

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                            #14
                            Breaker bar + starter bump = done. Use a hammer on the end of the breaker bar to reinstall.

                            But the correctest way is to take it to Germany and have a german mechanic use the german tools with dials and gauges or else the world will explode.
                            Originally posted by Andy.B
                            Whenever I am about to make a particularly questionable decision regarding a worryingly cheap diy solution, I just ask myself, "What would Ether-D do?"
                            1987 325iS m30b34 Muscle car (Engine electrical phase)
                            ~~~~~~~~~~
                            I was born on 3/25…
                            ~~~~~~~~~~

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                              #15
                              Mine wouldn't budge using the starter bump method, I had to heat the bolt up with a torch, then it came right out, first bump.

                              IG @turbovarg
                              '91 318is, M20 turbo
                              [CoTM: 4-18]
                              '94 525iT slicktop, M50B30 + S362SX-E, 600WHP DD or bust
                              - updated 3-17

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