Author Topic: special tool 112150 (Read 4120 times)

wodcutr · « **on:** May 12, 2009, 09:51:22 AM »

Hey does anybody have this tool that is willing to loan it out or tell me of another way to loosen the crank bolt on an M42? I need to do a timing chain replacement and didn't want to have to buy all the special tools. Thanks!

B318M42W · « **Reply #1 on:** May 12, 2009, 10:45:48 AM »

you need an 8mm X 45 (min or longer) solid bolt / drill bit to lock the flywheel in place and use 2 crossed wrenches clamped with a vise grip to hold the camshafts together. I know it sounds bad, but it works just fine. pictures of the set-up are a bit lower http://www.m42club.com/forums/showthread.php?t=7517

wodcutr · « **Reply #2 on:** May 12, 2009, 06:54:17 PM »

I knew about the cam holding method and about putting the 8mm wheel lug aligner in place to hold the flywheel, but does doing that hold everything in place in order to loosen the crank bolt? The bentley says to loosen the crank bolt first and then put the cam tool and flywheel tool in place after getting to TDC. Maybe that is why you bent your bolt!

B318M42W · « **Reply #3 on:** May 12, 2009, 07:49:58 PM »

loll first it was a cheap bolt... take a good strong one. and also, use 2 bolts instead of 1! use 1 to loosen the crankshaft (but still keep some tension in it so that if you have to rotate the engine, you will be able) and then swap the flywheel bolts for the TDC (since the initial hard torque is done, the risk of bending the TDC one is about slim to none)
have fun with the job! it was a fun job to do. (seriously)

oh and there is also another alternative... I beleive that they guy took out his stock airbox, replaced it with a wood block, and then put a long lever-arm onto the crank bolt and then engaged the starter a few times to "break" the bolt.

Loosen the crankshaft bolt (22mm). It is VERY tight - ~230 ftlbs, but needs a shock to release it. Forget a rattle gun (not strong enough) or a breaker bar (you will slip the clutch first). So, remove the airbox (2 off 10mm nuts and a jubilee clip). Put a power bar (of suitable length) vertically upwards on the pulley bolt and a block of wood on the LH chassis arm. Crank the starter motor momentarily so that the bar rotates 90 degrees into the block of wood! 3-4 goes at this will usually release the bolt. It is a normal right-hand thread. Note that BMW uses a tool which bolts on in place of the vibration damper (6 bolts). The tool is locked against the chassis arm and a breaker bar is then used
from: http://www.esatclear.ie/~bpurcell/318istimingchain.html

wodcutr · « **Reply #4 on:** May 12, 2009, 08:58:50 PM »

Thank you for your information. It really helps when you talk to someone that has actually done it before. This is all very good stuff. I will get the parts ordered and see how this turns out. Is there any oil seals that I should address while I'm in there? It really has a bad leak and I don't know if it is the cover gaskets or something else.

B318M42W · « **Reply #5 on:** May 13, 2009, 12:05:28 AM »

a good "while you're in there" is the front crankshaft oil seal. oh if your water pump is getting old, it's a good idea to change it at the same time. I know that sometimes the oil filter gaskets sometimes leak. just clean up the front of the engine BEFORE taking it ALL apart. once it's all back together after the job, it will be easier to spot if the oil leak is still there.

oh and if you have A/C, you will have to take out the compressor bracket before removing the lower timing case. (IIRC 8 more bolts)

wodcutr · « **Reply #6 on:** May 13, 2009, 08:27:31 AM »

this is sounding more and more like a PITA. I guess it is still better than paying someone else to do it or worse ruining the motor because the chain breaks!