Main Crank Pulley

[91318isguy]

Hi guys,

I'm in the middle of timing chain replacement and don't want to work hard the wrong way. Is the nut on the main crank pulley a reverse or standard threading nut? Also is the pulley tapered or a keyway pulley?

M42 for life.

Keith

[1991 E30 M42]

I don't remember if it is reverse threaded or not but i do remember it was very tight, I would have to say 200ft/lb +/-, and it has a keyway

[91318isguy]

How hard was it to pull it off? Still need to know if it's a reverse thread or not. Did you use a cheater bar? I've heard some guys recommending using an impact wrench.

[1991 E30 M42]

I used a harmonic balancer puller to take it off, I used my an impact wrench to remove it but that was only because the last time I removed one the engine was out and I didn't have a way to keep the crank from turning

[91318isguy]

Yeah, I've got the engine out of the car because I'm doing a swap to an engine that probably doesn't have the main bearing possibly damaged. So far I've found a heavy duty 8mm allen wrench is working pretty well holding the crank still I put it thru a hole in the bell housing into a notch in the fly wheel.

Is guibo or another engine guru to tell me if it's reverse thread or not please.

[flyinglizard]

Standard thread, with locktite.  Straight crank with key.

[91318isguy]

Thank you thank you thank you. How'd you pull your off... not that E30 M42 isn't good enough... just want to pick brains, that's all. Was the engine in or out of the car. Did you use a breaker/cheater bar or an impact wrench?

[flyinglizard]

Take out the rad, place breaker bar with extension, on bolt, hit starter. Wrap the bar with a towel. Leave the chain on the head !!.
 MM

[xaos.]

http://www.m42club.com/forums/showthread.php?t=10828   do not use loc tite!!! you will never get it back out!! the bolt will break if you use it!!!  it is a stretch bolt like cylinder heads, that is why it must be replaced when taken out. its 8 bucks from bma.  torque is 160fp to tighten. I use a block of wood most of the time to stop the breaker bar.  it may take a few trys with the starter  you got to go manually move it back to the breaker bar can pick up speed before stopping.   you dont need to take out radiator to do this either!!  22mm deepwell socket  is the crank bolt size  


when the motor is out of the car there is a hole under the intake where a screw driver or cam stops fit. there is a hole in the flywheel that it will slid in to and then you can crank away with a impact.  or use a flywheel tool and have someone hold it while you impact the shit out of it.   ive done it both ways a few times

standard thread!  again no loctite replace bolt! cant stress that enough!

[///m42 sport]

ehh, I reused my bolt. I was able to loosen the bolt with a breaker bar plus a extension ontop of the breaker bar...the longer the bar, the more torque generated with same amt of force.  

Have no problems so far.  But I didn't know the cranker bolt was disposable.

[RED IS 91]

ehh, I reused my bolt. I was able to loosen the bolt with a breaker bar plus a extension ontop of the breaker bar...the longer the bar, the more torque generated with same amt of force.  

Have no problems so far.  But I didn't know the cranker bolt was disposable.

Audi says the same about their bolt but I reused mine on two different cars with no issues. On the audi it was 150 ft lbs then 90 degrees more.

[flyinglizard]

It is green loctite on by BMW.   I use the blue low tension loctite, to put it back on. Just like the rest of the cars. Sorry for the misp[eak.  Do Not use red locktite for sure. red needs 400 degrees to come loose.
 MM

[rfbehn]

Unbolt the pulleys from the front and leave the main bolt alone.  Then hold the flange with a 24 inch channel lock and use a long breaker bar.