M42 crank bolt removal

[cheesebox]

The guides I've read for 318is / M42 timing chain replacement suggest removing the crank bolt either by using the bmw pulley locking tool and a breaker bar, or cranking the engine over with a breaker bar on the bolt and cracking it against a piece of wood on the chassis arm. Apparently it's tightened to 230ft/lbs, so a simple spanner won't do.

Can anyone explain why just locking the flywheel and camshafts with the appropriate tools wouldn't be sufficient?

[MikeeMiracle]

heh....we did this the other day. Watch out for the huge bang once it comes loose. Be interested to know the answer to this myself if it has to be tightened to that torque, I thought it was just being stubborn.

[David318is]

get a bottom pulley from a scrapyard and weld a length of steel tube to it

Fit this in place of your existing pulley after locking the flywheel and jam a

wooden block between the bar and chassis rail then use a good 22mm

socket and long bar to get enough leverage to undo it. When tightening

up the new bolt do the same to stop the engine turning and just do it up

as tight as you can

[cheesebox]

Well, I unscrewed it last night using the starter motor, a breaker bar and a piece of wood. Worked on the third attempt.

David318is - like the idea for making a locking tool, would have preferred to do it that way rather than putting strain on the internals, read it too late unfortunately.

Still don't understand why locking the flywheel doesn't work - it seems you can still turn the engine over on the crankshaft pulley. Weird. Or is it? Maybe I've missed something fundamental here!

[keggy]

if u have a good compressor and impact gun it can be removed