Locking crankshaft, flywheel removed....How to?

[Dave M]

So the M50 is on an engine stand, flywheel removed and I'm planning on removing the head one evening this week (when I'm not skate skiing or drinking). Without too much investigation, it seems that the most common wy to ensure the crank does not move is to lock it via the tranny/flywheel, BMW tool 'bla bla bla'.

What , if any, is the best way to lock the crank without the tranny/flywheel installed?

Any advice appreciated, lots of pics to come when i get them off the camera,

Dave M

[Scott H]

is so that the pistons don't move up and down and hit the valves since they have been disconnected from each other. It takes more than the accidental bump to move the crank until the head comes off because there is still some compression in the cylinders.

So the M50 is on an engine stand, flywheel removed and I'm planning on removing the head one evening this week (when I'm not skate skiing or drinking). Without too much investigation, it seems that the most common wy to ensure the crank does not move is to lock it via the tranny/flywheel, BMW tool 'bla bla bla'.

What , if any, is the best way to lock the crank without the tranny/flywheel installed?

Any advice appreciated, lots of pics to come when i get them off the camera,

Dave M

[Tiger]

Get a steel flat bar at Home Depot... drill hole to match flywheel bolt mounting point... bolt it in and allow it to brace against the engine stand or drill another hole to match the tranny mount hole.

[632 Regal]

you could fill a cylinder with sand and that should stop the piston from moving up while you loosen the bolt.



sorry, saw this whan really young and had to spread the stupidity. I actually saw one dude use a nylon rope fed into the cylinder to accomplish the same task...neither look appealing enough to do myself.

[winfred]

that, or if you have the pan off jam the crank with a chunk of wood between a counter weight and the block

Get a steel flat bar at Home Depot... drill hole to match flywheel bolt mounting point... bolt it in and allow it to brace against the engine stand or drill another hole to match the tranny mount hole.

[Dave M]

that, or if you have the pan off jam the crank with a chunk of wood between a counter weight and the block

Thanks, while searching the archives i came across your block idea. Thought there may be a common way i wasn't aware of. I do think the block of wood suits me best

Another question if i may.

As I'm mating the head to another block, can I assume if the flywheel "OT" mark on the new block is lined up properly, the crank is in the right position? I assume when they (whom i bought it from) removed the head, they had it TDC.

Thanks,

Dave M

[winfred]

the #1 piston at tdc (all of the way up) will get you close enough if you don't have the ballencer on with it's ot mark, yet ot lined up with the mark on the timing cover is what you want

[Dave M]

I should have the balancer on before I plop the head on, so all should be good.

Tahnks again Winfred, more questions to come,

Dave M

[Bellicose Right Winger]

I think it's very unlikely seller went this trouble.
Now the question becomes how do you determine if M50 head is at TDC?
Check for "rocking" valves on cyl 6?

Paul Shovestul

....... I assume when they (whom i bought it from) removed the head, they had it TDC.

Thanks,

Dave M

[Bellicose Right Winger]

I believe the M50 has a place for an alignment pin that locks the flywheel. Can you put the flywheel back on with 2 bolts or so and stick a 10d nail, or other suitable rod thru the hole in block near starter that lines up with hole in flywheel?

Paul Shovestul

So the M50 is on an engine stand, flywheel removed and I'm planning on removing the head one evening this week (when I'm not skate skiing or drinking). Without too much investigation, it seems that the most common wy to ensure the crank does not move is to lock it via the tranny/flywheel, BMW tool 'bla bla bla'.

What , if any, is the best way to lock the crank without the tranny/flywheel installed?

Any advice appreciated, lots of pics to come when i get them off the camera,

Dave M