Author Topic: Crankshaft bolt. How to open? (Read 3646 times)

suvi123 · « **on:** October 29, 2007, 09:37:01 AM »

I have little problem. I need to open this bolt somehow...don't know how. Anyone has any ideas. I tried with wrentch, but when i turn, then crankshaft turns, so i put a pile of wood to hold crankshaft in place, but still nothing. Is this bolt threaded backwards?

Febi Guibo · « **Reply #1 on:** October 29, 2007, 10:42:40 AM »

it's like, REALLY on there... there is a tool (basically a long pipe with a flange and threads you bolt to the end of the crank to hold it, use a *long* breaker bar to loosen the nut.

http://www.technictool.com/bmwtools.htm

tool ending in #150 is what it looks like.

kowalski · « **Reply #2 on:** October 29, 2007, 12:26:10 PM »

what i did was i did it with the engine on the crane. then i bolted a small open end wrench to the back of the crankshaft, and then bolted that wrench to the chain hanging the engine so that once it gets to a certain point it will not move without lifting the engine. then i got an 8 foot pipe and put it on my socket drive and it came right of with a bit of bouncing.

bmwman91 · « **Reply #3 on:** October 29, 2007, 01:43:20 PM »

Yup, it is REALLY on there (I believe the spec is ~240ft-lbs). I would be a little hesitant to use the crankshaft itself to hold itself in place directly...try Kowalski's trick out. Get 3-5ft of breaker-bar on there and go to town!

gearheadE30 · « **Reply #4 on:** October 29, 2007, 02:06:44 PM »

Its a lot easier to get off if the engine is in the car. All you have to do is put a ~3 foot breaker bar on that bolt and have the bar hanging straight down. Put a piece of wood on the underside of the passenger side frame rail and bump the starter. Make sure that the starter is off by the time the bar hits the rail or you will destroy the starter gear and the flywheel ring gear. It takes about 3 hits, and i know it sounds really bad, but it works and I have heard of a few people using it with no problems.

badboypolar · « **Reply #5 on:** October 29, 2007, 02:37:35 PM »

Since the engine is out of the car,
Get a 3/8" or 1/2" socket wrench that has a rubberized handle. Then use a good sized hammer (I use a 3 lb drilling hammer) and hammer away. Be sure you stand horizontally from it and check to be sure it is still firmly on the nut each time you strike.

It's like an impact tool but you "can" give it more ft. lbs of impact.

Additionally, IF YOU NEED TO, you can try adding a piece of wood where the crank shaft is. Use it long ways and make sure it is in and pressing againest the lower 1-2" of the cylinder wall. Make sure you check your cylinder wall afterwards for any damange.

You can also try using the freeze off stuff and/or WD-40.

Vladi · « **Reply #6 on:** October 29, 2007, 03:09:25 PM »

Don't forget to replace the bolt with a new one afterwards!

suvi123 · « **Reply #7 on:** October 30, 2007, 10:02:15 AM »

Thanks!

suvi123 · « **Reply #8 on:** November 01, 2007, 03:18:05 PM »

Tonight I fabricated this holding tool and tried to hammer loose the bolt, but nothing. I think that I need little bigger hammer. Hope that I won't brake anything.