M60 crank nut

[bubba966]

Have a question or two about getting the crank nut off an M60.

What size socket do I need?

Standard thread or reverse thread?

Do you think a 340 ftlb airgun would pop it off? Or would I need a higher powered one?

Any tips for pulling it off?

Thanks for any help with this. Would be nice to get the front timing cover off so I can install the new one and get it running again...

[h2oyo]

Have a question or two about getting the crank nut off an M60.

What size socket do I need?

Standard thread or reverse thread?

Do you think a 340 ftlb airgun would pop it off? Or would I need a higher powered one?

Any tips for pulling it off?

Thanks for any help with this. Would be nice to get the front timing cover off so I can install the new one and get it running again...

I tried checking through the Bentley but didn't find what size socket is needed, It did look like it torqued down to 300 ft lbs plus or minus 15. Hope that helps.

[bubba966]

Thanks. Guess I shoulda mentioned that I found absolutely no info in the bentley for pulling it off. And that I'd heard that it's torqued to 325 ftlbs. I've not had any experience with air tools before so I'm not sure if a gun that's rated for 340 ftlbs will actually produce that much torque, less torque, more torque. Hence me asking if that'd do as it's 40% of the price of a 500 ftlb gun.

Or should I just get a breaker bar and a really big pipe?

And I can only guess that the nut is either 28mm or 29mm as it's smaller than the 30mm end on my fan clutch wrench.

I guess biggest question is which way is it threaded. Don't want to be tightening it even tighter than it already is.

[bubba966]

Was just trying to look it up on realoem to see if I could get any clues about it and it looks like it's part #7 here.

http://www.realoem.com/bmw/showparts.do?model=HE63&mospid=47410&btnr=11_1233&hg=11&fg=18

That right? Also it says something along the lines of "not suitable for" and doesn't finish. Guessing it's "not suitable for reuse"?

[h2oyo]

Was just trying to look it up on realoem to see if I could get any clues about it and it looks like it's part #7 here.

http://www.realoem.com/bmw/showparts.do?model=HE63&mospid=47410&btnr=11_1233&hg=11&fg=18

That right? Also it says something along the lines of "not suitable for" and doesn't finish. Guessing it's "not suitable for reuse"?

I believe that the rated torque of air tools usually the bigger number is in reverse. I would think a few good raps with that gun and it should spin off. The breaker bar and long cheater never has worked well for me just because its difficult to lock the motor so it doesn't just turn. I would agree with the not suitable for reuse logic a lot of the bolts are malleable (SP) meaning they stretch when torqued and shouldn't be reused like head bolts. Why are you wanting to remove this? Oil leak? G/L let us know how it turns out.
Johan

[bubba966]

Yeah, the more I think about it the more I'm not wanting to reuse this bolt or nut whichever it is.

Need to get this off so that I can replace the lower timing cover. Lower timing cover is busted. The mounting for the tensioner pulley assembly for the PS belt is busted and that entire assembly broke off.

Don't ever get anything caught in your belts. The M60B40 produces more than enough torque to destroy things when that happens. I need new belts (totally destroyed), water pump (way too much play in the shaft after this), lower timing cover (tensioner assembly mounting bolt bent over and snapped off the mounting on the timing cover), tensioner (it snapped that right in half), idler pulley (bent that right up), and possibly power steering lines.

[Mr._Graybeard]

I've done this successfully with a V6 -- you might consider it if you're adventurous. You fit a socket on the crank bolt with a stout breaker bar, the handle extending to the driver's side of the car and parallel with the ground. Rest the handle on a jackstand or something else that's stable. After making sure everything is very stable and will not slip, crank the engine briefly. When I did this on a 2.5l Mazda V6, the starter turned like the wrench wasn't even there and loosened the crank bolt. YMMV!

[bubba966]

Interesting idea. But the engine is mostly tore apart right now and I'm not about to turn it over with no oil, oil pan, valve covers etc. And I still don't know for sure which way it's treaded.

[Ross]

No oil pan?
Just jam a stout bar up there somewhere to block the crank and give it hell with a long bar and a pipe if needed.
I reuse the bolts and never had an issue.

[bubba966]

Yeah, gotta pull the lower oil pan to get to a few bolts that hold the lower timing cover on as they go through the upper oil pan into the bottom of the lower timing cover.

Thanks for the idea on blocking the crank. Will just jam a 2x4 up there and go to it.

And I already ordered a new bolt and that goofy washer underneath it. So I might as well use the new ones. Bolt & washer was only $10, and the person responsible for the damage is footing the bill for parts anyways.

You don't happen to remember the exact size of the socket needed to pull that bolt off due you Ross?

[Dave M]

Thanks for the idea on blocking the crank. Will just jam a 2x4 up there and go ?

I tightened the crank bolt on an M50 block using this 'technique' when the block was on an engine stand. To this day, I believe I may have bent the crank. After putting things back together and starting the engine, the harmonic was visible wobbling and the whole car shook. I say "may have" because it could have been shipped to me in that state. The seller replaced the crank for free, but it may very well have been my fault. If I had to do this again, I would make sure that the crank was blocked in more than one place, so forces can't push it one direction.

Just sayin,

Dave

[Ross]

I tightened the crank bolt on an M50 block using this 'technique' when the block was on an engine stand. To this day, I believe I may have bent the crank. After putting things back together and starting the engine, the harmonic was visible wobbling and the whole car shook. I say "may have" because it could have been shipped to me in that state. The seller replaced the crank for free, but it may very well have been my fault. If I had to do this again, I would make sure that the crank was blocked in more than one place, so forces can't push it one direction.

Just sayin,

Dave
No way you bent the crank. Can't speak to the wobble but you didn't bend the crank, trust me.

[Ross]

Yeah, gotta pull the lower oil pan to get to a few bolts that hold the lower timing cover on as they go through the upper oil pan into the bottom of the lower timing cover.

Thanks for the idea on blocking the crank. Will just jam a 2x4 up there and go to it.

And I already ordered a new bolt and that goofy washer underneath it. So I might as well use the new ones. Bolt & washer was only $10, and the person responsible for the damage is footing the bill for parts anyways.

You don't happen to remember the exact size of the socket needed to pull that bolt off due you Ross?

27mm

[Dave M]

No way you bent the crank. Can't speak to the wobble but you didn't bend the crank, trust me.

I'll believe you, but when I was watching the crank deflect, it made me queezy. As the crank was confirmed bent by the shop, it was too coincidental for me to not feel a bit guilty.

I'll go with your version :D

Dave

[yaofeng]

I used a cheater bar. No. I did not replace the bolt. Although on hind sight I should have. I think it is a torque to yield bolt.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_540/DSC_2716.jpg

Yeap, it is a bolt.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_540/DSC_2717.jpg

[SnakeyesTx]

The crank bolt is a stretch bolt. You really aren't supposed to reuse it. A lot of guys on the E39 boards right now are talking about these recently too. They're on the average, breaking 2 to 3 1/2" drive breaker bars with a cheater pipe attached, so use that at your own peril.

I've recommended using a 3/4" drive breaker bar and anchor it steady against your shop floor and bumping the starter motor to do the hard work for you. :D