The stock original type Allen head bolts are known to have the heads snap off too. Best to replace them with standard highest grade Metric hex head fasteners. or some quality fasteners from ARP. This is not just a BMW problem here the Husky 449's and 511's are the same thing and use the same fasteners.
See below: This post is from another forum: and is from only 2 weeks ago.
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Originally Posted by
Tims1572
There have been many occasions that the stator screws or flywheel screws have come loose on the 450 BMWs and the 449/511 Husky's and it has torn up the stator like in the images posted by Doowrag above.
If you haven't already taken 20 minutes and looked inside to see the condition of the fasteners for the stator in the left case to check yours out. Please do so to make sure everything is tight. If any of the screws are loose, I would remove and replace them if you have new ones as BMW suggests. A good clean with some brake cleaner or equivalent and a blast of compressed air then use some Loctite for a hot and oily environment.
I would strongly suggest that you do this inspection as it could save you a bunch of cash and headache not to mention a possible long push or tow home out of the bush.
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I have just given my engine a freshen up and followed Tims advise and have dodged a bullet...thanks Tim. The head of one stator screw twisted off without any effort while checking with an allen key
I was only moments away from a costly failure. These screws have a 3mm dia hole that extends down to the first thread, which is where mine broke. A 3mm hole in a 6mm screw severely reduces the cross section, WTF was BMW thinking
I couldn't believe it when I picked up the screw head and could see straight through the allen key recess and 3mm of shank
Has anyone else noticed this on these screws? Tim could you check your spares?
If you have a close look at this photo provided by Doowrag awhile back you will notice a number of screws have broken at the junction of the shank and thread. This is because the cross section has been
SEVERELY reduced at this point as a result of a 3mm hole/counter bore which extends down to this point from the base of the Hex.
Suggest(unfortunately in packs of 5 - you will need 2 packs)
ARP Kit #: 760-1016
Metric Thread Bolt Kit
ARP Stainless
M6 x 1.00
12mm UHL
8mm Hex wrenching
Torque Value*: 11 ft-lbs (14.9 Nm)
OR
ARP Kit #: 660-1016
Metric Thread Bolt Kit
8740 Chrome Moly
M6 x 1.00
12mm UHL
8mm Hex wrenching
Torque Value*: 11 ft-lbs (14.9 Nm)
*Torque value in repair manual is way too high at 25nm