Quick Question - Should I Use Lock Washers on Flywheel Bolts?

[LarryMaine]

I am marrying up my 4140 rebuilt engine to my bellhousing, and the flywheel bolts did not have any split lock washers when I removed it. The bolts are not drilled for wire (I think this was only done on the Ns). There is no lock ring for the bolts. The bolt heads are slotted, but are not fully castle bolt heads. These were the same bolts I had on my 850. So, should i add lock washers, should I use locktite, or what. The engine is hanging on a chain hoist, and if anyone else has done this, you know that it is just a special experience trying to torque the flywheel bolts to 150 lbs without the engine swinging away. Thanks for any help, Larry.

 

[Jim.ME]

I am marrying up my 4140 rebuilt engine to my bellhousing, and the flywheel bolts did not have any split lock washers when I removed it. The bolts are not drilled for wire (I think this was only done on the Ns). There is no lock ring for the bolts. The bolt heads are slotted, but are not fully castle bolt heads. These were the same bolts I had on my 850. So, should i add lock washers, should I use locktite, or what. The engine is hanging on a chain hoist, and if anyone else has done this, you know that it is just a special experience trying to torque the flywheel bolts to 150 lbs without the engine swinging away. Thanks for any help, Larry.

Check the parts book for your engine. Any I see do not use lock washers. Most call out grade 8 self-locking capscrews. If I doubted the self-locking condition, I would use blue Loctite on them.

I would take a few minutes to lower the hoist and touch the engine down on something to stabilize it while torquing, rather than having it swinging on a hoist while trying to torque hardware. If you are having that "special experience", it is your choice.

 

[LarryMaine]

Thanks Jim, I think I will just go with the locktite for insurance. Got the engine resting on a floor jack with the chain hoist above, so it should let me get the torque right. Will be another couple of months to get everything done. Hopefully this time when I do go for start up, I will not break the gears on my bendix because I have the timing exactly 180 degrees off like I did on my 850 rebuild. Had the machine shop do the head with all new valves, valve guides, springs, retainers, deck planed, new wrist pins and bushings in the pistons with new rings, had the valve seats all reground and also lapped, Got everything lubed with STP blue bottle, all new bearings. Cam, cam gears, etc. were all OK as was the oil pump. Actually the pain in the neck part of this rebuild is the HD Industrial hydraulic package system rebuild. Thanks again, Larry.