Torque value for....

[denis4x4]

.....flywheel bolts???

[Gunmetal blue2]

You tighten the good then put the saftey wire on the bolts. Make sure you put the saftey wire on right.

[Joe K]

There is no comprehensive guide to torque values used on the Model A. The entire assembly was done "armstrong" method originally. Mostly done with calibrated to who knows what standards assembly line air tools or manual wrenches.

That said, modern guides to torquing ARE a guide - and more or less applicable to Model A fasteners.

One I use a lot is http://www.almabolt.com/pages/catalo...ningtorque.htm which shows grade 5 and grade 8 bolting in both fine and coarse thread series. They also have many disclaimers about plating and lubrication, both of which are worth keeping in mind when selecting a target torque.

Most Model A fasteners are not made to ANSI standard, but generally, if a bolt used on the Model A survives torquing to Grade 5 level, its probably good to go.

Some fasteners are a bit more than this: the rear hub axle nuts come to mind. For these I tend to split the difference between Grade 5 and Grade 8, and lean a little heavy on the Grade 8 side.

The flywheel to crank flange bolts are 7/16-20. The chart shows these (grade 5) as 55 ft-lbs (unplated)

Les Andrews shows these bolts as grade 8 (not really) and 65ft-lbs. According to the grade 8 chart above, this is conservative. (78ft-lbs) So I might go to Les' level.

If the bolts survive torquing - then they have probably seen the highest mechanical stress they will have in their life and will probably not fail in service.

Hope this helps. Les' fine book is a resource, but not necessarily the last word on EVERYTHING Model A mechanical. Use the Internet to "self check."

Joe K

[denis4x4]

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