Models D and LD - Left hand threads

[Big Al]

In my Servicemans Book and my Home Workshop Manual, reference is made to left hand threads on (1) the 17mm nut retaining the bevel gear on the gearbox side of the crankshaft, and (2) the rear hub nut locking screw but only on early models.
Surely the flywheel nut has a left hand thread? I can find no mention or warning about this in my books.

[Steve J]

The 17mm nut holding the crankshaft bevel gear to the crank is indeed a left-hand thread.
The left hand thread in the rear hub is for the locking screw, which passes through the hub retaining nut into a LH tapped hole in the axle shaft. The hub nut itself is a normal right hand thread, same thread as the Li/Tv/Sx/GP rear hub. Later D/LD models didn't bother with the locking screw (it didn't work very well, apparently), and used a conventional single turn spring washer.
The flywheel retaining nut on the D/Ld crank is a normal right hand thread - the flywheel rotates in the opposite direction compared to the Li/Tv/Sx/GP. No need for a left hand thread there!

[Big Al]

Many thanks Steve. That explains why there is no mention of the thread on the flywheel nut in the books!

[Steve J]

No problem - there's also no mention (anywhere) of the torque figure for the D/LD flywheel nut! It's a relatively small diameter thread, so be careful not to over-tighten it.

[Big Al]

Good point. Thanks.