mk1 steering column

[ateichert]

Can somebody tell me the thread size on the inner steering column.
Thanks Mike

[Exminiman]

I dont know, but do you mean the large nut that holds the steering wheel on ?

[Peter Laidler]

Is it the NUT thread that's knackered or the thread on the actual COLUMN? It's difficult to imagine how either could have failed.

If it was me, this is what I would do....... Find a local small engineering shop - or a local hobby/model make with a small lathe and ask him to 'chase' the threads on the shaft with a 'thread chaser' Once he's done that......., it should take him 10 minutes..... try the nut. That should have solved the problem!

If it hasn't, ask him to chase the internal thread of the nut. That's an easy job too. He will have the thread form and tpi. Just pickup the thread and let the tool do the rest. Simple

[Spider]

11/16" x 28 TPI UNS.

[Peter Laidler]

Thanks for that Chris. I often wondered what the actual thread was. It looked like what we used to call '...a thread on a diameter..' when we didn't know the answer

[Spider]

Thanks for that Chris. I often wondered what the actual thread was. It looked like what we used to call '...a thread on a diameter..' when we didn't know the answer

I often wonder where and why they dream up some of the threads in the car. Another that came up recently was the thread for he pressed rockers - it's BSF. While I have nothing in the world against BSF (or just about any) threads, it's like it's someone's parting joke as they were clearing out their desk and walking out the door, when nearly all other threads are of a unified form.

[Tim]

BSF sounds like a parts bin special, left over from the past. The Austin OHV car engines (A, B and C-series) can trace their heritage back through the 1200cc (almost B series) used in the A40 Devon to the WWII Austin K5 military truck. I'm pretty sure that the original A40 1200 used BSF threads, and the K5 probably would have too.

The K5's engine was actually 'inspired by' (copied from) a Bedford truck engine, which was really a Chevrolet stovebolt six, so the A-series is Chevrolet inspired.

My Morris J Type van is BSF. There's nothing wrong with it per se, once you've come to terms with the way in which whitworth spanners are sized. Trust the British to take something simple and make it complex!

Tim

[roger mcnab]

hi tim
you should try some of the old brit motor bikes for a mish mash of threads and spanners they were annoying mixture and very tricky that you did not mix them up you needed a lot of spanners of various types or a good set of adjustable ones cheers roger

[Tim]

I know Roger! In my shed I have a '55 BSA with mostly British Standard Cycle threads, with whitworth heads, but also one component that has a 20mm metric head (not even a size in my socket set!). Then the J Type is all BSF (except where its BA). The '69 Triumph was in the transition so is mostly UNF, but still has a few odd BSCy. The Mini and the Moke are mostly UNF, and the moderns are all metric.

The problems arise when the thread forms and diameters are almost the same. Some of the BSCy and some BA are almost dead-on for metric. But not exactly.

Tim

[roger mcnab]

hi tim
i have a t100 daytona that i am building up with yamaha running gear it is 1970 mostly unf except for the tappet adjusters and some other thing i can not rememberi started out with just a cranck case and sourced bits from every where new crank from cobs spares swept back pipes from same source barrel and pistons also rh and lh monobloc carbs from luke at brit cycle head from us goldie mufflers from classic bike spares uk and other bits from the net
1 day i might get it going engine looks great dry assembled

well cheers for now roger