Wow super informative and very much appreciated 🙏🏻

Eddie,

That is not a "B", the prefix code is an "R".

Steve,

That is a foot-change gearbox for a 1935 OW or OW1 model. A little background first. It was derived from the optional 4-speed transmission offered for the S6 models from mid-1932. In 1934 it changed in detail; mainly the kick-start quadrant mechanism became constant mesh. In (mid?) 1935 they changed from a stub tooth gear form to involute. Now stub teeth are involute with a shifted profile so I am not sure just what they meant; but basically the tooth form changes slightly. Hence, don't run mismatched pre- and post- mid-1935 gears together. It is like running 20 and 14-1/4 degree pressure angle gears together. The 1934 & 1935 4-speed gearboxes were used on both the heavyweight ohv and side valve models; same internals but different gearcases to suit the different mounting points. The foot shift was an option, and entailed a positive stop mechanism built in to the end cover. From what I have heard it was not particularly good, as it was very sensitive to the spring rate being just right, and the springs operating in that curved bronze box in the cover created a lot of friction. They dropped the foot-shift option in 1936. In general the 4-speed boxes not very robust compared to other marques. Which is why a lot of racers and sprinters converted to other gearboxes like Norton. 

By my own list of tracking down surviving OW/OW1 models I estimate they made perhaps thirty total over two years. That would be a mix of hand and foot-change models. I have never seen an advert that said how much extra the foot-change option cost but I am sure it deterred most buyers. So a uncommon gearbox for a uncommon model.

I have a 1934 hand change OW1 and a 1935 foot change OW1. My '35 has a "K" prefix gearbox, so it still retains the older stub-tooth gear profile like the '34.


1934 "G" prefix gearbox.


1934 "K" prefix gearbox.

In the 37 years I have been researching OW/OW1 models I have not yet seen a parts list or exploded views. But the internals, excluding the foot change mechanism of course, did continue on in the 4-speed gearboxes of the Aero 500/600cc models. To be sure some early Aeros flirted with a very terrible floating bronze bearing on the layshaft, but the underlying components were for - and reverted to - ball bearings. So internal views of the Aero gearbox are representative for the 1934-35 ohv gearboxes. So some pics of that are included.


500/600cc Aero gearbox.


500/600cc Aero gearbox.


500/600cc Aero gearbox.


500/600cc Aero gearbox.


500/600cc Aero gearbox.


A 1932 Greyhound gearbox, but shows the same shift drum and forks as used later.

-Doug

According to Jeff Clew's book, that is a 4 speed 'box for 1932 OHV models F or G.

Eddie.

Please assist with manual/ parts list or exploded view
Thanks  Steve

OK - It may be there is not much it can still give, but at least we have to get a look. It might help another get to look like this =>

A friend of mine is clearing his father's house in Argyllshire and has found this in the basement. If anyone wants it he will put it in the van on Friday when he returns home to Buckinghamshire. 

He doesn't want anything for it (though I  doubt he'd refuse a drink!), he'd just rather not scrap it. It has been in the basement a long time!

Message me if you want me to put you in touch.

Thanks Eddie, I'll add that to the list

Check out the float chamber. In the bottom of the chamber there is a central boss with a guide hole for the bottom of the needle. Carefully clean it out with a sharp drill. Debris can accumulate in the hole and drag on the needle, causing an erratic fuel height (Severe cases can cause total fuel starvation!).

 Regards, Eddie.

Engines that use drip feed lubrication don't actually have oil rings as such.
They burn or blow out any and all surplus oil

So as your previous enquiry thread on this has suggested, the problem is much more likely
to be a crankcase full of oil, for whatever reason.
Investigating the lube system is more likely to pay dividends.

Leaving the oil tap turned on while standing, perhaps ?
Using too thin an oil maybe, so its all leaked down into the 'sump' ?
Damaged or blocked sump drain maybe ?
Someone has twiddled the drip feed rate up to MAX ??
Hopethishelps !

Does anyone know an engineer who can work on a 1926 EW 350.
I think the piston rings are broken and the engine is smoking a lot.
I live in the GREATER MANCHESTER area if England but don't mind if the engineer is anywhere in England.
Brian Shepherd
brian.shepherd28@virginmedia.com