Maybe compare the ANSI standard with BS46 for imperial keys? I think Simply Bearings stock imperial sizes.

I think Ray just got a taste of our international Ariel community! Canada, Slovakia, Holland, UK so far; I'm sure several other countries will soon be represented on this thread.

Welcome aboard Ray, you've come to the right place for support & enthusiasm to keep you going!

The black Ariel book is shown here - it's absolutely invaluable:

http://www.arielownersmcc.com/buying.html

You need another key. There should be no play in any dimension - the only thing you should ever have to do is a bit of deburring or perhaps lose one of the pointy ends, e.g. if the gear is close to a thrust face.

From the pics in my blog, they look like 5/16". They'll be BSW.

Well, my first false call. Just managed to get to the previous owner, who tells me - that has Dave said, the Gauge is not connected - so Sorry to bother you guys! I couldn’t see how it went through the tank and where if at all was connected - learned though, so now…..Phew… So now is ask is it worth...

Can we get that type of volute spring? Drags list this one: https://draganfly.co.uk/shop/72243/volute-spring-for-cables/#6492A-37 This is the symmetrical - two small ends, fat in the middle, type we use for decompressor cables on singles. I've had one of those on my four, and was/am concerned that t...

The same arrangement is used on the cast iron 4G. For both of my 4Gs, I have used the volute spring and found it satisfactory. I understand the preference for the coil tension spring but wonder whether it isn't a greater hazard if or when the spring breaks. The coil tension spring on Madam's 1927 S...

This might help. You can see the bracket attached to the carburettor mounting stud - the volute spring normally goes between this and the butterfly lever.
As you can see, I don't use the volute spring!