AJS & Matchless Owners Club

Thanks Clive, I'll check that- feels like the solution is within reach!

Have a look at a topic I posted in January entitled 'Engine Oil filter'- there is quite a bit of information about the valve located in the crankcase- not the one on the end of the crankshaft.

Thank you Trefor, I will do

Thanks everybody for your help, I think we're nearly there. Got a look at the engine last weekend and what's missing is some of the engine oil filter (not sure why he hasn't got that from the original engine...) we do have the outer cap which seems to be the only part unavailable!
Parts arrived today, so hopefully it'll be back on the road soon.
Also managed to pick up a copy of Matchless Motorcycles by FW Neil, which should help (have got a PDF copy, but good to have the book in hand).
Trefor, the thread you pointed me at helped me join all the dots... Whereabouts are you in SA? My Mum lives on the Fleurieu (Aldinga Beach) I'd love to try and get to the Sellicks beach races, but never been there at the right time.
I now know a lot more about Matchless twins!

Very close to Sellicks Beach- about 30mins. I haven't been to the races but here are a couple of sites to keep you up to date. The Levis Motorcycle Club (levismcc.asn.au) organise the meeting and some coverage of previous races are on You Tube (Selecks Beach Racing SA - YouTube). They can't spell Sellicks but it is the correct meeting. Cheers.