AJS & Matchless Owners Club

Peter Morris wrote:Hi All,

I'm looking for a anti wet jumping valve for my G3c, I don't trust myself with a tap. Has anyone used one of these type valves? http://www.ebay.co.uk/itm/6mm-to-12mm-B ... qWbJ7nI0Uw

I had a small one of these, took it apart and now I'm not exactly filled with confidence it this type.

My other bike has a stainless valve that looks a much better part (please see pic), I have searched on the internet and cannot find one like it. Does anyone know a supplier please?

Thanks
Peter

the type you quoted from e bay has a very soft spring on a diaphram, it works ok for me as it will fail safe, which is the main thing! regards david

can someone please post a link to the tap (mentioned earlier in this thread) with and electric switch function which cuts out the ignition when closed. Thanks

ANTISUMPING TAP fitted with ignition cut-out switch for AMC singles and twins. I can supply taps for all makes where there is room to accommodate them. Further details from A.W. Dove, 41 Princefield Avenue Penkridge Stafford ST19 5HG phone 01785 598616 email

david pollard wrote:

Peter Morris wrote:Hi All,

I'm looking for a anti wet jumping valve for my G3c, I don't trust myself with a tap. Has anyone used one of these type valves? http://www.ebay.co.uk/itm/6mm-to-12mm-B ... qWbJ7nI0Uw

I had a small one of these, took it apart and now I'm not exactly filled with confidence it this type.

My other bike has a stainless valve that looks a much better part (please see pic), I have searched on the internet and cannot find one like it. Does anyone know a supplier please?

Thanks
Peter

the type you quoted from e bay has a very soft spring on a diaphram, it works ok for me as it will fail safe, which is the main thing! regards david

David, could you explain how this valve is 'fail safe' please. I thought that all these anti-drain valves held the ball (or diaphragm) against a seating under spring pressure. The suction of the oil pump, when the engine starts, then lifts the ball off its seat allowing oil through to the pump. I would have thought that it could (in theory) fail to open if the suction was insufficient, so it's not clear to me how this is 'fail-safe'. Am I missing something here?
Cheers, Bob.

good morning bob, i purchased one of these back in 2015 from reline_7000, who now appears to be off e bay, i recall at the time i questioned the fail safe element, and on receiving it, took it apart to check it, it has a small diaphragm held in the closed position by a very fine hair spring, which, if it broke would allow the diaphragm to fall down away from the oil flow, ie, inlet, thus oil would have no restriction. before fitting this i used for some ten years a brass body unit sold by Conway motors, Vincent parts, which was satisfactory, but relies on a long spring holding up a 1/4 ball bearing. i concluded that this newer type was an improvement! i hope my trust is fulfilled!!, touch wood, no probs over the last two years and 4k miles, but of course there is no grntee!! regards David

If you do fit an anti wet sump valve use a Velocette type. I have had velos for 45 years and none have suffered a seizure.
Mick Hemmings supplies an in line version that uses the Velocette valve parts