anti sumping valve

youngjohn

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Non-VOC Member
The Velocette Venom & Viper have a ball/spring anti sumping valve fitted as standard. They work perfectly as long as the system is primed. Oil pipes must also be well connected with no air leaks. It's very easy to do. I have an aftermarket valve on my old Norton 16h and it also works very well. Makes the bike a lot more pleasant to own. Luckily my Comet doesn't seem to sump, so I'll leave well alone.
 
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Kevin Fowler

Active Forum User
Non-VOC Member
Thanks ET43 or can I call you ET, I have given much thought to the same issue, hence the anti sump valve. I also siezed a Velocete MAC, as per John 998 .hence the questions.Still interested in a photo of an instaled valve
Kevin Fowler
 

ET43

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Non-VOC Member
Hi Kevin, I used to be called Pushrod Prim in pre Vincent days, hence the ET43 title. There is a picture of an antisumping valve on the Conway Motors web site, as fitted to a Comet which appears to have a different feed oil line route to that of the twin. All The Best ET43
 

Hugo Myatt

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VOC Member
Hi all,
I have Conways anti-sumping valves fitted to my two Comets and my Rapide. The Comets work perfectly. However the Rapide did pass some oil into the sump, although by no means all, after a very long lay up. I don't know whether this is significant but on the Comets the valves are fitted almost vertically but on the Rapide, owing to the lack of space around the battery etc., the valve is nearrer the horizontal. It is absolutely vital to prime the oilways. Personally, being of a nervous disposition, I frequently check the return feed in the filler neck and the oil level in the tank.
Hugo.
 

Peter Holmes

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Without in any way wanting to denigrate the Conway Motors anti sumping valve, I purchased one of these a few months ago but simply lack the courage to fit it, its arrival coincided with various posts on the forum, one from my old buddy Marcus Bowden recounting stories of overheating and oil starvation, and yet another old Vincent owning friend of many years, Hugo Myatt has three fitted, all i can say is that when I try to suck the ball of the seat it seems to takes a lot of suck, but I have no way of judging if that is a good test. i guess it comes down to that time honoured phrase lifted from the Dirty Harry films 'Do you feel lucky punk, well do you' I don't know if I do. A good few years ago I decided to do without the T32 to improve the oil flow, DILEMMA!
 

youngjohn

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Non-VOC Member
As I mentioned earlier - every Velocette Venom and Viper ever made has the same design valve as standard. They are very hard to unseat if you suck through them, but the oil pump manages just fine. As long as the system is airtight after the valve and it is primed they work perfectly. Once they are primed, you don't have to worry unless you remove the pipes or the valve. I guess because there is one on my Venom and the factory fitted it, I'm used to the idea, and I don't have the reservations some others may have.
 

Bill Thomas

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VOC Member
Hello Peter, for the same reason I don't use an oil filter, when ever I have blown a Vin up, With a filter, there is still rubbish all over the place, So I feel I get a better flow without one, any thing heavy should stay in the oil filter housing anyway !! Cheers Bill.
 

ET43

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Non-VOC Member
Aha! Fit a remote filter and your worries are over. After fitting a remote filter which eventually subsequently cut apart during a rebuild, it was found to be absolutely contaminated, whereas the paper filter that was fitted in the normal place when cut apart, was spotlessly clean. I also removed the T32 and opened up the oil passage ways where possible to aid the flow. Whilst we are on about oil, newer owners might be aware that when topping up the oil in the ufm it is prudent to fill it to the platform seen below the filler neck, take the bike for a run, and then complete the topping up to say 1/2" above the platform. I made a graduated dip stick hung from the cap where the graduations started at the plate and were then marked for every 1/4 pint thereafter. Simple really! TTFN ET43
 

Tom Gaynor

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VOC Member
Great minds, etc, etc. I too have a dipstick, marked at the level of the platform. Good for piece of mind: if I can see the platform it doesn't mean I'm about to run dry, 1/2" below the platform means about 1/2 a pint is needed.
Yesterday I took the tank off, and "lagged" the UFM with best B & Q radiator reflecting foil, foil side in, 2 mm polystyrene insulation out. Four bits of double-sided sticky keep it in place. I've done this before, and it works: the oil actually gets HOT, and so there's little or no emulsion formed. (I have a catch bottle on the breather so I can check this). The only snag is that if one spills oil down the outside of the filler cap, it drips for weeks afterwards...
Apropos anti-sumping, I may just be astonishingly lucky, but my bike, with 5,000 miles from new double-start pump, doesn't sump at all. It might also be because here in the Great White North, oil doesn't actually flow very fast...
 
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