Holland Norton Works: Anti wet sump valve #H08

Based on but not the same as the Velocette, the ball is much larger so as the ball drops under suction from the pump a larger X sectional area is created so no restriction to oil flow. The small bolt may be for bleeding/priming the oil pipe down to the pump. If the oil line to the pump is not filled with oil then the ball will not open. Gear pumps push much better than they pull hence the need to prime the oil line with oil, air is compressible so if the pumps sucks on air the suction will not open the ball.

I have a Velocette type valve in my oil line which if disturbed I prime with oil, on every first start of the day I run the bike with the oil cap open long enough so the oil being returned is fresh oil and not just the sump contents. That removes the greatest risk after a dry oil line, which is a valve stuck to its seat after a long layup. 

I see these are automatic in daily use - but not really automatic if they must be primed.  What is the problem with a valve and built in switch?  'Make' or 'break' depending if it is magneto or coil ignition.

https://www.feked.com/anti-wet-sump-oil-pipe-tap-with-switch-magneto-or-coil-ignition-systems.html

...is one example, but there are others - including one for Singles with magnetos.

... need to be primed when the oil line downstream has had air introduced - at least that's the case with the Velo one. When I had a Venom I used a syringe to make sure that line was full when changing the oil.

I've never heard of a Velocette valve failing.

Has anyone in the club fitted one of these? 
 

Does it work?

When I did my own version many years ago I reduced the spring tension until the column of oil it held back was 50cms high, it's the height not the volume of oil you need to hold back. I also found that with a steel ball against a steel seat the slightest piece of crud held the valve open and the sump filled, so I used a O ring for the ball to seat on and that does not have the same issues plus its less likely to stick shut after a layup.

I'm not a Commando owner but am interested in this subject as I want to fit one to my light weight. My first thoughts were to use a Velo ball valve, problem there is that it needs to be, more or less, vertical to function properly.  That would rule out use on a light weight (and the twins?) because of the angle its mounted at without some fancy pipework to achieve this.

I wonder how the HNW valve copes with this?  The Velo valve has adequate clearance all around the circumference of the ball hence the need for (near) vertical mounting.  How is the ball in the HNW valve guided?

Ideally an anti sumping valve should be mounted after the pump, anyone tried that? 

On the subject of Velo's, the nitrile ball is a red herring.  Owners have a leaky valve, blame the steel ball, fit a nitrile  ball, no difference!  As Julian W says trying to re-seat a (leaking) steel ball with a hammer is a waste of time. Some machining is needed to restore the edge the ball sits on.

While talking Velo, the anti wet sumping valve can cause as much angst as the clutch can to Velo owners. 

My Velo type valve sits horizontally, has worked for 20 years so it needing to be vertical is a red herring. The ball is moved by hydraulic action not by gravity.

I'm pleased your Velo type valve has worked.  The problem with the Velo arrangement is that the ball isn't guided.  Once the valve is moved significantly away from the vertical the ball will not find the seat.  Mounted vertical, the spring will push the ball towards the towards the seat and seal. It takes very little for the ball not to seat hence the problems that seem to plague some Velo owners.

This is why I ask about the internals of the HNW (CNW) valve, I assume the ball is guided in some way? 

An alternative that seems to be finding favour on various classic bikes is a non-return valve made by Yamaha, a slim compact device unaffected by orientation. I may use one of these if it is not possible to fit a valve after the the pump, where it should be fitted. 

Perversely the only valve I have had an issue with was on a C15, located after the pump inside the crankcase, so engineering wise in the best place. It was stuck shut, on starting the engine would show oil flow (I luckily had clear tube installed) but it would slow down and then stop within 30 secs, then after a minute air bubbles would come out of the engine in the oil feed pipe, the oil pump was sucking air between its joints and sending the air the only route it could. I took the crankcases apart 3 times and freed off the valve only for it to stick shut again, so on 4th tear down I removed the spring and ball completely. 

Can John Holmes recall how it was that the C15 valve was able to stick shut?

No I can't, I never got the valve to stop sticking shut but no idea why it did despite 3 teardowns, all I know is the only cure was complete removal, so I ended up with a wet sumping engine, as it was a daily rider it did not matter. The design was a light spring acting on a steel ball bearing which closed against the alloy of the crankcase, a direct copy of the A10 scheme. Never heard of anyone else having the same issue with a valve after a gear pump. Its because of this I refuse to accept that theory beats observation and stay open to theories sometimes being mince.

The nitrile ball is so the seal is good, steel balls on a metal seat are easily compromised by a small piece of debris stuck on the seat, when I found that issue I made the seat rubber and kept the steel ball. A secondary benefit is less likelyhood of acids in the oil creating corrosion which could potentially stick the valve shut after a long layup.

A steel ball on an alloy seat (have I understood this right?) seems like a recipe for poor sealing.

Yes, this was on a pre pump Velocette type valve and it wet sumped, so I took the valve apart and saw a tiny piece of grit/rust on the seat which I was able to pick off, it happened again a few weeks after after so added an O ring to the seat for the ball to press against and it has never wet sumped again in 25 years. The engine is a 74 and has the return line remote filter so the crud must be from the inside of the tank rusting or a particle entering the tank when the cap was off.

I'm no engineer, but aren't we tackling the symptom and not the cause? I know it would be a radical overhaul but- AFAIK, the plunger pumps on old Triumphs dont have a wet sump issue- is it realistic to re-engineer the Norton pump? Obviously a major redesign and machining facilities are required, but I'm sure there's a ready market, given that a bolt-on would be suitable for the vast majority of Nortons still running? Can we get Allen Millyard on the case?!! :0

The AMR of Tucson mods are well documented if you look for them. I use them and have posted the info recently on this forum. Best leave Allen to do a V4 Commando.

Anybody want my 850 wet sumping Twin 

I Have a need, no no lust for this V4 Commando .....

Guys you’ve all helped cheer up the dribbling blues !

The eternal wet sumping problem again. The problem is the solution! The pump should be in the sump drowned in oil. It will work forever and as long as the sump is to level keep working. Some years ago I built a flow test machine for Perkins Engines in Peterborough. Seventeen different pumps for five engine blocks, but multiple different power outputs. Immersed pumps only push oil around, and need a pressure relief valve to stop hydraulic locking in an emergency. I also worked for Mercedes F1 engines, and the engine had four oil pumps. Now we have a solution, how to achieve it? Best answers on the back of a postage stamp please.

Small 12v scavenge pumps are cheap and easily available, I wonder if it would be worth having a take off from the 'sump'  plug and a delivery back to the oil tank. Running it for a few seconds before starting should empty the crankcases. No more worries as to whether the anti drain valve is not turned on or hss stuck shut. These worries would then be replaced with ' is it leaking, or what if the pipe comes off instead!

Trouble is, my 72 only has the small sump plug. I worry about the aluminium thread in the crankcase when I have to take this out every week before a weekend ride. Careful tightening - not too tight but on the other hand tight enough that it doesn’t vibrate loose and drop the oil. Just as catastrophic as a failed valve. I think I may go the HNW way and add an oil pressure alarm!

Interesting to see how Mr Wells gets on with his.

Referring to Michael Coare's earlier post, Triumphs do wet sump.

In my experience a lot more slowly than Nortons. I could leave my 1969 650 Trophy for 3 months when going off to college in the 1970s but if this extended to 6 months then it wet sumped badly.

I'd settle for that with my Commando but after a couple of months the tank was well drained.  This now has a manual valve fitted in the feed line but also an oil pressure indicator switch and an oil pressure gauge just in case I forget to open the valve. I also use one of those disk lock reminder coiled leads to act as a 'Remove Before Flight' reminder.  So that's belt, braces and binder twine!

I like the look of the HNW valve but am happy with my arrangement.

Andy

Someone in the past did the scavenge pump mod.

I like these valves, since this summer, 3 failures, two were automatic, the other a manual type. One I know of at the Dutch rally last year. Keeps the likes of me, RGM, Norvil and others in a job.

Do I have one fitted, hell no. The bikes when sold were expected to be used daily /run often so the inherent design of of using a gear type oil pump would not be a problem.

Suddenly, now the bikes are left weeks on end the poor old pump is considered a problem, not the lack of use. 

Living on a hill, my solution is to gently turn the motor over once while on the stand (and free the clutch ),then roll down the hill and engage third gear. Allow the motor to rumble away for a 100 yards then gently open the throttle  and give the motor plenty of time to wake up.  My old body need a slow start ,so why not the old bike.   Get a hill.  Good defense against a tsunami and flooding .   My work partner was in Crabee Thiland on THAT day ,and I was at the beach there a couple of weeks later .