The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: alanaitch on 18.12. 2009 19:45

Title: Anti-wet sumping valves
Post by: alanaitch on 18.12. 2009 19:45
Hi all
I'm restoring a late A10 (with DA10R engine).  I've seen anti-wet sumping valves advertised a lot and wondered if anyone had a view on whether or not they're worth fitting.
Title: Re: Anti-wet sumping valves
Post by: RichardL on 18.12. 2009 20:00
Alan,

Welcome to the forum. If you have been lurking in the background, reading and waiting to join, you already know that this forum will be a great resource for information and camaraderie.

The topic of anti-wetsumping valves has been discussed here at length with, mostly, negative responses. Go up to the tabs where you find "Home", "Help", etc. and click on the "search" tab. Try entering the words "anti" and "wet" and you find many comments, not to mention the ones that are about to follow from other members as soon as I stop typing.

Richard L. 
Title: Re: Anti-wet sumping valves
Post by: Beezageezauk on 18.12. 2009 20:27
Hi Alan and warm welcome to the forum from me.

If you are in the process of restoring your A10 and have yet to strip the engine I would suggest that you replace the items that causes wet sumping whilst the crankcases are split.  This would be much, much cheaper than buying an Anti-wet sumping valve.

If you have finished the engine, wait until the bike is up and running and you might find that it doesn't suffer from wet-sumping.  Then you won't have any unnecessary expenditure in this area.

Beezageezauk.
Title: Re: Anti-wet sumping valves
Post by: 1660bob on 18.12. 2009 20:31
Personal preference here i suppose BUT... If you are rebuilding, then theoretically you will not need one.The primary cause of wet sumping is of course the oil draining by gravity down from the tank and seeping into the engine past the oil pump, the more worn the pump, the bigger the clearences and thus more room for the oil to seep past into the crankcase.If your pump is going to be re-conditioned/replaced it will then be in good nick,seepage will be at a minimum,and if and you use the bike reasonably often, you shouldn`t have any problems. If you splash out on a new, shiny SRM pump (££££££££££££££££) they insist that NO such valves are fitted in case they cause restriction in the supply line,HTH, Bob.
Title: Re: Anti-wet sumping valves
Post by: Richard on 18.12. 2009 23:14
now is the above actually correct or is it the ball not seating properly, the one behind the screw inside the crankcase behind the pump area? different opinions on this, I for one am anti SRM the advice they give is just there opinion, as is all the posts here  there is no reason to fit a more powerfil pump and I know they are a buisiness but they make money on the back of all the people that think they are the bees knees, there are a lot of other suppliers of parts at more reasonable cost.
As for the anti wet sump valves they are a boon if you do have a problem with the oil draining into the sump, many thousands have been sold with very few failures, in fact I would suggest that most problems could be attributed to human error, i.e. fitting the valve the incorrect way around, no proof here as no one would admit to that would they?
This valve is not something peculier to BSA's as I beleive there were manufacturers using this as standard on their bikes
Here endeth my opinion,oh and by the way I do have a valve fitted on the S/R and I am still awaiting the failure after three years of riding with it on
Richard
Title: Re: Anti-wet sumping valves
Post by: rocket man on 19.12. 2009 12:09
i and if it does fail it will kill your engine i wouldn't put a valve on Richard you may be a lucky one
if it wet sumps put a sump plate kit on they come with a bolt which has a magnet on the end
which is handy as it picks up metal particles mine has one fitted if your bike is stored over winter
and not used it will wetsump all you have to do is take bolt out drain oil check magnet with it being
newly built there could be some metal particles on it then at least its court them before they recirculate
in the oil in my opinion i would never fit a antiwet sump valve there not 100 percent guarantied to work
all the time if a particle of something gets in the valve whats to say it wont stop it working or if its a valve
that you turn off and on you might forget to turn it on and then it will cost you ££££££££££££££££££££££
to fix thats only my opinion
Title: Re: Anti-wet sumping valves
Post by: bsa-bill on 19.12. 2009 12:42
I'm with Richard on this one.
Everything that rocket man says is also true of the other THREE ball and spring valves that BSA incorporated in the design of the engine.
And please don't tell me the anti sump valve is different because it is sucked open instead of pushed open, the ball valve in the sump pickup is also sucked open.
This discussion has a touch of deja vu, and IIRC there was a request for anyone with experience of engine damage due to failure of an anti sumping valve to come forth, did anyone?
I'm also not a fan of fitting taps, even ones connected to a kill switch, just more opportunities for gremlins and senior moments, these days I would trust a ball and spring much more than my memory I'm afraid.

All the best - Bill (from a cold day in the UK)               
Title: Re: Anti-wet sumping valves
Post by: trevinoz on 19.12. 2009 21:00
Bill,
           I will come forward. I have seen the results of a failed valve on a Commando.
It was not pretty. It needed a crank grind, new pistons and rebore and new bearings.
Very expensive!
My opinion is that the oil had drained from below the valve which then had the pump trying to pump air.
Trev.
Title: Re: Anti-wet sumping valves
Post by: Richard on 19.12. 2009 22:12
Trev ,
How did the valve fail, as the ball has the spring under it and the pump sucks the oil past the seat, did it jamm up? as if it just stopped acting as a valve then the oil will pass the ball and it will just wet sump as it did before but still let oil to the pump, could it have been a case of something else that caused the engine failure and the valve being blamed?
Richard
Title: Re: Anti-wet sumping valves
Post by: Brian on 19.12. 2009 22:39
Much has been written on the pros and cons of fitting these devices, personally I see no need for them and would not under any circumstances fit one.

Like Trev I have seen the result of a engine being starved of oil. In my case it was a 441cc unit single that had a tap in the line and the owner forgot to turn it on. I got the job of rebuilding it, new bigend, piston etc etc. very expensive.

However, there are owners who choose to fit them and that it their choice, just remember if you do fit one and it fails and costs you a fortune to rebuild your engine then dont complain. Everyone knows they do pose a risk and occasionally do fail, if you are prepared to accept the risk then that is your choice.
Title: Re: Anti-wet sumping valves
Post by: Triton Thrasher on 19.12. 2009 22:44
Trev ,
How did the valve fail, as the ball has the spring under it and the pump sucks the oil past the seat, did it jamm up? as if it just stopped acting as a valve then the oil will pass the ball and it will just wet sump as it did before but still let oil to the pump, could it have been a case of something else that caused the engine failure and the valve being blamed?
Richard

My interpretation of Trev's post is that the oil between the valve and the pump drained down through the pump and the valve stopped oil from the tank taking its place, while the engine was stopped, so the pump lost prime.

If you fit a valve and the oil supply fails, the valve is the most likely cause.  What else would do it?
Title: Re: Anti-wet sumping valves
Post by: Triton Thrasher on 19.12. 2009 22:46
the ball valve in the sump pickup is also sucked open.
         

But can't destroy the engine.
Title: Re: Anti-wet sumping valves
Post by: trevinoz on 19.12. 2009 23:00
Richard,
             When there is no oil between the valve and the pump, there is no suction so the ball cannot be moved from it's seat. In my case, the valve didn't fail. If it had been primed it would have operated satisfactorily but I assume the bike hadn't been started for a while thus allowing the oil to drain away. It had worked previously so the owner assumed it would continue working.
I reckon any shut-off device is a disaster waiting to happen.
Trev.
Title: Re: Anti-wet sumping valves
Post by: MG on 20.12. 2009 09:23
As a mechanical engineer, I totally agree with Trev on this one. The oil pumps used in our BSAs are nothing but simple external gear pumps. In it's basic design, an external gear pump is not working well under critical suction conditions. This is a matter of fact and each serious book on work machine or hydraulic engineering will tell you so.

Have a look at this link, esp. at the part of "Installation issues":
http://www.e4training.com/hydraulic_pumps/B1.htm

Imho, if the pump is not leaking, the shut-off valve is not likely to cause any trouble, because it is easily sucked open by the primed pump. On the other hand, if it is leaking, it will run dry and might not be able to create enough suction to open the ball valve that is cutting off oil supply. The BSA engineers did well know why to put the ball valve on the pressure side of the pump and mounted the oil tank far higher than the pump itself to ensure proper priming.

The ball valve in the sump is a completely different story. It is NOT spring loaded, unlike the anti-wet sumping valves, so the ball will easily be lifted off it's seat, once the sump is running full of oil, so oil is forced to the pump within seconds just by hydrostatic pressure, if the oilway to the pump should be empty for any reason (like after a rebuild, for example)
And have you ever asked yourself why the BSA engineers fancied to put this valve there? Imho it's only task is to keep the oil in the oilway leading to the return side of the pump when the engine is stopped, in order not to have it run dry at startup.

Just my personal opinion, but I consider these valves to be a rather safe way to a complete engine rebuild, sooner or later. And if your oil tank is empty after just a few days without riding, you should do something about your leaking oil pump. It is a matter of curing the illness, not the symptoms.
Title: Re: Anti-wet sumping valves
Post by: bsa-bill on 20.12. 2009 10:38
OK gents plenty to ponder and it does really come to personnel choice of course.
As an aside after I rebuilt my Flash I removed the anti sumping valve as it was no longer needed, but as a stop gap cure it was brilliant.

All the best - Bill
Title: Re: Anti-wet sumping valves
Post by: Richard on 20.12. 2009 15:48
Well its god that we should agree that we will have different opinions on this, however my engine wet sumps whe I have not ridden it for a couple of weeks which is why I fitted the valve, having rebuilt my engine before I really knew about reseating the ball bearing in the inner crankcase and knowing my oil pump is not worn out, strange as to why all the blame on wetsumping is put down to the pump,I did not wish to strip it down again.
My engine has not been started for a few weeks so from what you are saying the oil will now be drained away and when I start her up to go to the Tappits inn run on Boxing day my engine will have no oil flow and I wil blow her up, wrong every time I have started her up after a layoff I check for oil return and it is there, so somewhere along this thread we have to look at all the facts and not just conclude the valve is the enemy, maybe the pump fitted on the engines that have failed with a valve fitted may in fact be the culprit and the oil starvation would have happened anyway how many of you have had an oil related problem on a bike with no valve fitted several I'll be bound.
Richard
Title: Re: Anti-wet sumping valves
Post by: rocket man on 20.12. 2009 15:56
bill your spot on its alright as a stop gap but not as a permanent solution
i would never trust one and maybe over a period of time it could wear parts out a lot quicker
if there is not enough oil to prime it on start up because the valve needs suction that first few seconds
when there is no oil in the line below the valve because its drained off and the pump needs to be full of oil
to pump will be causing damage over a period of time


dave
Title: Re: Anti-wet sumping valves
Post by: rocket man on 20.12. 2009 16:07
i found this on a norton web site (This is NOT the dangerous type of anti-drain valve, which is fitted by some people into the oil feed line above the crankcases. Anti-drain valves fitted into oil feeds, always cause oil starvation to the big ends for a brief time when starting the bike. If you use an on/off tap instead and forget to turn it on, you will destroy your engine in short order) i rest my case this is the web site http://www.ntnoa.org/wetsumping.htm

dave
Title: Re: Anti-wet sumping valves
Post by: bsa-bill on 20.12. 2009 16:23
The strange thing I found with wetsumping is that it did not happen every time the bike was stopped for a long period.
Led me to thinking in terms of could the position of the engine once it stopped have some bearing but I can't workout how this could be unless the pump drained out more in one position than others, another of my theories would involve oil backing up in the pushrod tunnel and draining out after the engine had stopped.
Far fetched ideas I know.
And to introduce a little bit of Irish - we only know we have wetsumping because we have dry sumps, we therefore have an advantage over wetsump desinq in that we know when we have a problem.

I'm off now -  due a pill     oh Toon 2 boro 0   *clap*

All the best - Bill
Title: Re: Anti-wet sumping valves
Post by: Richard on 20.12. 2009 19:11
Rocket man
You must remember that we all have our opinions about different things and because George wrote that on the Norton web site is no different from your or my writings on this web site.
This subject always makes for a good debate and I am sure it will raise its ugly little head again.
Its been good
all the best
Richard with the valve on his Super  Rocket
Title: Re: Anti-wet sumping valves
Post by: a101960 on 20.12. 2009 19:44
I am not convinced that the pump being in good condition is a reliable way of preventing wet sumping. My engine has done about 2000 miles since a complete rebuild which included a new pump and after about two to three weeks of non use the sump will need draining. At two weeks it is normally OK but after that it will need draining. There are several issues that will affect the time that it takes to wet sump like for instance temperature and oil viscosity. I once managed to pump a load of oil out onto the garage floor by neglecting to the check the sump level, but the bike had not been used for several weeks and I have only myself to blame. I am of the opinion that without anti drain valve wet sumping is inevitable, but I am not persuaded that they are free from risk so therefore I have not fitted one. I know of several people who like Richard have fitted an anti drain valve and have had no problems, in fact I know of one chap that has had one fitted to a Norton Dominator for years. Personally, I do not find it to much of a problem to drain the sump however I always throw the drained oil away and refill with new oil. There are those that say the original A10 timing side main bearing is a weak and should be replaced by something like the SRM conversion for reliability and there are people that have done thousands of miles without trouble. I have always wondered why the SRM warranty is invalidated if you fit a filter (Yes really) and do not use monograde oil. We all set up and run our bikes to suit ourselves and different people are motivated by different experiences. It is a question of individual choice in the end.
Title: Re: Anti-wet sumping valves
Post by: trevinoz on 20.12. 2009 20:29
If the check valve on the delivery side of the oil pump is ineffective oil will always gravitate to the sump no matter how good or new the pump is for the simple reason that gear pumps must have clearance around the gears.
Also, if the housings do not seal to each other, oil will leak from the body. There is no shaft seal on these pumps so there is another path for leakage.
The obvious solution is to start the bikes regularly. A drain plug in the sump is a good idea.
If I let my bike stand for too long and get a sump full, I just start it and let the oil pump do its job and clean up the mess from under the bike. I wish I had fitted a breather pipe and hose so I could collect the blown out oil easily.
As a point of interest, my Atlas suffers the same problem but with the high capacity pump and large breather hose connected to the oil tank the sump is cleared in no time. With no oil on the ground.
Trev.
Title: Re: Anti-wet sumping valves
Post by: rocket man on 20.12. 2009 20:44
hi trev you will have to be careful starting it with a sump full of oil it could hydraulically lock up


dave
Title: Re: Anti-wet sumping valves
Post by: RichardL on 20.12. 2009 21:32
I don't believe there is enough oil in the tank to fill the crankcase such that there would be hydraulic lockup.

Richard L.
Title: Re: Anti-wet sumping valves
Post by: BSA_54A10 on 21.12. 2009 08:51
To this arguement I always reffer owners to their local library.
Go and find one that keeps bound copies of old motorcycle magazines.
Have a look at the "help" colums.
You will find no one asking about a cure for "wet sumping".
It just did not happen as the bikes were new ( so most of the clearences were close ) , the oils were thicker when cold than modern multigrades and THE BIKES WERE DAILY RIDES, so everyhting was being used as it was designed to be.

Ditto for "stiction" in carb slides.
Ditto for mechanical regulators.
Ditto for breather valves,,,,

Get the drift ?

There are 2 principal problems.
1) we are using our A 10's in a mannar that they were not designed to be used.
2) We are judging them by 2010 standards and not 40's to 60's standards.

By far it is better to get one of the bolt on sumps with a magnetic drain plug.
Not only will it make life a lot easier for you cases but as it makes oil changing a lot easier it will also ebcourage more frequent oil changes and the one thing that there is no dissention about on this forum is that you can not change the oil too much.
Title: Re: Anti-wet sumping valves
Post by: MG on 21.12. 2009 12:00
I made the experience that putting the pistons on or near TDC really helps a lot, like stated on that Norton site.. It takes at least twice as much time for the oil to drain down. I guess the hydrostatic pressure from the oil in the big ends helps to reduce seeping through the pump and maybe helps the ball valve to close properly, but I'm just guessing here. Whatever the reason, it does help with both my bikes. I always wondered why it sometimes took more than a month for the oil to drain down, and sometimes just 2 weeks, so I tried different positions and watched the wet-sumping progressing.

BSA_54A10, I totally agree with you. It is just a matter of regular use. With my bikes, it is sufficient to ride them once a month, and the drain plug can stay untouched.
 
Imho after all it's these little imperfections that make the charme of owning and maintaining an old vehicle. I mean, (almost) anyone can get on a new japanese bike, press the start button and take off, but where's the "get-your-hands-dirty fun"?  *smile*

Cheers!
Title: Re: Anti-wet sumping valves
Post by: bsa-bill on 21.12. 2009 12:30
Think you hit the mark Trevor, I never considered wet sumping a problem, it smokes for a couple of hundered yards then clears and runs fine.
I'd love to ride the bike more and should do next year, it's probably those of us that don't get to ride as much as we'd like that spend too much time faffing about looking for faults to mend, I never did that when riding in the sixties, just jumped on kicked and left for the pub, Saturday mornings it got washed and polished and oil checked and that was it.
The only problems I ever had then were punctures and the dynamo chain and once and once only it wetsumped this after it had stood for about four weeks during harvest.

Interesting observation MG, kind of explains why sometimes it wet sumps and sometimes not.

All the best - Bill
Title: Re: Anti-wet sumping valves
Post by: groily on 21.12. 2009 16:55
Like MG, I try to leave the engine at near tdc and it does make a difference - but first time I've seen a plausible explanation. Use has to be the best answer. I made but then didn't fit a tap as it didn't seem worth it after all, but the after-market sump plug has been great the once or twice the oil's been lower than I'd like in the tank. Occasionally there's a squirt or two from the breather after start-up, but it's not a big hassle on a workhorse bike. It would irritate the heck out of me on a shinier cleaner one though, as it's hard to clean up down there. If I'd wanted to be a nurse . . .
But not apologising for using taps on one or two other bikes with notorious records on the incontinence front. So far Alzheimers has held off - and the ignition cut-outs haven't been tested. Not a topic I ever mention to the local bloke with the stunningly immaculate Commando and the un-wired tap that he forgot . . .
Title: Re: Anti-wet sumping valves
Post by: rocket man on 21.12. 2009 18:46
lets put this to bed now i mean lets finish this topic
we can all do what we want with our bikes fit a valve
or not we all know they wet sump because we dont use them every day like they used to be used
we just enjoy them now and again and its nice to have a bit of history to look after and we all enjoy tinkering
with them its part of the pleasure but i wouldn't fit a valve   *smile* this is my other bike i ride when i dont use the old girl
Title: Re: Anti-wet sumping valves
Post by: Triton Thrasher on 21.12. 2009 22:58
I made the experience that putting the pistons on or near TDC really helps a lot,

Have you not heard the theory that leaving an engine stopped long term near TDC is bad for the magneto?
Title: Re: Anti-wet sumping valves
Post by: MG on 22.12. 2009 09:15
 ???? ???? ???? ????
Never heard of that theory. But I could imagine it has something to do with the position of the winding yoke, that near TDC is not short circuiting the magnetic flux. But I wouldn't consider that a real problem with the AlNiCo-magnets used back then, because they hold their charge much better than the older ferrite ones. This had also been the reason for putting a piece of steel on the old (ferrite) horseshoe magnets when taking them out of the magneto body, for remagnetising for example. I've had several K2F bodies lie around for years without the armature and couldn't notice any loss in magnetism.
But for the older ferrite magnets this might well be an issue, actually never thought of that...
Title: Re: Anti-wet sumping valves
Post by: alanaitch on 16.01. 2010 14:14
Wow guys!
Thanks for all these responses; given that I'll be fitting a reconditioned oil pump (from Draganfly) I guess I'll see how that goes.  I also appreciate the comment that bikes should be started at least every couple of weeks if they're going to be laid up for some time.
Thanks again & please see another of my posts on torque settings.
Alan