The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: Topdad on 29.05. 2012 11:49

Title: Bike now incontinent -I'm happy!!
Post by: Topdad on 29.05. 2012 11:49
Had a very nasty experience with the bike recently made worse because I'd caused it! Some time ago there was post about inline non return valves in the oil lines which saw the experienced guys more or less saying don't use them. Well I'd forgotten that I'd fitted one of these things and due to other household commitments ie "she who must be obeyed" I've not been using the bike much this year and finally got round to a day when I had a spare hour ,time for play!! or so I thought.
The old girls an easy starter ( bike that is , I could almost hear the keyboards being bashed in Oz ) and as usual 2nd kick she was burbling away happy days ,until i checked the oil return to the tank then PANIC , let her run for a min still nothing .I cleaned the presure release valve and reset the ball ,no change ,checked the pump everything clean and tight and turning over and after putting the cover back turned my attention to the oil lines which it turned out should have been first!!! I saw the non return valve whizzed it off and the oil line poured out the clean engine oil once tied up to stop the flow so I put the valve in the vice and couldn't move the ball stuck solid .I prised out the circlip non to gently, and removed ball and spring with some effort and got a clear run view through it and  has I had misfiled (lost) the original I had to use the "ex" non return has a connector duly reconnected the line I checked the
other line for any foreign bodies( no offence intended overseas members ) and has all was well put it together and started her up again , lovely sounds as usual and the return feed was trying to get through the tank side ,result!! I've learnt a very important thing  which is that that if in a discussion on this forum something is highlighted as a potential problem take note and do something about it ,don't has I did, just take it for granted that it would keep working and be okay and don't use nonreturn valves , anyway Thats why I'm reasonably happy to return last night to a small puddle of oil under the old girl, happy days best wishes BobH
Title: Re: Bike now incontinent -I'm happy!!
Post by: lawnmowerman on 29.05. 2012 12:37

I had a similar experience with NR valves but with a slightly different outcome.

After reading all the warnings on the forum regarding NR valves I prised the ball and spring out of the NR valve fitted by the PO when I did an oil change and used the body as a hose connector as you did. The bike was being run on straight 40 but I refilled with 20/50.

All was fine and I was using the bike on an almost daily basis for a couple of months.

She then sat for about a month and when I started her up she spat a crankcase full of oil over the garage floor. The NR valve was obviously doing its job in preventing wet sumping but I did not want to experience a stuck ball as you did.

I have obtained an oil valve from A W Dove for £40 inc UK postage which is a full flow ball type as used on oil and gas systems with a built in mag kill switch to avoid starting up with the oil off. They are primarily made for AMC bikes which are notorious wet sumpers. I just need to work out the fittings and perhaps a bracket so it sits vertically on the end of the angled oil tank outlet rather than routing the pipework across the top of the gearbox.

The usual procedure is to remove the crankcase drain plug if the bike has been standing and drain off any oil which has collected in the sump but personally, once I have decided to go for a run I do not want to spend time doing that. I would rather use an oil valve.

Having removed the ball in the NR valve as I did you may well experience wet sumping and end up with a rather bigger oil puddle under your bike!

Title: Re: Bike now incontinent -I'm happy!!
Post by: Topdad on 29.05. 2012 12:56
Jim, certainly is I looked this morning and theres a fair bit there ,i'll sort it out at the week end and then decide how to go forward , don't think i'll use a valve again though anyway. Please keep me updated with your valve regards BobH
Title: Re: Bike now incontinent -I'm happy!!
Post by: muskrat on 29.05. 2012 20:53
Ah, your starting to learn about Aussie humor  ;).
My '51 is the one that wets it's self. Just a minute or two to drain the sump and top up tank. Would not dream of using one of those valves.
Title: Re: Bike now incontinent -I'm happy!!
Post by: Ted_Flash on 30.05. 2012 08:25
A safe alternative is to use the external anti-wet-sumping-valve in parallel with a suitable cut-off valve in the oil supply line.  Therefore if you forget to turn the cut-off valve back on, then the a-w-s-v will pass oil, but if the a-w-s-v fails then it doesn't matter as it's only a by-pass.
Title: Re: Bike now incontinent -I'm happy!!
Post by: Topdad on 30.05. 2012 10:52
Thanks Ted, not sure what you actually mean so could you clarify for me , I'm having the equivalent of a blond moment ,a picture would help if you've done this cheers Bob.
Title: Re: Bike now incontinent -I'm happy!!
Post by: lawnmowerman on 30.05. 2012 13:29
Hi Ted. Not sure I understand either.

If you experience the same problem as Bob, ie non return valve ball stuck in the supply line and insufficient suction from the pump to break it free, the external oil shut off valve in parallel will make no difference if you forget to switch it on when you crank up.

There are many diverse opinions on this topic but IMHO, if you do decide to go for a shut off valve in the oil feed line then it must be a full bore valve and it must be foolproof.

I have seen a couple of failsafe arrangements, the first, which I use, being a shut off valve with a built in switch which earths the mag end cap and kills the spark, the second which I saw on a Commando on ebay was a large 15mm lever valve wich was mounted in such a way that when the kickstart is operated, it hits the lever and turns the oil on.

Whatever you decide to use, it is best to get in the habit of removing the oil filler to check the level after a run and again before starting - if there is a dramatic diffence in levels it is either in the sump or on the garage floor. Also check the oil returns to the tank when the bike is fired up before replacing the filler cap.

Title: Re: Bike now incontinent -I'm happy!!
Post by: Topdad on 31.05. 2012 10:21
Jim , certainly a habit I'm glad i have, always within a min of statring her I check the return saved me this time and in the past ! Only time I forgot ,due to having waited outside Eddie Dow's place in Banbury for it open after I'd lost a spring link in the rear chain for over 2 hours .Result during that time something stopped the oil return in my mad youth's rush to get to London I started her jumped on and only got has far has Wheetly hill ?? just outside Oxford before she lot go and how rod right through .Had to leave the bike in Acton never to be seen again and I came home sans bike by coach ,lesson well learnt, regards Bob.