A10 Wet Sumping - other fixes ?.

[beezermacc]

Re. Ethelred's remark. Attempting to start an engine which has wet sumped can cause a lot of damage. If the sump is full, as the pistons travel down the bores, the oil can't escape quickly enough through the various holes so the bottom end can 'hydraulic lock'. At worst this can damage the crankcases. At the very least it will blow gaskets and empty loads of oil into the primary side and vent it onto the garage floor.

[Ethelred]

Interesting point Beezermacc, certainly a theoretical possibility. Have you ever seen one blown apart as you describe? That'd take a seriously big leak to fully fill the sump such as to cause hydraulic locking. Certainly it's a good precaution to drain the sump after a long lie up, but for a bike ridden say every month is it really an issue?
I 'spose for peace of mind it's worth fitting one of these devices, but it does seem like overkill.

[Gerry]

Hi Guys, OK here's my pennys worth! I have fitted a check or non-return valve to my BSA C15 Pastoral 1965 in the oil supply line and which was advised by a member of our local BSA Club here in Adelaide. I purchased it from a marine store and its for an outboard motor fuel supply line. It cost me $20AU and has given me absolutely no trouble whatsoever. Its been in the oil line now for over 4 years and I get no wet sumping even though the bike may not have been started up for maybe three months or more. BUT I always check the oil return as soon as i start the bike. I went back to the store for another one for the A10 before starting the rebuild and the price had increased to $40 and the storeman said he had had an enquiry from the manufacturer asking why these were failing so often. He had to tell them old British bikes were to blame!!! As for the A10 I threaded the original sump plate 5/16 BSCY and fitted a bolt with a neodomine (is that the right spelling) high strength magnet into (pinched it from my misses jewellery box lid). The bolt is sealed with an 'O' ring........didn't need to fit the anti wet sumping valve........it doesn't wet sump!!!!!! whoohooo. Gerry

[RichardL]

It's a check valve.  Why would this work? Working properly it would let oil drain through as if it weren't there. Is the idea that the valve must be sucked open by the pump? Keep us posted and keep checking your return. I would sooner trust my memory with a gate valve.


Richard L.

[Gerry]

Hi Richard, Exactly, a very light spring is enough to stop wet sumping but not enough to stop the pump sucking the oil past the valve. The new one I purchased for the A10 I have here in front of me and if I suck the correct end it opens easily. But as I said before, I always check the oil return on starting the bike. I do the same on the A10 even without the valve. Its a habit that lets me sleep at night. I'll open it up and take some more pics' to show the guts of the thing. (Check valve for you but non-return for the British) lol Cheers Gerry

[alanp]

OK, I have a routine which works for me.....during the riding season (UK - summer months), regular/weekly riding clears out the small amount of oil which has drained into the sump with no affects on starting/running.......during the non-riding season (UK - the rest of the year), I disconnect the oil line which runs from the oil tank to the engine pump inlet at the engine case end and raise its end above the oil tank level, cover the end and tape it in position.....riding season begins, I reconnect the oil line.....simples.  This is particularly effective if you run 20W-50 oil which wet sumps faster than you can say 'wet sump' and you can lose the lot into the sump over the winter.

[Marqs1979]

I believe it is a matter of a well-seating ball beaing check valve behind the oil pump. (I'm sticking my neck out by citing this without reference to my books.) It could be that the spring behind your ball bearing is weak or the ball and/or seat are worn. I think you could epoxy a ball on the end of a dowel and, using some valve-lapping compound while twisting the dowel as if lapping a valve seat, assure a good seal. Obviously, this involves some dismantling and, less obviously, I could be completely off track.

Richard L.

Anyone have any pictures of where the ball is? I can not find a good clear picture or exploded view of this. Do you have to separate the block halves or is it sufficient to detach the pump? But I have had loose my pump, but I have not seen a spring and ball?

[a10 gf]

Anyone have any pictures of where the ball is?

Spring & retainer at the rear of the oil pump, must split the case to get to it
see http://www.a7a10.net/forum/index.php?topic=3066.msg20796#msg20796

Attached picture, ball seen when removing oilpump. One can poke it with a stick to check movement\spring strength.

Basically the same function as the springed valves discussed in the earlier posts (those being placed before the pump, working by suction). But, possible scenario, the oil inbetween the pump and the springed valve drains away, the pump empties & won't pump anything = + + . Whatever potential gain is not worth the risk. Just my opinion.

Personally I won't trust anything placed before the pump, apart from maybe this one.

[Gerry]

Well everyone to their own I suppose. I can only say the one above was recommended to me by a very experienced BSA Club member and I know there are others in our club with this type of anti wet sumping valve and there has been absolutely no problem with any of them. Most of our members are in their late 60's and above with a wealth of past experience. My C15 has had one fitted since first time on the road about 4 years ago and it sits for a month or two at times and usually starts with no smoke and a good oil return. I purchased another for my A10 but don't have a problem with that!!!.......so far. lol Cheers. Gerry

[alanp]

Just a word of caution for those with check valves who feel the need to check that oil is returning to the oil tank after start up..... Depending upon the amount of oil in the sump you will get a steady return to the oil tank momentarily while it empties any oil out of the sump and you need to wait until the oil return becomes a bit 'spitty' due to the oil return side of the pump exceeding the capacity of the supply side. Even with a perfect check valve some oil will drain into the sump from inside the engine surfaces so wait for the right flow if you don't 100% trust the check valve.

[a10 gf]

My concern with the 'springed' pre-pump valve is giving away control of the normal, direct gravity feed to the pump, something sticking in there it's goodbye to the engine while riding... A manual valve with some stiff mechanism would very probably never shut off by itself (most likely error would be\is the owner forgetting to turn it to 'on', if no extra warning mechanism fitted).

And as mentioned above, if for any reason the pump drains empty (weak spring\ball in the crankcase), it would not be primed and may not manage to suck open the valve on the feed side. With tank return looking good for a while... ref. alanp's post.

But hey, just theoretical, those springed valves may be of excellent quality (they must be!), and work fine for dozens of years for all I know.

[trevinoz]

And as I have said before, I have seen an engine after the valve failed to open! Not pretty and very expensive!

Trev.

[bsa-bill]

the oil can't escape quickly enough

I think the crankcase breather can handle a fair quantity of oil beezermacc (personal experience), also If it hydro-locked you'd need to be a pretty hefty kicker to damage anything other than your leg

It may seem from previous posts that I'm a fan of valves, no I'd prefer not to use them if not needed and mostly they are not needed ( none employed in my two bikes after rebuilds)

My concern is between valve and tap ( yes OK they are both valves) I believe the chance of a valve failing against the chance of me forgetting to turn on a tap is stacked in the valves favour, the addition of some device to prevent starting with out turning on a tap is balanced against there being something else to fail plus a tap itself is not perfect (read our mails re fuel taps)
I have read mails from people who know people who have had a valve fail, I suspect people who have forgotten to turn on taps are perhaps understandably not in a hurry to admit it 

[Gerry]

To all my anti wet sumping friends, and every one else on this forum, a very happy xmas, a very prosperous new year and may all your riding be safe. Gerry

[Ethelred]

thought Gerry got it spot on, 'Well everyone to their own I suppose.'

in my experience, you put 6 bikers together and you get 6 different opinions. We're a very tolerant lot though, which is just as well 

I do love a good wet sumping thead...

have a groovy solstice