Well prep work for France started this weekend & with not a lot to do this year, it's generally service related & basic maintenance

First surprise, it started first kick, a combination of my re-worked magneto & fuel additive in the tank. After a few seconds choke is off & it's ticking over with a nice solid thumping sound - great !!

Oil circulation looked good although the return looked excessive ?

30 seconds later it begins to smoke like never before, I had to stop the motor as it was blowing in on top of the locals

I suspect it has for the first time wet sumped - I have always seemed to be unaffected by this, but it now appears not any more

Is smoking soon after starting a common feature of wet slumping ?

Or do I have a bigger problem ?

Any suggestions ?

Job

email (option): Jonnyob1@googlemail.com

hi John i think you are right my bike used to wet sump a lot but it dos not anny more, ussaly it would get to its normal tepmature what ever that is and smoke nice blue smoke than i would drain it and would be fine drianing it is no biggy and remeber to put new oil in the tank

email (option): evandeweerthof@yahoo.com

Definitely wet sumping John. Most of my Norton's wet sump and my 16H emptied the contents of the oil tank over the bench in about a week. I lapped in the oil pump although it wasn't even bad and I knew I had to do something more to stop this. I don't like oil tank taps as it is an accident waiting to happen, so I bought a very discrete valve that screws into the crankcase as near the pump as you can get. It's got a very light spring and even sucking on it will open it. I check the oil indicator and it's always good and no more wet sumping so I'm pleased with it.

email (option): horror@blueyonder.co.uk

yes it is wet sumping...but sounds as tho its because the oil is not returning to the tank rather than the oil passing the valve on the supply side...easy to check....fire it up & keep an eye on the return feed into tank

I get a little wet sumping, not too bothered about it. I will not use one of those valve additions although I did consider one. If the ball inside gets stuck....so I don't see the need to add another 'cog in the wheel'

I had suspected it was wet sumping but as i had not had this happen before i needed to ask

Oil is returning - rather excessively i thought but no oil dumped on the ground which i thought might gave been the case

Is there any harm running the motor until the smoke clears or am i best to take the bash plate and sump pan off and drain

Best regards

Job

email (option): Jonnyob1@googlemail.com

Hi John

Isn't there a hexagon plug corresponding with a hole in the sump plate?

Thinking about it I seem to recall I had a set KM20 cases without the plug, or did I dream it?

Rob

email (option): robmiller11@yahoo.co.uk

John. In my sump plate there is a hole under the drain plug. No need to remove the four bolt oil pump plate. No harm to run the engine if you can get it started and you don't mind the smoke and as long as there is still some oil in the tank to feed the big end. It will return the oil in about 5-6 minutes. Ron

email (option): ronpier@talk21.com

Rob,

No you are not dreaming. I have a set of early crankcases (KM20.215) which doesn't have the drain plug. The later KM20 models did have the drain plug. I don't know at which point they switched over to fitting a drain plug.

Regards,
Leon

email (option): leonhop3@planet.nl

If the bike is unused for long periods it is best to try and cure the wet sumping...or at least reduce it to a minimum. Oil leakage past the main bearings into the primary cases can lead to contamination of the clutch and the requirement to strip all that out as well before the bike can be used..
Personally I'm not a fan of anti drain valves for reasons outlined at length in previous postings.
My first move would be to check the anti drain valves that are already in the engine to ensure those are functioning correctly.
Another option is to fit an 'on/off' tap into the feed line but arrange it so that it earths the mag, thus ensuring it has to be opened before the engine can be started...
Another option if you know the bike isn't going to be used is to remove the crankcase drain plug and put a drip tray under the bike...All the oil will eventually leak out, but at least it won't get to the clutch...or instead, drain the tank completely at the outset.
However, leaving the bike (engine) standing for long periods isn't a great strategy...It should be ridden now and again or at least started and warmed up on a regular basis. Apart from the obvious benefits, that would also eliminate any worries about wet sumping....Ian

email (option): ian@wright52.plus.com

I've seen on/off oil tank valves with a microswitch to cut out the mag and these are great for K2F mags or coil ignition, but how do you earth out a Lucas M01L magneto..?

email (option): horror@blueyonder.co.uk

Hi Horror, You have to rig up a wire from the HT side..Either by connecting it at the plug if you don't use a plug cap or by cutting into the lead itself to make a connection...That is a little more involved to make a neat job...Ian

email (option): ian@wright52.plus.com

Ah ok, thanks for that

email (option): horror@blueyonder.co.uk

Ian Wright

Hi Horror, You have to rig up a wire from the HT side..Either by connecting it at the plug if you don't use a plug cap or by cutting into the lead itself to make a connection...That is a little more involved to make a neat job...Ian

email (option): welbike@wish.net

Hi Lex..To make the 'center contact' type earth in the contact breaker cover would require the use of the wrong cover clip as the clip picks up in a recess pressed into middle of the cover. However, fittng an insulated, sprung loaded contact would be pretty straight forward with only relatively minor mods..Cutting into the HT lead doesn't carry any particular risks as long as it is carried out effectively...Suppressors, anti theft fittings and spark intensifiers are all fitted into the lead...Ian

email (option): ian@wright52.plus.com