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[rickofkexby]

Hi folks, has anyone got any useful tips to help lessen wet sumping on my J2? Has anyone modified the crankcase in any way to stop the problem? Thanks for any tips you can pass on. Rick

[vince]

Hi, do you mean while its running of overnight? Vince

[grindstaff]

You probably know it already but on Bullets some people advise leaving the piston at TDC when you park up; I'm not sure if it works with J2s though.

[grindstaff]

There's also this from our hosts, again, it refers to Bullets but they're pretty similar if I recall correctly. Had one once - really miss it.

https://www.hitchcocksmotorcycles.com/p ... umping.pdf

(Oh, for an edit button!)

[Chris Tindal]

I'm not sure if it applies to J2 cases, but forget machining a recess in the timing side for an oil seal like Indian Bullets. A previous owner machined my Redditch 500 cases but there's not enough meat and it cuts through into the cam recess behind. Would a new phosphorus bronze bush in the timing side crankshaft hole help?

[Adrian]

(Oh, for an edit button!)

Yes there is one now. Look in the top right-hand corner of your next comment when you post again, but be quick! It disappears after a while.

A.

[rickofkexby]

Hi, do you mean while its running of overnight? Vince

Hi Vince, thanks for your response. Over night is not really a problem or when its running. If the bike has been stood for a week or so and it eventually starts most of the engine oil is blown out of the breather at the back of the primary chain case.
I replaced the oil return disc to be sure that it is a good one ; I have stripped the engine to make sure that the flywheel compartment was sealed from the oil tank and I'm sure it was ok; the brass bush looks ok but I'll replace it anyway.
I've read that you should park the bike with the piston at tdc and I try to ensure that I do that, but if the engine oil is at the recommended level, 2 inches below the filler, does that make much difference?
What would make the problem more bearable is if the flywheel compartment could be drained easier, which is what I was getting at when I asked if anyone had modified an engine in any way to fit a drain plug.
I suppose I could run the engine breather into a catch tank at the back of the bike; has anyone tried this?
Thanks for listening, that's got it out of my system so I guess I'll just soldier on put up with it as I really like the bike otherwise.

[Marko]

If it helps: my model G which is very similar in design to the J2 will also wetsump . I've paid attention to the crankcase halves & made sure the oil is not leaking from the oil compartment into the sump, it doesn't. The oil that's draining down into the sump is coming from the timing chest & getting past the bush.

Its not a problem if the bike is used regularly (i.e daily) but leave it for a while & the engine will smoke & chuck out the contents via the engine breather. Saying that its not "too" bad & clears pretty quickly (oh & leaves a mess on the floor sometimes) after a minute or so.

I did contemplate H's modified breather (as sold for the Bullets), indeed bought one & fitted it to the G; it solved the "puking" problem however it just looked plain silly perched on the G's forward mounted oil filler! So I removed it. However, seeing & understanding how H's modified breather worked has given me an idea. What I intend to do is run the pipe that comes from the engine breather to the oil filler extension.
It might mean popping a few holes into the filler extension & mucking about a bit & experimenting but I don't see why it cant be done; hopefully the oil blown out the engine breather will go back into the tank. Any pressure from the engine breather that goes to the tank then vented out of the other side of the filler extension, in essence a simpleton take on H's Bullet breather. If it works out ok i'll let people on here know.

I don't know if you do FB? On there there's a closed group called British Motorcycle Mechanics, anyway on there's a guy called Claude Besson (an RE enthusiast) with a cleverly modified G engine that doesn't smoke or belch

Saying that.... theres a bloke not a million miles away in Wales.... Bullet Whisperer they call him... & he built an Asbo G (I'm not saying that the G s & Js are the same but they're in the same sort of engine family). I cant remember how Paul Henshaw tackled things when he did the G engine but i'm sure that if its like any of his other builds its pretty well good, give him a shout

best regards
Mark

[rickofkexby]

Hi Mark, thanks for that. The G and J crankcases are virtually the same as far as I can see
I was having the same thoughts about Hs modification my self. What you have described seems to make good sense so giving it serious thought. And of course you are right , If I ride the bike more often it would be less of a problem.
Anyhow, the crankcase is now rebuilt with a new bush, which took a bit of reaming, and the sump and tank seal made good, as it was before the strip. All good fun. Hoping to have it built up to take to Stanford Hall next weekend.
Thanks again for your input. All the best, Rick