oil leak

[muskrat]

G'day Dave.
To facilitate drilling for the breather passage then blanked off at the factory. Has been known for some to remove the plug for extra breathing
Cheers

[David Tinsley]

G'day Dave.
Yep that's it. As bergs said that hole should be blanked off. Surprised you didn't have oil all over the gearbox.
Looks like you're going to take the inner cover off after all. I can't remember what size the hole is, tap a thread and screw in a grub screw with Loctite.
Cheers

Muskrat,
Well, that is a strange one. I did not get any oil from there. Glad I mentioned it now. Guessing it was machined in for manufacturing reasons. I wonder how long the plug has been missing.

[berger]

David no wonder you had problems  i took the plug out of mine for cleaning purposes i think it's 3/8ths whit if i remember correctly .

[David Tinsley]

David no wonder you had problems  i took the plug out of mine for cleaning purposes i think it's 3/8ths whit if i remember correctly .

half the "fun" on these old things is the detective work needed!
3/8 BSW, that will be fun to hunt down.
As for it adding to the problem, I would have thought it would ease it, making the engine easier to breath.

[berger]

David no it has be timed yours would of been way out of kilter sucking and blowing like a good one , but at all the wrong times and places a round bit of ally or even WOOD dowel glued in with araldite would work ,

[muskrat]

G'day Dave.
In your area. https://www.grainger.ca/en/product/SCREW-SET-SOCKET-3-8-24X3-8-PLAIN/p/UBO15083
Cheers

[JulianS]

That drilling is also timed by the revolving breather with its 2 holes. I have seen an A10 with a banjo type outlet connected to this outlet. I toyed with the idea of adding such to my A10 but it did not seem worth the trouble.

[chaterlea25]

Hi David,
Don't think the purists will agree with me but, a 3/8 UNC grub screw will fit instead of the WW one.. get an Allen grubscrew and you will be able to fit it without removing the cover.. cut Allen wrenches to provide access

John

[David Tinsley]

Hi David,
Don't think the purists will agree with me but, a 3/8 UNC grub screw will fit instead of the WW one.. get an Allen grubscrew and you will be able to fit it without removing the cover.. cut Allen wrenches to provide access

John

I would likely have to remove the cover to tap the hole, or is it already tapped?

[berger]

David it should be tapped unless it's been drilled out, the mystery is why wasn't the plug in and how long has it been like this?

[David Tinsley]

David it should be tapped unless it's been drilled out, the mystery is why wasn't the plug in and how long has it been like this?

That certainly is the mystery. I have not really ridden the bike much just up and down my road to see how it is running. No oil leaks from that area, it is quite dry.
I am going to plug it and see how things go. I dont think the lack of the plug there caused the big leak i had from the primary as it only happened on the last time I had it running last week, not before.

I am going to try and find a plug that will fit. It apparently is 3/8 BSW but I doubt I will be able to source one. The parts book does not call out that plug, logically I guess. 

[berger]

David a cut down set screw with a bit of goo will plug it or a dowel and goo. it may not be the cause of the problem but if you had air coming out of it the plug may not be there, if  it  is there it sits deep in the hole about 5 to 6 mm up and you may feel it with a bent wire, if the wire travels a lot further up to the timed breather unit it isn't there 

[sean]

That certainly is the mystery. I have not really ridden the bike much just up and down my road to see how it is running. No oil leaks from that area, it is quite dry.
I am going to plug it and see how things go. I dont think the lack of the plug there caused the big leak i had from the primary as it only happened on the last time I had it running last week, not before.

I am going to try and find a plug that will fit. It apparently is 3/8 BSW but I doubt I will be able to source one. The parts book does not call out that plug, logically I guess.

Best bet to find one around here would be a call to Mike at Wallridge motors in Lucan … likely wont have a grub screw but probably have a bolt the correct thread you could cut down and cut a slot in and screw it in with red loctite.
You wont be riding for a while in this weather , I used to leave the drain plug undone and put a tray under the bike …. Save you going through this come spring

[David Tinsley]

That certainly is the mystery. I have not really ridden the bike much just up and down my road to see how it is running. No oil leaks from that area, it is quite dry.
I am going to plug it and see how things go. I dont think the lack of the plug there caused the big leak i had from the primary as it only happened on the last time I had it running last week, not before.

I am going to try and find a plug that will fit. It apparently is 3/8 BSW but I doubt I will be able to source one. The parts book does not call out that plug, logically I guess.

Best bet to find one around here would be a call to Mike at Wallridge motors in Lucan … likely wont have a grub screw but probably have a bolt the correct thread you could cut down and cut a slot in and screw it in with red loctite.
You wont be riding for a while in this weather , I used to leave the drain plug undone and put a tray under the bike …. Save you going through this come spring

Sean
No more riding this year. We got flurries today and -2 this morning! Getting too cold to do much more work in my unheated garage as well with my cold fingers!
I do intend to leave the sump drain plug out over winter.
I was thinking of your approach. I have many bolts knocking about and will hopefully find one that will fit, cut it down and fit it. 
cheers
Dave

[groily]

I am going to try and find a plug that will fit. It apparently is 3/8 BSW but I doubt I will be able to source one. The parts book does not call out that plug, logically I guess.

An easy-to-find-there 3/8 x same 16tpi UNC bolt might work as a stopgap, especially if the thread in the case is slightly worn. (In fact, you could - carefully - run a UNC tap with a lot of grease on it up the hole to get the thread angle good for UNC. No-one would ever know, and I doubt many people would care if they happenend across it in another 50 years' time.)