1962 Norton 650SS Crankcase breather / oil tank

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Hi:

I have a few questions regarding the crankcase breather plumbing on my 1962 Norton 650SS.

The bike was purchased a few years ago. Nice and shiny on the outside, unfortunately much of the mechanicals proved to be extensively bodged, (apparently the guy who worked on it prior relied heavily on a hammer and chisel as his go to tools - and no, I am not exaggerating!). On the positive side it is a matching numbers, (home market) bike with its original 650 "18" "SS" motor. The engine has now been rebuilt, (including a set of rather impressive Jim schmidt trick lightweight pistons) and I / my mechanic are working on hooking everything back up prior to its first run.

When purchased, the crankcase breather, (located as I believe it should be, on the left rear of the crankcase) which has an approx 3/8" pipe aperture, was connected directly to an approx 1/4" pipe aperture on the top front of the oil tank. Oddly, to my mind at least, there is also a second 1/4" pipe aperture pointing down located towards the top of the rear of the oil tank, that has been blanked off. So it seems to me I would have a sort of a crankcase "suffocator"......

My questions are:

1. Is this the correct configuration?
2. Have I got the correct oil tank? I believe it is a Norton tank, but there seems to be quite a few different configurations / variants.
3. If I do have the correct oil tank, how is one supposed to manage the change in aperture diameter from approx 3/8" to 1/4"?

Thank you very much for your time and your patience with a Norton Newbie.

Kind Regards,

James
 
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To quote Roy Bacon:
'In general, both the 88ss and 650ss were both fitted with the standard 650 tank for 1962, but some had a modified tank with a froth tower at the top. With this arrangement, the engine breather was connected to the top of the tank and the lower was vented to feed any mist to the rear chain.'
 

texasSlick

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The size difference is of little or no matter as to flow of gasses to the oil tank. You need to find, or conjure up, an adapter. One possibility is to fit a sleeve over the inlet tube to the oil tank, to bring the O.D. up to the 3/8" size.

I am not completely familiar with the pre-Atlas breather configurations, but my guess the blanked off tube is for venting the oil tank to either atmosphere, or, as in the Atlas, to the chain-guard to get some lubrication to the rear chain. In any event, you must vent the oil tank in some way.

Slick

Edit: I see EstuaryBoy beat me to the 'Enter' key. From your description, I do not think you have the froth tower. A picture of an oil tank having the froth tower is in this link:
 
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I purchased my 10,000 mile old 1962 650 ss from the first owner so I know it's as it left the factory. As far as I remember, the breather from the inlet rocker cover goes to the oil tank & the pipe from the rear of the crank case goes to atmosphere. I will check this tomorrow when I'm back in the workshop & report back.

Martyn.
 
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The size difference is of little or no matter as to flow of gasses to the oil tank. You need to find, or conjure up, an adapter. One possibility is to fit a sleeve over the inlet tube to the oil tank, to bring the O.D. up to the 3/8" size.

I am not completely familiar with the pre-Atlas breather configurations, but my guess the blanked off tube is for venting the oil tank to either atmosphere, or, as in the Atlas, to the chain-guard to get some lubrication to the rear chain. In any event, you must vent the oil tank in some way.

Slick

Edit: I see EstuaryBoy beat me to the 'Enter' key. From your description, I do not think you have the froth tower. A picture of an oil tank having the froth tower is in this link:
 
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If it was my bike, I would have obtained an oil tank with a froth tower to upgrade it.
 

texasSlick

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If it was my bike, I would have obtained an oil tank with a froth tower to upgrade it.

Early Dommies have a tool tray that will not allow the froth tower to fit. It may be possible to upgrading to an Atlas tool tray, and thus fit an oil tank with a froth tower.

Heck, anything is possible with enough kilobucks.

Slick
 
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I purchased my 10,000 mile old 1962 650 ss from the first owner so I know it's as it left the factory. As far as I remember, the breather from the inlet rocker cover goes to the oil tank & the pipe from the rear of the crank case goes to atmosphere. I will check this tomorrow when I'm back in the workshop & report back.

Martyn.
Sorry for the delayed response. What I said above is correct. This is how it would have left Bracebridge Street. The later bikes didn't have the inlet rocker cover breather & the engine breather went to one of the tubes on the froth tower. This was a much better solution in my opinion, preventing the odd oily splodge on the driveway.
 
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Hi Martyn:

Thank you!

Any chance of a picture or two? I can give you an email address if you like.

"Matchless"... I also have a 1959 AJS model 31 deluxe. Lovely bike that has kept me on two wheels while waiting to get the Norton back on the road.

Cheers,

James
 
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1. Is this the correct configuration?

A 61 manxman has only one tube that enters through the tank skin
yours seems to be a later slimline tank with two tubes.
The intake breather is actually a joke IMO
My 63 atlas has the tower/top hat with 2 tubes.
 
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Thank you DynoDave, yours and the other replies have been incredibly helpful. At this point I think I will run the engine for the first time with the existing tank and see what happens, (breather attached to the front tube). It will be interesting to see how much oil (and or mist) comes out of the second tube. If tests are unsatisfactory, at least I now know what a tank with a froth tower looks like, so I can track one down if needed, (I think I have the later (narrower front on the oil tank side) tool tray that has room for a froth tower tank.

Cheers,

James
 
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Thank you DynoDave, yours and the other replies have been incredibly helpful. At this point I think I will run the engine for the first time with the existing tank and see what happens, (breather attached to the front tube). It will be interesting to see how much oil (and or mist) comes out of the second tube. If tests are unsatisfactory, at least I now know what a tank with a froth tower looks like, so I can track one down if needed, (I think I have the later (narrower front on the oil tank side) tool tray that has room for a froth tower tank.

Cheers,

James
You will discover the later tanks no longer have the attached shield for ? air cleaner, I believe I saw it on your pix. I would swap you for a later style tank.
dynodave small d
Northern New England Norton Owners NNENO
 
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