Cheap & easy solution for wet sumping problem

maylar

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Hmmm… the oil is covered in belt dust, which (to my mind) would indicate it was leaking whilst running…
My end of season routine is to move the motorcycle out of the garage so that cars can go in for winter. I'm blessed to have a walk-in basement in my house, and that's where the Norton lives during winter. There were no oil dribs under the bike when I moved it to the basement. After a few months there was a puddle. I don't think the oil level in the sump gets up to the oil seal if the sump is empty (normal riding). Belt dust was everywhere when I took the pic. Oil was also leaking from one of the 3 primary case bolts. I just need to remember to drain the tank before putting the bike up.
 

Fast Eddie

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My end of season routine is to move the motorcycle out of the garage so that cars can go in for winter. I'm blessed to have a walk-in basement in my house, and that's where the Norton lives during winter. There were no oil dribs under the bike when I moved it to the basement. After a few months there was a puddle. I don't think the oil level in the sump gets up to the oil seal if the sump is empty (normal riding). Belt dust was everywhere when I took the pic. Oil was also leaking from one of the 3 primary case bolts. I just need to remember to drain the tank before putting the bike up.
All I’m saying is; you do not need to have a sump full of oil for oil to make its way out of the oil seal whilst running, the crank case is full of oil mist, and as I learnt with my T140, too much crank case pressure will force some of that oily mist past that seal quite easily.
 
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Here's what I think is the easiest, cheapest solution for the wet sumping problem which can blow your PTO mainseal by inverting the lip when firing up with too much oil in the sump (causing too much pressure against the main oil seal).

A simple 1/16" cross section oring of 1-1/16" ID fits best (some may need a different size). With the oring installed and backed up by the engine sprocket there is no where for the lip/mainseal to go but to stay where it is. The engine sprocket will prevent the main seal from dislodging from its recess and the oring prevents the oil seal lip from inverting.
<snip> I don't see any downside and if it works it could shut down a lot of needless worry. Just be sure to check the fit and return with some feedback.

Dear Jim,
Friction may become a problem. The PTO seal is static (friction arises between lip and the shaft). The O-ring will be static on the shaft I guess, and will rub all way around against the seal at a surface where there is supposed to be no mechanical contact or lube. In due course this could lead to the O-ring becoming stationary (shaft starts to rotate on the O-ring), or more likely, the O-ring may disintegrate due to shear friction of rubber to rubberized thermoplastic (or whatever the seal is made of).

I don't think there is a simple solution to the occurence of an inverted seal. I can think of a complex solution though. A taylored spacer attached to the sprocket by friction steer welding will not affect hardening of the sprocket. Width will be such that no friction between the spacer and outer surface of the seal occurs. The spacer/sprocket will now act on the seal lip as a stepped shaft. Downside of this solution is - apart from the cost - the fact that it's a taylored solution due to the tapered shaft and fabrication tolerances.

Obviously it's more desirable to prevent the occurence of hydraulic pressure by oil accumulation in the crankcase. A problem should always be fixed at its root. If the bike has en e-start, detaching the plug caps and spinning the starter for 60 seconds may be sufficient. For a bike which relies on a kick start for starting, draining or prolonged kicking for 5-10 minutes (?) with plugs removed will be necessary. Draining for re-use is not a good solution, IMHO.

-Knut
 

Lineslinger

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Using emoticons really does help with intent of comment, thats what my grandkids explained to me.
One can get in a twist easily and unnecessarily...I know this how? :rolleyes:
 
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Dear Jim,
Friction may become a problem. The PTO seal is static (friction arises between lip and the shaft). The O-ring will be static on the shaft I guess, and will rub all way around against the seal at a surface where there is supposed to be no mechanical contact or lube. In due course this could lead to the O-ring becoming stationary (shaft starts to rotate on the O-ring), or more likely, the O-ring may disintegrate due to shear friction of rubber to rubberized thermoplastic (or whatever the seal is made of).

I don't think there is a simple solution to the occurence of an inverted seal. I can think of a complex solution though. A taylored spacer attached to the sprocket by friction steer welding will not affect hardening of the sprocket. Width will be such that no friction between the spacer and outer surface of the seal occurs. The spacer/sprocket will now act on the seal lip as a stepped shaft. Downside of this solution is - apart from the cost - the fact that it's a taylored solution due to the tapered shaft and fabrication tolerances.

Obviously it's more desirable to prevent the occurence of hydraulic pressure by oil accumulation in the crankcase. A problem should always be fixed at its root. If the bike has en e-start, detaching the plug caps and spinning the starter for 60 seconds may be sufficient. For a bike which relies on a kick start for starting, draining or prolonged kicking for 5-10 minutes (?) with plugs removed will be necessary. Draining for re-use is not a good solution, IMHO.

-Knut
Knut - Primary case oil will lube and prevent wear and friction. But I think it will also work just fine on dry belt drives (like mine). Being a doubter I think you would be an excellent choise to give it a go - if there is any problem you then you could let us know and we could go from there.

There are many ways to go at it and I have considered the taylored spacer you mentioned - but it would have to be exact and fit the tapered shaft without spinning and wearing on the shaft - and since every Norton is not exactly identical this would be difficult and problematic.

Wear on the oring will only be a few thou as long as there isn't too much interference and as far as I can measure the interference was close to zero when I mocked up. I doubt there is going to be any wear other than a visible mark.

Even if there is a few thou wear it will stop when interference reaches zero.

I know I should have tested this before I spread it all over the internet but I've never had a single problem due to wet sumping after 40+ years of riding and racing. So my purpose here is to offer a solution that will keep people from installing shutoff oil valves and blowing up their motors.

I'll put one in the 1st chance I get but I'm in no hurry. Some others like the idea and they may forge ahead. Whoever trys it - just be sure there isn't too much interference. With 0 interference and .015" crank endplay I think at most its going to rub off about .005" rubber each side and there will still be plenty rubber left on both the oring and the seal. Use viton 1/16" cross section and 1-1/16 to 1-1/8" ID
 
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YING

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Knut - Primary case oil will lube and prevent wear and friction. But I think it will also work just fine on dry belt drives (like mine). Being a doubter I think you would be an excellent choise to give it a go - if there is any problem you then you could let us know and we could go from there.

There are many ways to go at it and I have considered the taylored spacer you mentioned - but it would have to be exact and fit the tapered shaft without spinning and wearing on the shaft - and since every Norton is not exactly identical this would be difficult and problematic.

Wear on the oring will only be a few thou as long as there isn't too much interference and as far as I can measure the interference was close to zero when I mocked up. I doubt there is going to be any wear other than a visible mark.

Even if there is a few thou wear it will stop when interference reaches zero.

I know I should have tested this before I spread it all over the internet but I've never had a single problem due to wet sumping after 40+ years of riding and racing. So my purpose here is to offer a solution that will keep people from installing shutoff oil valves and blowing up their motors.

I'll put one in the 1st chance I get but I'm in no hurry. Some others like the idea and they may forge ahead. Whoever trys it - just be sure there isn't too much interference. With 0 interference and .015" crank endplay I think at most its going to rub off about .005" rubber each side and there will still be plenty rubber left on both the oring and the seal. Use viton 1/16" cross section and 1-1/16 to 1-1/8" ID
Jim,
I would love to try out your o-ring suggestion as I have replaced too many main seals.Where does one search for the o-ring you like?
Thanks,Mike
 

texasSlick

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Jim,
I would love to try out your o-ring suggestion as I have replaced too many main seals.Where does one search for the o-ring you like?
Thanks,Mike

Several links here for O rings in small quantities:

 
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You can get them here in the US:

(208) 413-6377

The oring you want is viton rubber 1-1/6" ID x 1/16" cross section (IDs from 1" to 1-1/8" should also work fine).
 
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I ride the bike regularly, then drain the oil in the winter. I always drain the fuel, why not the oil???
 

ashman

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If the bike is laid up then leaving the oil in will keep all those shinny parts lubed and even better if its wet sumped the cam and everything down the bottom end will have oil all over the parts, once the bike is going to be woken up it would be a good idea to drain and replace the old oil with fresh for the next season of riding, with out any oil and a long lay up more chances of moisture getting into those areas and you don't want rust on harden parts or any parts for that matter.

Ashley
 

Mart UK

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Agree, best to have oil in. I've always understood old oil contains some moisture and is acidic from use. So have changed the oil before laying up a car or bike for the winter. My preference though, is to use the bike on good days. We do get some in the UK in the winter!
 

eo1bart

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So what is a reasonable amount of oil in the sump before being at risk of blowing the crank seal?
I just drained 18oz out of the sump on my rebuilt 850, the oil tank was filled two weeks ago and I soon will be starting the engine for the first time.
 
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So what is a reasonable amount of oil in the sump before being at risk of blowing the crank seal?
I just drained 18oz out of the sump on my rebuilt 850, the oil tank was filled two weeks ago and I soon will be starting the engine for the first time.
In spring my Norton is drained before first ride. Minutes before kick off, open your exhaust rocker covers and pour about a cup of oil. This will lubricate the lifters and the cam. Cam lubrification is critical at start up. If you have an oil pressure gauge mounted, kick start without spark plugs, up untill you see some pressure. If you don't have a gauge, about 20 kicks is sufficient to charge the main bearings and have some oil already at door step of the rockers. Crank oil seal is not bullet proof. Someday, it will start to leak, as any other seals, but you have some interest to keep away high pressure from filled sump as much as possible. Don't forget to re-torque your head after the first 20-30 miles. Have a nice break-in!
 
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So what is a reasonable amount of oil in the sump before being at risk of blowing the crank seal?
I just drained 18oz out of the sump on my rebuilt 850, the oil tank was filled two weeks ago and I soon will be starting the engine for the first time.
The important thing is not to over fill the oil tank (above the high dip stick mark) and then have all that oil drain into the sump. I keep my oil between the dipstick marks and even though its drained into the sump I have never blown a main seal. I'm not saying it can't happen and that's why I'm pushing the oring - then you can let the oil drain into the sump, restart any tdmu and no worries. You just want to be sure the oil tank refills to the proper level. If its drained all the way to the gauze then I usually remove the cap and peek inside the oil tank with a flashlight to view the oil return stream.

Another easy option is to only add a cup of oil if its all the way down to the gauze - then check the level after running a few minutes.
 

ashman

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In a few workshop/owners manuals I have read over the years about storing a bike or winter lay up is to drain any old oil and to fill with fresh oil before lay up and when its time to wake the bike up is to drain the storage oil out and replace with fresh oil that you normally run for the season, I am lucky as we ride all year round here and no winter lay ups, the only lay ups I have is when doing something else to my Norton, injury or suspension, but since owning my modern Triumphs the Norton is not clocking up the miles as it use to as its no longer my everyday ride, there would be more chances of moisture when stored in a cold climate than in a warm climate.

Ashley
 
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