wet sump solution

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A couple people contacted me recently with blown motors and sad tales about oil line shut off valves (a terrible idea).

The only real problem with wet sumping I've heard of is blowing out a main crank seal. Too much oil in the sump is going to lube the cam and the journals. Too much oil in the timing chest is going to cover the oil pump and give you a spurt on startup for the rockers and its only a few seconds before oil returns to the oil tank to begin circulation. So that brings us back to the main oil seal blowing out.

Last night I realized that an Oring between the primary sprocket and the oil seal would prevent the oil seal from blowing out. An 1/8" cross section with 1-1/8" ID should fit very well and have minimum clearance. It hasn't been tested but I can't see a downside.

Forget about those disaster prone oil shutoffs. Throw in a cheap Oring instead (use silicone or viton for exposed belt drives so they won't dry out and crack). I hope this solution checks out positive and puts this whole wetsumping issue to rest.
 

marshg246

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The only real problem with wet sumping I've heard of is blowing out a main crank seal. Too much oil in the sump is going to lube the cam and the journals. Too much oil in the timing chest is going to cover the oil pump and give you a spurt on startup for the rockers and its only a few seconds before oil returns to the oil tank to begin circulation. So that brings us back to the main oil seal blowing out.
Yes! IMHO wet sumping is a good thing if it weren't for the possibility of blowing that seal or thinking you were low on oil and adding too much before starting (what a mess that makes!)

Last night I realized that an Oring between the primary sprocket and the oil seal would prevent the oil seal from blowing out. An 1/8" cross section with 1-1/8" ID should fit very well and have minimum clearance. It hasn't been tested but I can't see a downside.
Sounds good. Do you mean that there should be some clearance? If not, what about the rubbing between the sprocket/o-ring or seal/o-ring? If so, couldn't the seal partly come out?
 
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Still left with the drag of cold oil on the flywheel, perfect excuse for an electric starter :cool:
 
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If you let the bike sit long enough for it to wet sump then why not simply drain the sump the night before your ride, my Norton takes months of sitting before the oil slowly drains down to the sump, drain the oil out while doing other checks before taking it out as you should do if your bike has sat for awhile, it don't take long to drain the sump, myself can't see what the hassle is to some, my Norton has only wet sump since I semi retired it from every day riding 6 years ago as my 1200 Thruxton is now my every day rider.

Ashley
 

storm42

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I think the biggest problem with wet sumping is when it is left long enough to empty the oil tank completely, it then can take a few seconds of running to get the oil level in the tank high enough to feed the pressure side of the pump, starving the big ends of pressure fed oil. I noticed this when I fitted an oil pressure gauge.
I have it in mind to fit banjo bolt and pipe to the crankcase drain bolt hole, and fit an electric oil pump to it to return the oil back to the tank for when the bike hasn't been used for a while.
 
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Marshg246 - I see a few thou in clearance. The seal might move a fraction but won't come out and all should still be good even if there is a tiny bit of wear. Like I said - I haven't tested it and couldn't because my seals don't blow out.

Storm 42 - I don't think there is any lack of oil at the journals when the journals are dipping into the oil and being lubed through the sides of the rods each revolution - we're talking about start up RPMs for just a few seconds without load and the oil pickup in the oil tank probably only needs a few CCs of oil to start flowing again.
 
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No need for that if oil has been sitting in the bottom of your crank case everything will be fully lubed even after start up even if sat for some time.
 

storm42

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Storm 42 - I don't think there is any lack of oil at the journals when the journals are dipping into the oil and being lubed through the sides of the rods each revolution - we're talking about start up RPMs for just a few seconds without load and the oil pickup in the oil tank probably only needs a few CCs of oil to start flowing again.
Possibly, but, when I built my motor using your rods and things, it only got used for parading and possibly only started 3 or 4 times a year, when it was used it had always wet sumped. When I built the Maney motor for my race bike, I wanted to use your rods, cam, followers etc and I stripped the rods out of the parade bike, I was surprised to see that the upper shells had worn through to the copper. I doubt the engine had done a thousand miles.

At the time I put this down to starting the high compression engine with no oil pressure because the tank had emptied, and now if the engine has wet sumped, I take the plugs out and run the motor on the starter until i see the oil has covered the filter on the feed pickup.

Of course the answer to all this is to use the bike more often.
 

Bodger

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If the bike stands long enough to wet sump what's the problem with simply draining the sump and returning the oil to the tank before startup? The excess oil sitting in the sump protects everything between starts. Probably not a bad idea to turn the engine over every once in a while just to spread the oil around. Ok now I'll go run while everyone starts throwing things at me.
 
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One problem with wet sumping not yet mentioned, is that oil will make a puddle under the bike.
Have a problem explaining to wife why the oven trays has disappeared.
 

marshg246

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If the bike stands long enough to wet sump what's the problem with simply draining the sump and returning the oil to the tank before startup? The excess oil sitting in the sump protects everything between starts. Probably not a bad idea to turn the engine over every once in a while just to spread the oil around. Ok now I'll go run while everyone starts throwing things at me.
There's nothing wrong with it per say. But at my age and condition gathering the tools and tray, getting on my knees, staying there while it drains, getting back up, pouring it back into the tank without making a mess and then cleaning up is a PITA and makes me want to forget riding the Norton and fire up one of my Triumphs.
 

Fast Eddie

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I have it in mind to fit banjo bolt and pipe to the crankcase drain bolt hole, and fit an electric oil pump to it to return the oil back to the tank for when the bike hasn't been used for a while.
That’s EXACTLY what a crank case mounted reed valve breather (cNw or NYC) does...
 
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My Norton can sit for a long time before the oil level will wet-sump sufficiently to drop the level in the tank below the feed tube so I pretty much ignore the issue. I have never had a blown seal though I guess, based on reports, it can /does happen. I have the reed valve breather, which I installed many years ago. Maybe it is the reason I have never had a blown seal...I don't know.

Re the crank "dipping" in the oil...just to clarify: the ONLY time that should ever happen is when the sump has filled with oil due to the wet-sumping, and then only on the initial start for the time it takes the pump to scavenge the excess oil in the sump. Assuming the oil pump is working properly, the crank will will never dip into (or even get very close to) the oil level in the sump during normal operation.
 
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I think the biggest problem with wet sumping is when it is left long enough to empty the oil tank completely, it then can take a few seconds of running to get the oil level in the tank high enough to feed the pressure side of the pump, starving the big ends of pressure fed oil. I noticed this when I fitted an oil pressure gauge.
I have it in mind to fit banjo bolt and pipe to the crankcase drain bolt hole, and fit an electric oil pump to it to return the oil back to the tank for when the bike hasn't been used for a while.
I’m surprised that a 60 W pump claims 5 litres/minute flow rate, but it seems to be about the going rate for other similar pumps too.

Technology has left me behind yet again!
 

storm42

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That’s EXACTLY what a crank case mounted reed valve breather (cNw or NYC) does...
You would think wouldn't you, As I was loading the van up the night before the first race this year at Cadwell, I thought I would make sure the the bike still ran. I ran it up on the starter and it fired straight away so I ran it up to temp and shut it down, whilst it cooled down I gathered the rest of the kit together .

After I loaded it into the van, I noticed oil on the ramp and driveway, turned out it had blown the crank oil seal and filled the bottom of the fairing, it had run out as it went up the ramp. The next couple of hours were not a good time to talk to me as I changed the seal with the bike in the back of the van and then cleaning the oil out of the fairing.

I have a rear crank mounted read valve breather, not CNW or NYC, but having recently seen a CNW one, I can say mine would flow more oil as the reads are bigger, the limiting factor would be the pipe.

There are a number of things that caused it, all self inflicted, apart from the initial wet sump. The bike was left a good six months between starts, I always keep the revs up a bit on startup to help the cam, I didn't drain the sump etc, As Greg said it is a PITA to drain the sump, especially when a fairing is fitted, however changing the crank seal and cleaning the fairing the night before a race meet is a lot worse.

The last time I started it, I slowly ran it up on the rollers with the plugs out.
 

storm42

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I’m surprised that a 60 W pump claims 5 litres/minute flow rate, but it seems to be about the going rate for other similar pumps too.

Technology has left me behind yet again!
Probably a Chinese 5 litres/min. some of the better pumps like the Turbowerks scavenge pumps are serious bits of kit and give more useful specs, like 5 to 15 amp drain depending on oil temp/viscosity, so 60 to 180 watts at 12 volts.

I cannot see the cheap ebay pump managing its given spec with cold oil and I cannot see it handling hot oil either.
 

Fast Eddie

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You would think wouldn't you, As I was loading the van up the night before the first race this year at Cadwell, I thought I would make sure the the bike still ran. I ran it up on the starter and it fired straight away so I ran it up to temp and shut it down, whilst it cooled down I gathered the rest of the kit together .

After I loaded it into the van, I noticed oil on the ramp and driveway, turned out it had blown the crank oil seal and filled the bottom of the fairing, it had run out as it went up the ramp. The next couple of hours were not a good time to talk to me as I changed the seal with the bike in the back of the van and then cleaning the oil out of the fairing.

I have a rear crank mounted read valve breather, not CNW or NYC, but having recently seen a CNW one, I can say mine would flow more oil as the reads are bigger, the limiting factor would be the pipe.

There are a number of things that caused it, all self inflicted, apart from the initial wet sump. The bike was left a good six months between starts, I always keep the revs up a bit on startup to help the cam, I didn't drain the sump etc, As Greg said it is a PITA to drain the sump, especially when a fairing is fitted, however changing the crank seal and cleaning the fairing the night before a race meet is a lot worse.

The last time I started it, I slowly ran it up on the rollers with the plugs out.
Yes, agreed, a crank case mounted reed valve will ‘pump’ excess oil back to the tank, but maybe it’s not sufficient protection against 6 months worth (your cases must have been full)!

Mine would have drained down to the tank gauze in that time and, as already posted by someone, I’d be worried about lack of oil and lack of oil pressure to the big ends.
But several weeks of wet sump is easily handled by the breather on mine.
 

storm42

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Yes, agreed, a crank case mounted reed valve will ‘pump’ excess oil back to the tank, but maybe it’s not sufficient protection against 6 months worth (your cases must have been full)!

Mine would have drained down to the tank gauze in that time and, as already posted by someone, I’d be worried about lack of oil and lack of oil pressure to the big ends.
But several weeks of wet sump is easily handled by the breather on mine.
They were full, I blame Covid for lack of use. :D
 
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I hate the clouds of smoke on startup of a wetsumper. All that sticky black crud getting deposited on piston top, ring grooves, combustion chamber and valves. No wonder when some of these engines come apart after a mere 10,000 miles or so look like they've been burning bunker C the whole time.
And draining the oil out then dumping it back in....what a pain just to go for a ride. I'll go ride the bike with the shutoff instead.
All kinds of theories on how great wetsumping is for the engine, but these engines aren't designed to run with sumps full of oil, even for a minute or two.

One other point, in 20 years of thrashing this subject on a few forums, I have yet to see a single engine harmed by a valve with interlock.
So really a not a destroyer of engines, just a convenient addition to the bike, if needed.
If you have one or two bikes and ride them often, and the engines wetsump slowly, then you don't need one.
If you have more bikes and some wetsump quickly, fit a manual valve with safety interlock on the wetsumpers. This will do away with oil on the floor, draining and straining out road gravel from sump oil, or chancing the blown seal and living with clouds of smoke on startup etc.

We have all read of the feed line spring and ball auto antisump valves wrecking engines.
I would not fit one of these.
Some people have had good luck with them, others have not.
Not worth the risk.

Others have fitted manual valves and then relied on memory to turn it on.
That has often ended badly.
I would not go this route either, my memory for such things has always been inadequate.

But , if needed, do fit a manual valve with ignition cut out.
Just go riding with none of the above annoyances.
You can safely ignore all of the threats of impending doom.
I'll say it again, in 20 years now, there have been zero reports of engines damaged by a manual oil shut off with ignition cut out of some sort.

Or just enjoy the smoke




Glen
 
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worntorn said:
I'll say it again, in 20 years now, there have been zero reports of engines damaged by a manual oil shut off with ignition cut out of some sort.
Or rather, you have heard zero reports, from the rather small number of riders who use such a thing.
 
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