Oil valve solution to oil falling to crankcase

Hello,

As new on Norton I received some advice about Norton engines traditional problems from an experienced fellow and I would like you to tell me if is true and eventually how to solve it:
He told me every Norton engine tends to empty the oil tank when the bike is stored for sometime, it seems the oil falls into the crankcase and this can be a potential cause of troubles due to excess of oil pressure when starting the engine. Is it so?

I am restoring an MK3 and I would like to know if also my bike engine may suffer this problem. My friend installed a special valve that manually closes the oil hose going to the crankcase and also cuts ignition to avoid starting the engine without oil feed. It is this solution necessary and good?

Why not eliminate the source of the wet-sumping instead of applying band-aids.? My engine is down so I'm taking the opportunity to send my timing cover and oil pump to AMR for the cover/pump mods as well as the PRV mod. $100 for both.

 
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Why not eliminate the source of the wet-sumping instead of applying band-aids.? My engine is down so I'm taking the opportunity to send my timing cover and oil pump to AMR for the cover/pump mods as well as the PRV mod. $100 for both.


Help, yes :) Eliminate, no :(
 
If you go with AMR be sure and do all the mods. I've had 4 bikes done. One is perfect, doesn't lose any. Two were sort of slow drainers, let them set for a few months they would be down considerably but still enought left that I was comfortable starting them especially since they had reed valves in the breather lines and return was really fast. Jury is still out on the last one as I'm just breaking it in. It drains in a few days and I haven't fitted a breather valve on it, so I just drain the sump each time and reuse the oil.
 
If you go with AMR be sure and do all the mods. I've had 4 bikes done. One is perfect, doesn't lose any. Two were sort of slow drainers, let them set for a few months they would be down considerably but still enought left that I was comfortable starting them especially since they had reed valves in the breather lines and return was really fast. Jury is still out on the last one as I'm just breaking it in. It drains in a few days and I haven't fitted a breather valve on it, so I just drain the sump each time and reuse the oil.
Yes I'm having the PRV mod done as well as the oil pump and timing cover check ball valve.
 
When racing my 850 monoshock I couldn't keep either a composite or Copper HG from leaking (long before I tried Pliobond). So out of desperation I machined a groove for thin copper wire as explained below and it worked great. You could probably change the depth and wire size and groove either the head or cylinders - what I came up with worked the first try so I never experimented further. The wire would crush after a few re-torques but it still remained proud of the surface.

Oil valve solution to oil falling to crankcase
 
I see your point. So for this useful purpose may I alternatively install this model I can get in UK?

If it works in a similar way as the NYC Reed breather I can maybe install it and also install the oil tap with cutout switch.
I fitted one of those, all I can say is I have no oil leaks, wet sumping has never caused me a problem. I will drain the sump after prolonged sitting.
I couldn’t afford the Comstock breather at the time, which I’m sure is brilliant.
 
For many here, this is captain obvious talk, but not for all:

If you had a totally sealed crankcase and it was closed up with the pistons at the top, when the pistons moved down a tremendous pressure would build in the crankcase, probably blowing out seals. Vice versa, if it was closed up with the pistons at the bottom, a tremendous negative pressure would build up as the pistons moved up which at a minimum would reduce your power and probably suck things in past the seals.

Making the crankcase open to the air which later Norton and Triumphs did only partly solved this. Earlier ones had timed breathers that breathed through the camshaft and a camshaft driven "window" that opened and closed as the cam turned. This was basically the same as having a reed valve but the passageway was too small and the timing was too abrupt which is probably why they abandoned the idea.

Automobiles had a much less but similar problem and the PCV valve was one of the first pollution controls. It returned any air escaping the crankcase to the intake manifold but prevented intake manifold fuel/air from entering the crankcase because it is a one-way valve. Using a PCV valve on a Norton does help just not as well. Many are simply a disk with no spring or a minimal one that must be oriented in a particular way to do anything - they usually plug into a rocker cover.

The three brands of reed valves I know are attached at or near the bottom of the crankcase and the reeds ensure that the valve is only open when crankcase pressure is present. This, unlike the timed breather, makes the proportional to the need at every instant. It also means that if oil is present at the reed, it will be expelled, with force, out of the crankcase and to the oil tank. It also means that there is much less likelihood of blowing a seal because pressure is not built in the crankcase even with it wet sump'ed.
 
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I fitted one of those, all I can say is I have no oil leaks, wet sumping has never caused me a problem. I will drain the sump after prolonged sitting.
I couldn’t afford the Comstock breather at the time, which I’m sure is brilliant.
Another inexpensive reed valve breather.

Oil valve solution to oil falling to crankcase


Oil valve solution to oil falling to crankcase


Oil valve solution to oil falling to crankcase
 
I’m a belt and suspenders guy so I’ve pretty much done several things to my 73 850 to solve sumping issues. I did the AMR mod 10-15 years ago, but it didn’t completely solve things. A couple years ago I called them and they told me they had an additional fix, the OPRV mod. Apparently the stock drillings short circuited the original mods they did, and the oil just flowed around the fix. This pretty much fixed things, and now I can go a month or more with no sumping at all. Then I put the brake booster in the breather pipe to solve a different problem, the pressure buildup in the crankcase. It is quite effective. It pulls enough vacuum that no oil will come out the drain when changing the oil unless you disconnect the breather line to let air in the crankcase. This is basically the same one way valve principle as the 650 Yamaha reed valve or a PCV valve, and costs maybe $5 with shipping to Alaska. I have never done the reed valve in the crankcase mod— I don’t need it, and it’s expensive. And finally, for what it’s worth, I would never put a shutoff in the oil supply line— I don’t need it, and I forget things just often enough to see a significant risk there.
 
As for fitting an oil line cut out valve, all I can say is don't ! Spend some money on the NYC mk3 sump breather (Comnoz breather) if any oil drains into the sump a few kicks will put it back into the tank.
 
Finally after considering your multiple suggestions, contacting with Andover Holland Norton and listening to his kind advice I have ordered an oil tank automatic anti wet sump valve. I will install it instead of the oil line cut out valve with switch.
 
Well, I'm losing about 400ml into the sump after a week, in spite of leaving the bike at TDC, so..
I fundamentally disagree with in-line valves on the suction side so will go the AMR route.
AMR don't offer an exchange service so they suggest I send my pump & cover during "winter".
There is no time of the year here where we can't ride so that's difficult. Maybe 3 months without riding? I don't think so.
So, next port of call.
Buy a US cover off eBay and send it to AMR.
Next - oil pump.
Steadfast sell "new" "UK made" oil pumps but not sure of origin. Anyone here bought from them and care to comment on quality?
Any other US suppliers of good oil pumps?
Cheers
 
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I’m ghetto😂 my bike sumps after a week and I pull drain plug and recycle oil to tank. It’s almost a ritual to do it now. I know it’s hard for some to bend down and so this…I’m 50 and it’s a little crampy.
I have the cheap reed valve too and it works great at relieving about 90% of my old leaks. I keep mine about 4”above the breather elbow.
 
Well, I'm losing about 400ml into the sump after a week, in spite of leaving the bike at TDC, so..
I fundamentally disagree with in-line valves on the suction side is will go the AMR route.
AMR don't offer an exchange service so they suggest I send my pump & cover during "winter".
There is no time of the year here where we can't ride so that's difficult. Maybe 3 months without riding? I don't think so.
So, next port of call.
Buy a US cover off eBay and send it to AMR.
Next - oil pump.
Steadfast sell "new" "UK made" oil pumps but not sure of origin. Anyone here bought from them and care to comment on quality?
Any other US suppliers of good oil pumps?
Cheers
Though I fundamentally disagree with your fundamental disagreement, I have heard of a user here (in USA by name of @drp) selling a new, never in use MKIII timing cover. Not sure what if any mods AMR offers for a MKIII cover, but could work out for you.
 
Well, I'm losing about 400ml into the sump after a week, in spite of leaving the bike at TDC, so..
I fundamentally disagree with in-line valves on the suction side is will go the AMR route.
AMR don't offer an exchange service so they suggest I send my pump & cover during "winter".
There is no time of the year here where we can't ride so that's difficult. Maybe 3 months without riding? I don't think so.
So, next port of call.
Buy a US cover off eBay and send it to AMR.
Next - oil pump.
Steadfast sell "new" "UK made" oil pumps but not sure of origin. Anyone here bought from them and care to comment on quality?
Any other US suppliers of good oil pumps?
Cheers
400ml sounds excessive
Have you done the usual oil pump backing plate refacing etc ?
I have a MK3 timing cover on my 750 it takes several weeks before I need to worry about it sumping
Even if it does wet sump I have a reed valve in the timing cover that stops the oil seal blowing out in the primary side crankcase when I press the starter button
It soon levels off in the oil tank
 
If the intake screen is not visible, I start it up and watch return. That's with a reed valve. If the oil intake screen is visible, I drain the sump.
 
Got what looks to be a good unused timing cover (NOS) for $150USD and a Steadfast pump for $300USD.
They're on their way to AMR for them to weave their magic.
So $550USD for the work which will yield a spare timing cover and oil pump.
I will report on a, hopefully good, difference once fitted.
Cheers
 
400ml sounds excessive
Have you done the usual oil pump backing plate refacing etc ?
I have a MK3 timing cover on my 750 it takes several weeks before I need to worry about it sumping
Even if it does wet sump I have a reed valve in the timing cover that stops the oil seal blowing out in the primary side crankcase when I press the starter button
It soon levels off in the oil tank
No I haven't checked that.
It's a cNw bike so I trust that Matt will have done that.
It was good but has got progressively worse over the past year so I suspect increased internal clearances in the pump to be the culprit.
I have the reed valve on the rear of the crankcase but am draining and pouring back into the tank to be safe and to keep an eye on volume.
On the upside I get to look at the oil, which looks to be very good (Royal Purple 10W40 - thanks @comnoz !) even after 2000 miles. Service due next week.
Cheers
 
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Hopefully one of you smart blokes will have the answer at their fingertips...
How much oil "should" be in the sump when you shut down the engine?
Cheers
 
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