Wet sump check valve machined into timing cover?

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998cc

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After a year of renewed Norton ownership, I have determined my "new" 850 Commando wet sumps with the best/worst of them.

After viewing threads going back to 2013, it is apparent that inline ball/spring check valves can cause more trouble than they solve. Do the same issues crop up using the ball/spring check valve machined into the timing case? I also found a thread which suggests lapping the plates of the oil pump smooth helps significantly; I can do that. Does anyone manufacture an oil pump that restricts oil seepage?

I'd rather avoid a manual valve with ignition lockout unless one could be hidden.

Thank you.

~998cc
 
After a year of renewed Norton ownership, I have determined my "new" 850 Commando wet sumps with the best/worst of them.

After viewing threads going back to 2013, it is apparent that inline ball/spring check valves can cause more trouble than they solve. Do the same issues crop up using the ball/spring check valve machined into the timing case? I also found a thread which suggests lapping the plates of the oil pump smooth helps significantly; I can do that. Does anyone manufacture an oil pump that restricts oil seepage?

I'd rather avoid a manual valve with ignition lockout unless one could be hidden.

Thank you.

~998cc
The short answer is the valve in the timing chest is on the pressure side. The manual valves are on the suction side and risk being forgotten unless they have an ignition interlock.
 
I had the modification done on my '75 inside the case and it wet sumped the entire 2 qts into the crankcase anyways- a little disappointed.
 
I had AMR of Tucson install the timing cover upgrade on my Atlas (check valve) plus they o-ring the oil pump gears. It didn't work for me either.
 
Wet sumping can be caused by many factors such as the rubber on oil pump gone to the plate on oil pump sticking proud so that it will not bolt onto the crankcase without leaving a gap. Velocette solved this problem a long time ago, but too few people understand it.
 
The short answer is the valve in the timing chest is on the pressure side. The manual valves are on the suction side and risk being forgotten unless they have an ignition interlock.

Ah, so if the mod to the timing cover is on the pressure side of the pump, the pump may still allow seepage? Perhaps the only solutions are to ride more often or drain the crankcase and refill the oil tank before each ride. Assuming the oil pump is original, is it worthwhile to replace it? Speedo shows 19,000 plus miles.

Thanks again.

~998cc
 
Never had oil pump leakage/drainback issues on the 4 Nortons I've owned in this life. Use a new conical seal and pump gasket every time the cover is off. New TC gasket too.
 
I have never had a problem with it either.

But unless you ride frequently gravity will always win and the oil will end up in the sump.

But after riding Nortons for over 45 years I have never once drained the sump before starting the engine.

Since bending a rod because the petcock leaked and the Amal ran over and hydrolocked the cylinder I have made a habit of pushing the engine through slowly one time before I try to start the engine.

This undoubtedly has helped with never loosing a main seal due to a crankcase full of oil.

But yes, A check ball in the timing cover will slow down the wet sumping a little with out causing the type of issues seen with a valve in the suction line.
 
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If an ignition cut out ball valve is not to your liking (might be possible to locate one near oil tank outlet pipe for better concealment) then I think you should look at Mr. Comstock's sump drain plug breather. It passes sump oil back up to tank when pressured by piston movement.
 
Ah, so if the mod to the timing cover is on the pressure side of the pump, the pump may still allow seepage? Perhaps the only solutions are to ride more often or drain the crankcase and refill the oil tank before each ride. Assuming the oil pump is original, is it worthwhile to replace it? Speedo shows 19,000 plus miles.

Thanks again.

~998cc
The best solution, for you and the bike, is always to ride more often. Reworking the oil pump is useful if needed. You shouldn't have to replace it at only 19k miles.
 
Riding more is a good solution for just about everything in my humble opinion.... Yep picked one up on sale at Walmart the other day.
 
Ah, so if the mod to the timing cover is on the pressure side of the pump, the pump may still allow seepage? Perhaps the only solutions are to ride more often or drain the crankcase and refill the oil tank before each ride. Assuming the oil pump is original, is it worthwhile to replace it? Speedo shows 19,000 plus miles.

Thanks again.

~998cc

A new oil pump did not cure my bike of wet sumping. Even new machines suffered from this. It's even alluded to in the rider's manual.
 
AMR timing cover mod has worked well on three bikes I have. Maybe seeps a little but not so much you can't start the engine.
 
AMR timing cover mod has worked well on three bikes I have. Maybe seeps a little but not so much you can't start the engine.

The AMR timing cover mod and the "o" ring mod to the oil pump has STOPPED my Norton from wet sumping. If it sits all winter long the oil lever stay up close to the full mark. It used to take only a week to empty the oil tank before the mods.
Ride On
Dave
 
I’m going to service my pump over the winter and have been wondering about getting the AMR mod done, but the cost of return shipping from Switzerland plus potentially customs duty puts me off. From what I understand they drill the case and introduce a spring loaded ball which rests on the conical seal. I’m wondering if it’s something I could do myself or get done locally. Does anybody have any pics they could kindly post of the modified case and oil pump ?

Or can anyone in Europe do the mod?

Cheers and Happy New Year,

cliffa.
 
I swapped mine for an 850MkIII cover as it has the mod done. I mainly bought it for the cam chain inspection cover.
I sold the original for half decent money to recover some cost.
 
I’m going to service my pump over the winter and have been wondering about getting the AMR mod done, but the cost of return shipping from Switzerland plus potentially customs duty puts me off. From what I understand they drill the case and introduce a spring loaded ball which rests on the conical seal. I’m wondering if it’s something I could do myself or get done locally. Does anybody have any pics they could kindly post of the modified case and oil pump ?

Or can anyone in Europe do the mod?

Cheers and Happy New Year,

cliffa.

I did the MOD with a vertical mill, easy to do on the timing cases with the points cover as that gives you a flat area to mount the cover onto the table that also puts the oil gallery vertical.
 
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I’m going to service my pump over the winter and have been wondering about getting the AMR mod done, but the cost of return shipping from Switzerland plus potentially customs duty puts me off. From what I understand they drill the case and introduce a spring loaded ball which rests on the conical seal. I’m wondering if it’s something I could do myself or get done locally. Does anybody have any pics they could kindly post of the modified case and oil pump ?

Or can anyone in Europe do the mod?

Cheers and Happy New Year,

cliffa.

Cliffa, here is a photo of the modified case. I pulled the trigger and had mine done. The ball and spring are smaller than the diameter of the bore. That wire you see in the bore is merely a keeper until the cover is reinstalled. Also, the conical oil pump sealing washer has been replaced by a large-ish sectioned O-ring; it seems when the engine is stopped, the ball mates up with the O-ring to make the anti-sump seal.


Wet sump check valve machined into timing cover?


Cheers!
~998cc
 

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Cliffa, here is a photo of the modified case. I pulled the trigger and had mine done. The ball and spring are smaller than the diameter of the bore. That wire you see in the bore is merely a keeper until the cover is reinstalled. Also, the conical oil pump sealing washer has been replaced by a large-ish sectioned O-ring; it seems when the engine is stopped, the ball mates up with the O-ring to make the anti-sump seal.


View attachment 14117

Cheers!
~998cc

Use a plastic zip tie to hold the spring/ball in place rather than the wire AMR sends as it will score the oil pump spigot when you press the cover down.
 
Use a plastic zip tie to hold the spring/ball in place rather than the wire AMR sends as it will score the oil pump spigot when you press the cover down.

Good thought! Will do.

~998cc
 
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