AMR Nortec Mod

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swooshdave said:
You might want to take some aspirin and lay down.
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Aspirin ain't cutting it.

I've got Cedar allergies and it's that time of year.

You do NOT want Cedar allergies, if you live in Cedar Park (basically next door to Leander, TX)
 
grandpaul said:
Aspirin ain't cutting it.

I've got Cedar allergies and it's that time of year.

You do NOT want Cedar allergies, if you live in Cedar Park (basically next door to Leander, TX)
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Try some Sudafed and Ibuprofen. I use that combo for sinus headaches. I’ll get a bad sinus headache when a High front comes in.
 
Dave,

Thanks for starting a wet sump cure thread with images, illustrations and theory. Good info here.

I fall into the idiot category with regard to wet sump cures, and other things Norton related. I have an Atlas engine turned Combat and I use a Commando timing cover. All the right modifications were made to make that possible. Sometime in the late 1980's I put the so called check ball against the oil pump solution into my timing cover. It never worked very well, but I didn't know about the OPRV mod. I'd never heard of AMR either. This thread is actually the first I've heard of the OPRV mod.

I pulled my timing cover off recently to see what everything looked like in there after the bike sat in the corner of the garage for almost 3 decades, and the ball bearing fell out into my used oil catch container. I actually thought I had removed it 27 years ago, because it was useless, and I figured it was just in the way of the oil path anyway. Oil was probably going past my OPRV, and I was not aware of it. Anywho, I did not fish the ball bearing out of the used oil container, and took the spring out of the timing cover. No more check ball. I don't have a wet sump issue anymore, but the solution I use is the dangerous ball valve in the oil feed line. Takes a little getting use to. I think of it as one more valve that needs to be opened or closed. Sort of like a third fuel petcock in my case. I always close my petcocks after a ride or running engine test, and obviously open them before starting the engine.

I hope the AMR solution works for you as well as advertised. The ball valve is an ugly addition on my Norton, and the AMR mod sounds like an elegant solution.
 
Schwany said:
Dave,

Thanks for starting a wet sump cure thread with images, illustrations and theory. Good info here.

I fall into the idiot category with regard to wet sump cures, and other things Norton related. I have an Atlas engine turned Combat and I use a Commando timing cover. All the right modifications were made to make that possible. Sometime in the late 1980's I put the so called check ball against the oil pump solution into my timing cover. It never worked very well, but I didn't know about the OPRV mod. I'd never heard of AMR either. This thread is actually the first I've heard of the OPRV mod.

I pulled my timing cover off recently to see what everything looked like in there after the bike sat in the corner of the garage for almost 3 decades, and the ball bearing fell out into my used oil catch container. I actually thought I had removed it 27 years ago, because it was useless, and I figured it was just in the way of the oil path anyway. Oil was probably going past my OPRV, and I was not aware of it. Anywho, I did not fish the ball bearing out of the used oil container, and took the spring out of the timing cover. No more check ball. I don't have a wet sump issue anymore, but the solution I use is the dangerous ball valve in the oil feed line. Takes a little getting use to. I think of it as one more valve that needs to be opened or closed. Sort of like a third fuel petcock in my case. I always close my petcocks after a ride or running engine test, and obviously open them before starting the engine.

I hope the AMR solution works for you as well as advertised. The ball valve is an ugly addition on my Norton, and the AMR mod sounds like an elegant solution.
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So did you just put a spring and ball into the timing cover? If it just fell out it probably wasn’t making a good seal.

The OPRV mid is apparently less well known.

Norton definitely tried different things during the Commando production. We sometime say that all Commandos are the same but there are definitely variations. I think they thought the Mk3 would the penultimate iteration, and it certainly had a lot of the learnings from the earlier bikes.

Still more to do on this as while LAB put together some drawings they are difficult to see so we’ll see about cleaning them up.
 
And you need to do the pump too. Otherwise the oil moves through the shafts from the feed side to the return side. I use X rings, AMR use O rings.

AMR Nortec Mod
 
swooshdave said:
So did you just put a spring and ball into the timing cover? If it just fell out it probably wasn’t making a good seal.

The OPRV mid is apparently less well known.

Norton definitely tried different things during the Commando production. We sometime say that all Commandos are the same but there are definitely variations. I think they thought the Mk3 would the penultimate iteration, and it certainly had a lot of the learnings from the earlier bikes.

Still more to do on this as while LAB put together some drawings they are difficult to see so we’ll see about cleaning them up.
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It looks to be the same ball bearing and spring setup as what is being used today. It was a popular back then, but not recommended by everybody. Some thought is wasn't such a great idea. No additional machine work was done. I did not use a countersink on the pump tube to get a perfect match to the ball or anything. The ball was captive in the pump seal I would imagine, cuz I don't know what else really kept it in place besides a little bit of spring pressure. Thinking back, I don't even know how I got it to stay aligned in there while I was installing the timing cover.

I'm thinking the ball bearing fell out because I used some light taps with a dead blow hammer to break the gasket seal and pulled the cover off in a jerky motion and tilted it down once off. I thought I had removed the check ball long ago, and didn't think it was in there. However, in all honesty, I installed it 30 years ago. The only thing I remember about it is where I lived at the time I did it, and even that isn't clear in my mind.

All that said, yeah, it's possible it was not done right.
 
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If folk think oil can back flow / leach past the PR valve external thread (or shuttle/piston) with atmospheric pressure what do you think happens when the system is pressurised via the oil pump. (besides a loss of running oil pressure)
 
Time Warp said:
If folk think oil can back flow / leach past the PR valve external thread (or shuttle/piston) with atmospheric pressure what do you think happens when the system is pressurised via the oil pump. (besides a loss of running oil pressure)
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If it was leaking there the loss of running oil pressure would be minimal.
 
Schwany said:
It looks to be the same ball bearing and spring setup as what is being used today. It was a popular back then, but not recommended by everybody. Some thought is wasn't such a great idea. No additional machine work was done. I did not use a countersink on the pump tube to get a perfect match to the ball or anything. The ball was captive in the pump seal I would imagine, cuz I don't know what else really kept it in place besides a little bit of spring pressure. Thinking back, I don't even know how I got it to stay aligned in there while I was installing the timing cover.

I'm thinking the ball bearing fell out because I used some light taps with a dead blow hammer to break the gasket seal and pulled the cover off in a jerky motion and tilted it down once off. I thought I had removed the check ball long ago, and didn't think it was in there. However, in all honesty, I installed it 30 years ago. The only thing I remember about it is where I lived at the time I did it, and even that isn't clear in my mind.

All that said, yeah, it's possible it was not done right.
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I've heard of MK 111 oil timing cover passage to check valve spring/ball never being drilled at the factory.
 
swooshdave said:
If it was leaking there the loss of running oil pressure would be minimal.
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Which would make the AMR mod at that area a waste of time and money.

If there was a 'spot it is the two or so threads forward of the timing cover drilled return to feed passage.
#
Kommando is on to it (and sent me his drawing) but I am not brave enough to machine the oil pump for seals to avoid leakage into the scavenge side (and back to the sump)
 
Schwany said:
It looks to be the same ball bearing and spring setup as what is being used today. It was a popular back then, but not recommended by everybody. Some thought is wasn't such a great idea. No additional machine work was done. I did not use a countersink on the pump tube to get a perfect match to the ball or anything. The ball was captive in the pump seal I would imagine, cuz I don't know what else really kept it in place besides a little bit of spring pressure. Thinking back, I don't even know how I got it to stay aligned in there while I was installing the timing cover.

I'm thinking the ball bearing fell out because I used some light taps with a dead blow hammer to break the gasket seal and pulled the cover off in a jerky motion and tilted it down once off. I thought I had removed the check ball long ago, and didn't think it was in there. However, in all honesty, I installed it 30 years ago. The only thing I remember about it is where I lived at the time I did it, and even that isn't clear in my mind.

All that said, yeah, it's possible it was not done right.
Click to expand...

The AMR ball and spring will normally pop out when the timing cover is removed. The spring in use, presses the ball against the port of the oil pump. When the timing cover comes off, the spring pushes the ball into empty space.

Initial assembly of the spring and ball is accomplished as follows:

Remove banjo bolt (high pressure oil tap), or blind cap bolt (low pressure top end oil feed) at the outside end of the main oil gallery.
Insert spring into hole, then ball and hold ball in place with finger.
Insert a stiff wire into the open end of the oil gallery, and while pressing ball deeper into hole, push the wire until the wire passes over the top of the ball and enters the oil gallery between the pump and crankshaft. The ball is now captive while the timing cover is mounted. When the stiff wire is removed, the ball pops onto the oil pump port.

Slick
 
swooshdave said:
So did you just put a spring and ball into the timing cover? If it just fell out it probably wasn’t making a good seal.
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There's no need for the ball (or Mk3 plunger) to make "a good seal" in the timing cover as it should be completely free to move so it is understandable if the ball falls out as texasSlick says because it is a modification of a standard timing cover so the available space for the ball and spring is limited. The Mk3 timing cover, however, has an external bulge that provides additional depth to accommodate the spring and plunger.

AMR Nortec Mod



The plunger is less likely to fall out (although it can if care isn't taken when removing/refitting the timing cover) due to its shape and, if I remember correctly, the spring also fits inside the plunger.

AMR Nortec Mod
 
L.A.B. said:
There's no need for the ball (or Mk3 plunger) to make "a good seal" in the timing cover as it should be completely free to move so it is understandable if the ball falls out as texasSlick says because it is a modification of a standard timing cover so the available space for the ball and spring is limited. The Mk3 timing cover, however, has an external bulge that provides additional depth to accommodate the spring and plunger.
AMR Nortec Mod



The plunger is less likely to fall out (although it can if care isn't taken when removing/refitting the timing cover) due to its shape and the spring also fits inside the plunger.

AMR Nortec Mod
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Notice that that picture shows the correct pump output and seal to use with a pre-MkIII engine? Something I learned out the hard way...
 
swooshdave said:
Notice that that picture shows the correct pump output and seal to use with a pre-MkIII engine? Something I learned out the hard way...
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Yes, but hanging a standard washer (not even the correct size washer) not a thin shim (as required) on a spigot barely wide enough to take the seal was asking for trouble as the slightest knock would've dislodged the seal and what obviously happened!


The outer edge of the flange is just visible behind the washer...
AMR Nortec Mod



...which suggests it is the wider Mk3 feed bush or possibly the pump was also from the wrecked Mk3...
AMR Nortec Mod



...as I doubt the pre-Mk3 feed bush would be visible.
AMR Nortec Mod
 
texasSlick said:
The AMR ball and spring will normally pop out when the timing cover is removed. The spring in use, presses the ball against the port of the oil pump. When the timing cover comes off, the spring pushes the ball into empty space.

Initial assembly of the spring and ball is accomplished as follows:

Remove banjo bolt (high pressure oil tap), or blind cap bolt (low pressure top end oil feed) at the outside end of the main oil gallery.
Insert spring into hole, then ball and hold ball in place with finger.
Insert a stiff wire into the open end of the oil gallery, and while pressing ball deeper into hole, push the wire until the wire passes over the top of the ball and enters the oil gallery between the pump and crankshaft. The ball is now captive while the timing cover is mounted. When the stiff wire is removed, the ball pops onto the oil pump port.

Slick
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Thanks Slick... Your assembly instructions jogged my memory a little. I sort of remember the fiddly part with the wire. Without knowing about the other modifications at the time, the check ball spring thing by itself wasn't a very useful long term solution in my case. If I left the bike parked for more than a month I drained the sump before starting it. I don't have to worry about that anymore with the dangerous ball valve in the oil pump feed line from the tank.

If I had installed the check ball incorrectly (just put it in there) I doubt the motor would have been very happy. I put 7K miles on that motor with check ball in there. Most of them chasing modern sport bikes around as hopeless as it was with 7-inch SLS brakes.
 
I did this modification on an Atlas motor and it has worked out well. The only downside I can see is if either the ball or spring get lost or the bike sells and the new owner has no idea of the modification, loses the spring or ball and installs the timing cover as per the manual.
How effective would it be to just do the oil pump oil seal? And are the 4 long thin screws available?
 
seattle##gs said:
I did this modification on an Atlas motor and it has worked out well. The only downside I can see is if either the ball or spring get lost or the bike sells and the new owner has no idea of the modification, loses the spring or ball and installs the timing cover as per the manual.
How effective would it be to just do the oil pump oil seal? And are the 4 long thin screws available?
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I have 3 MK111 oil pumps.
Use the stock seal system and most people don't know that the timing cover gears are a bit thicker than pre-75 models and can't be interchanged to earlier models . A fresh oil pump to timing cover seal needs to be fitted every time the cover is off , it gets crushed and cooked.
 
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