AMR Wetsumping Mod Installation Video

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swoosh,
I know you spent a lot of money to get your oil pump shown getting modified... Same with all you other lot that put your check valves in or your shutoff valve in etc.... but I am running the Jim Comstock breather valve placed in the correct position on the 1974 crankcase. This will disperse any accumulated oil that invariably will drain into the crank after a long wait...lets say.... (2 Months) after a winter rest. then kick over and back into the oil tank. Jim C. even has a video.
What is your fix done to beat that?
When I start my bike and the oil is below the screen..... I know there is oil in my crank. The moment it fires, oil flings to the most important parts namely the cam. what does your dry crank have to help???
I got oil, you do not. something to think about.
Cheers,
Tom
 
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I knew this would be controversial but that's how I feel about wet sumping...but lets have at it.

that's what this forum is about.
Cheers
All the best.!
Tom
 

APRRSV

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swoosh,
I know you spent a lot of money to get your oil pump shown getting modified... Same with all you other lot that put your check valves in or your shutoff valve in etc.... but I am running the Jim Comstock breather valve placed in the correct position on the 1974 crankcase. This will disperse any accumulated oil that invariably will drain into the crank after a long wait...lets say.... (2 Months) after a winter rest. then kick over and back into the oil tank. Jim C. even has a video.
What is your fix done to beat that?
When I start my bike and the oil is below the screen..... I know there is oil in my crank. The moment it fires, oil flings to the most important parts namely the cam. what does your dry crank have to help???
I got oil, you do not. something to think about.
Cheers,
Tom
Hi Tom,
Is the J.C. breather valve areed valve and where is the location for your 1974 (rear inner timing case?
Does J.C. still mfg. these?

Thanks,
Ed
 

fiatfan

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I´m thinking of doing the mod on the PRV, drilling a new hole and blocking the old hole in the casing. Is there any downside of that modification alone?
 

Fast Eddie

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Hi Tom,
Is the J.C. breather valve areed valve and where is the location for your 1974 (rear inner timing case?
Does J.C. still mfg. these?

Thanks,
Ed

I have a ‘74 and the breather was originally from the rear of the timing cover. Therefore I used the excellent Comnoz breather that replaces the sump filter which works brilliantly. These are available from Kenny at NYC Norton.

The alternative version of the Comnoz breather is the type that bolts to the rear of the crank case. These are available from Matt at cNw.
 

mdt-son

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I'd bee interested to know if someone offers the AMR modification in Europe?
I would have thought Holland Norton Works would, but they market another product.

-Knut
 
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I´m thinking of doing the mod on the PRV, drilling a new hole and blocking the old hole in the casing. Is there any downside of that modification alone?
Why not just remove the timing discs from the camshaft end making it free flowing, and fit a reed valve in the pipe. The holes in the camshaft are a greater surface area than the reed valves smallest hole, so that is still the constriction not the untimed camshaft breather. No need to drill a new hole or block off the old one, just need to split the cases to removed the timing discs.
 

robs ss

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I have both the cNw (rear of crankcase) on the Commando and my own (copied earlier) version for my 650ss using a jap 50cc induction reed valve (cheap as chips on ebay). Both work wonderfully in keeping things "clear" even after a couple of months of inactivity.
Using this wonderful innovation, I can't see a reason to fit a valve - inside timing case or other.
My regards to Jim Comstock! (@comnoz )
Cheers
 

Onder

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1974 with Comstock reed valve breather installed, out let goes up to the oil tank.
 

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There is another wet sump solution I'm considering that's easier and cheaper. But first I want to bounce the following assumptions off everyone.

If the oil drains into the sump down to the oil tank screen it doesn't really matter because the crank journals will dip into the oil until the oil psi builds up after a few seconds (there will probably be some leftover oil in the oil pump anyway).

Using a breather at the rear of the sump may help blow the oil into the oil tank quicker (but the sump will still be swamped the 1st few revolutions). See photo below.

The only real problem with wet sumping is the danger of blowing out the main oil seal at the PTO shaft.

Preventing the main oil seal from blowing out takes care of the problem and the excess sump oil will simply pump back into the oil tank - the same as all Nortons have been doing since the beginning.

A means of securing the oil seal should dissipate all "Norton head" worries (or not?).


A rear sump breather as shown below does empty the sump oil back to the tank more quickly - but the sump is still full of oil for a few seconds anyway so it really doesn't make much difference. The reed valve is there to reduce pressure and prevent oil leaks - it won't prevent the main oil seal from blowing out because internal pressure is still high until the sump empties (the crank is splashing into the oil) - and the reed valve breather can't empty the sump right away.
breather-750g-416x413.jpg

A
 
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@jseng1 that is not a "wet sump solution" in my opinion.

The MK3 drive side oil seal is retained by a circlip - see item 14 in the factory parts book:



All it does is moves the issue to the next week point - timing side oil seal, camshaft oil seal or tacho drive.


The AMR mod is a superb one, and is preventative - it takes what the factory executed very poorly on the MK3 timing cover, and does it right.


I personally like to look at wet sumping and engine breathing as two different issues that are addressed in two different ways.

The Comstock sump plug breather addresses the breathing issue (as does your own reed breather that you show in your post)

Jim C's benefits from evacuating a wet-sumped crankcase because it is so low down, but in my opinion only as a useful by-product.
 
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Hi Ed,
Same location as post #13. but it is Comstock's design. Nothing against JS's, just that I bought the reed valve before he came up with his version. I had to machine the surface and drill holes on the drive side crankcase half. I closed up all the ports on the timing side half and dropped the oil drain hole as per past threads that I am too lazy to find.
Cheers,
Tom

Hi Tom,
Can you tell me the location of your Comstock valve on your '74 Norton?

Thanks,
Ed
 
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I guess I was a little too harsh on the OP. He does have the check valve on the right side of the pump (pressure side) and not the suction side. Sorry Swoosh. I had a few brown pops too many last night. I just don't worry anymore with wet sumping with the set up that I have.
 
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@jseng1 that is not a "wet sump solution" in my opinion.

The MK3 drive side oil seal is retained by a circlip - see item 14 in the factory parts book:



All it does is moves the issue to the next week point - timing side oil seal, camshaft oil seal or tacho drive.


The AMR mod is a superb one, and is preventative - it takes what the factory executed very poorly on the MK3 timing cover, and does it right.


I personally like to look at wet sumping and engine breathing as two different issues that are addressed in two different ways.

The Comstock sump plug breather addresses the breathing issue (as does your own reed breather that you show in your post)

Jim C's benefits from evacuating a wet-sumped crankcase because it is so low down, but in my opinion only as a useful by-product.
I don't think securing the PTO seal will move the problem to one of the smaller seals you mentioned because those smaller seals never blow out to my knowledge (they can resist the pressure - they only wear out over time). It is not good enough to have clip for the main seal because the seal can stay in place but the lip can turn inside out. The solution is to keep it in place as well as keeping the lip from turning inside out.

Lowering the reed breather doesn't prevent the crank from slapping the flooded sump oil the first few seconds and blowing out the seal.

The only real problem is the main seal blowing out. There is no other problem as far as I know. If there is another problem - please show it to me along with some proof and photos if you can.
 
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Lineslinger

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Wet sumping issues/concerns are overrated.
I can always unscrew the drain plug if needed, but honestly the only time I drain the crankcase is once a year when I take the bike out of winter shutdown.
I'd rather put the time, work and money into rideability and performance.
 
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There was a magazine article on a matchless that wetsumped, the owner plumbed in a window washer motor into a new oil pipe from sump to tank. After any layup he turn on the pump and moved the sumped oil back into the tank. Once clear the pump was turned off and not used until the sump was full of oil again.
 
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JS,
I am using a Steve Maney Crank seal and have not seen any of the issues you are describing.
As gforce stated above with the reed valve down low, that it becomes a useful by-product. Had I not installed the reed valve were it lives now, then I would be draining the crankcase the old fashion way or risk what you are mentioning above.
Cheers,
Tom
 
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