Anti-Sump Failure

grandpaul said:

A macro shot will show the same thing - IT'S BROKEN!

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Actually a close up might show whether it separated or broke. :mrgreen:

It's not broken it has come apart.

travelerjerry said:

I've seen that type with the clear plastic and wondered how they were assembled. Appears that type are glued and didn't hold? Vibration & the downward tension of the left side of valve caused to separate?

Thought about getting one of those awhile ago, glad I got a complete metal one.

Lucky you Tim that you have a pressure guage and caught it.

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Jerry, could you say where you got the all metal one? It's hard to tell which would get you first, seizing the motor or oiling down the rear tire.

Is it possible to machine the earlier timing cover to accept the MK3 non return valve?

rustynuts said:

Is it possible to machine the earlier timing cover to accept the MK3 non return valve?

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I believe the preferred fix is the "AMR" solution for pre-MkIII timing covers. Although I have heard that this is not always 100% effective.

I see reading the Pingel drag racing catalogue where they supply a "electro fuel valve". This valve is wired so that the ignition is cut until the valve is turned on. Maybe it could be adapted to the oil system of Commandos? Its made of aircraft grade alloy with various thread sizes and a good flow rate that may (?) suit oil.
http://www.pingelonline.com/fuel_valves.htm
Cant imagine that it would be cheap though.
Just a thought?

I tend to go back to the question of "what problem does this really solve." Wetsumping? I have never experienced any problem caused by wetsumping on either Commando I owned - my '71 back in the day and the 73 I own now. Heck, I never even knew wetsumping existed until a couple of years ago. And even under the most severe situation, like all the oil from the tank draining to the sump overnight, wetsumping can't cause all your oil to exit the engine...

If everything else is in order, it takes months or years for a significant amount of oil to gravity-drain from the tank to the crankcase. If the machine sits for a long time, just be sure to pull the crank drain plug and refill the tank. Short-term, there shouldn't be enough there to be a problem. Firing it up with 2 qts in the case may lead to a bit of blow-by and oil passing the rings into the combustion chamber and any poorly-sealed joints will be revealed.

I regret to say I tried one of these, Miles, WITH an oil pressure gauge. Hard to watch a gauge at nite when at speed. Lit or not. Valve failed to open I guess. Engine shut down on the intestate. Pulled to shouler expecting my cases to be gone. Limped to relations garage and took the valve apart. Pulled the spring and ball. Put it back together and had good pressure while cold. Bottom end survived but had the whole thing gone through. To quote others, "never again".

Hey,

Spoke to Al Miles yesterday and told him about the concerns. He is going to look into it and also talk to the guy that does builds them for him. Pointed him to this forum so he could see the pictures of the damaged valve.

Personally, and I do know others have a different opinion, I feel that the valve works for what it was intended to do. Of course a strong oil pump is required but that should be checked whether or not the valve is used.

This issue in this case, the valve coming apart, is a different problem and can get rectified by a better assembly.

850cmndo said:

I regret to say I tried one of these, Miles, WITH an oil pressure gauge. Hard to watch a gauge at nite when at speed. Lit or not. Valve failed to open I guess. Engine shut down on the intestate. Pulled to shouler expecting my cases to be gone. Limped to relations garage and took the valve apart. Pulled the spring and ball. Put it back together and had good pressure while cold. Bottom end survived but had the whole thing gone through. To quote others, "never again".

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These valves dont come apart so I am not sure it was a Miles model you used. Maybe an earlier version, like the Australian one that was an all metal, 2 piece, unit. From Miles I have only seen the latest version, which is this small one with a sight glass.

Matt / Colorado Norton Works

Hi,

Just wanted to report back and tell you that I have had several conversations with Al Miles (the designer and manufacturer of the valve) in regards to the broken wet sump valve since this problem was brought to my attention. Both Al and I have had great success with the valve and have many of them out there working perfectly for several years. When this thread came up it was the first one I had seen break. Nevertheless I felt that this was reason enough to have Al look closely at the assembly to see what could be done to eliminate any possibility of it coming apart.

He has decided to do two things. Tighten up the interference fit in-between the parts (they are pressed together) and also use a glue/sealer in-betweenn the different pieces. I personally feel that this will take care of it.

I also want to mention, not that this situation wasnt serious, that the failure of this valve was the assembly itself. It was not the function of it that failed. I also feel that it was a isolated incident considering how many valves are out there working great. I cant say why it came apart but it certainly did and even though there are some possibilites, it would really just be speculation. Unfortunately there is always a possibility of a part failing, I dont care what it is and how careful the manufacturer is building it. No excuse by any means....just somehting we do have to look at when producing parts.

I do want to apologize to Tim for his problems and the results of the valve coming apart. Many of us that are involved in this business take it very personally when there are issues since we just want our customers to enjoy and appreciate these great machines.

CNW will keep using this valve on all the machines we build since I do trust the valve and the performance of it.

Matt / Colorado Norton Works

Why not add a metal "c-clip" that fits around both ends of the valve and applies pressure from each end towards the center. Could even be a "c" with a screw/nut like some types of hose clamps.

mike996 said:

Why not add a metal "c-clip" that fits around both ends of the valve and applies pressure from each end towards the center. Could even be a "c" with a screw/nut like some types of hose clamps.

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I dont think that valve was assembled poorly before and the additional improvements will make it that much stronger.

Matt / CNW

I've used one of the CNW valves for over three years now with no problems. I do keep an extra piece of copper tube in my tool kit to splice the hoses together if It does fail while I'm out on a ride. CNW does seem to not only make good quallity items but they also seem to care about their customers. These old nortons not only have good people riding them they also have good people making us parts. Thanks guys.

CNW said:

He has decided to do two things. Tighten up the interference fit in-between the parts (they are pressed together) and also use a glue/sealer in-betweenn the different pieces. I personally feel that this will take care of it.

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Wow, an interference fit only? I mean I'm no engineer but such a part you don't ever want coming apart.

Maybe I'll put a thin line of epoxy around mine? Just in case

CNW said:

Hi,

I do want to apologize to Tim for his problems and the results of the valve coming apart. Many of us that are involved in this business take it very personally when there are issues since we just want our customers to enjoy and appreciate these great machines.

Matt / Colorado Norton Works

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Matt
No apology necessary. Mechanical devices break, that's just part of this business. After looking at the valve very closely, I think Al Miles has an acceptable solution in tightening the fit and using some adhesive. Nothing broke, it just came apart. I still recommend an oil pressure gauge, but recognize that they could also fail. Anyway, thanks for your response. I sent the valve back to the vendor I purchased it from, and he has offered to refund the purchase price. There are a lot of nice people out there.
Tim

swooshdave said:

CNW said:

He has decided to do two things. Tighten up the interference fit in-between the parts (they are pressed together) and also use a glue/sealer in-betweenn the different pieces. I personally feel that this will take care of it.

Click to expand...

Wow, an interference fit only? I mean I'm no engineer but such a part you don't ever want coming apart.

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An interference fit can be extremely strong and used in many applications. I am certainly not an engineer either but when I think of all the parts on these machines that are assembled with an interference fit then you have to consider that this is probably a very effective way to make things stay together. Think of all the bushings, bearings, races, valve guides and more.

When Al Miles initially designed this valve that we are currently using he had male and female threads on the different parts. He changed that at some point in favor of the press fit. I am sure he wouldnt have done this unless he was confident it would be just as strong or stronger.

Matt / CNW

CNW said:

swooshdave said:

CNW said:

He has decided to do two things. Tighten up the interference fit in-between the parts (they are pressed together) and also use a glue/sealer in-betweenn the different pieces. I personally feel that this will take care of it.

Click to expand...

Wow, an interference fit only? I mean I'm no engineer but such a part you don't ever want coming apart.

Click to expand...

An interference fit can be extremely strong and used in many applications. I am certainly not an engineer either but when I think of all the parts on these machines that are assembled with an interference fit then you have to consider that this is probably a very effective way to make things stay together. Think of all the bushings, bearings, races, valve guides and more.

When Al Miles initially designed this valve that we are currently using he had male and female threads on the different parts. He changed that at some point in favor of the press fit. I am sure he wouldnt have done this unless he was confident it would be just as strong or stronger.

Matt / CNW

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Think of the examples you use of interference fit, in all of the cases it's substantial amount of material holding the other part. In the case of the inline oil valve there isn't the material to support the interference fit. He changed from threaded to press-fit to make it cheaper to manufacture. Threaded is the correct way to keep said parts, which I believe are under pressure, together. At least some sort of mechanical fastening.

He may have been confident but apparently he was wrong. Happens to all of us.

swooshdave said:

He may have been confident but apparently he was wrong. Happens to all of us.

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It happened to NASA more than once.

I honestly don't think anything is unbreakable or failure proof. Shit happens.