Anti-Sump Failure

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Not so sure that because a part fails that the design is wrong. How many times have we not seen parts break that werent supposed to. Doesnt mean that it is a poor design...it is just something that can happen. It doesnt matter what the part is or what its designed to do, sometimes they do in fact fail.

I can agree with you that the examples I gave you are certainly a bit different since you do have a lot more surface material to consider. It was just stuff that I thought of when interference fit was mentioned.

Dont know the reasons Al decided to change the design, so I cant comment on that. Al is not one to skimp on quality to save a buck....so I think you may be wrong in your assumption that he did it to save money.

Matt / CNW
 
ludwig said:
CNW said:
.. It doesnt matter what the part is or what its designed to do, sometimes they do in fact fail...
Now , if it where a Toyota part ...

Must say I don't feel very comfortable riding with the old type Miles-valve knowing there will be a newer/better type.
 
We constantly move forward and try to improve. Our bikes have evolved over the years and so have our parts. Our Brembo brake kit, triple trees, electronics, engine parts etc have all seen upgrades over time. Sometimes small changes, other times, big changes.

This does not mean that the parts were bad....we just did see a place where we could make a change to make it better.

Same with the Al Miles valve. Just because he is making a change to better the assembly doesnt mean that the older versions are bad.

Matt / CNW
 
Threaded is the correct way to keep said parts, which I believe are under pressure, together. At least some sort of mechanical fastening.

Actually since this is in the feed line to the pump it is under slight vacuum, which would tend to pull the assembly togetner, not apart. I would be concerned about the interference fit if it were in the return line which is under pressure, but not in the feed line.

However, I could see a potential problem if the interference fit is too loose and allows enough air to enter the valve and allow the oil contained below the valve to drain past the pump to the engine sump. After all it is the oil flowing past the pumt that is the actual problem. Starting the bike then relies on the pump being able to pump enough AIR to create the vacuum to open the check valve. Adding the adhesive should help prevent this.

I'll just keep my pump in good shape and drain the sump when necessary and forgo any valve. To each his own.
 
I 've had two of the valves in question come apart . I did not source them from CNW but they were the Miles design valves . One came apart within 10 minutes of installation . I'll take some of the blame for that one since I put it on an old MK 3 that I was intending to sell and it had rock hard oil lines . Now that I know it was a press fit design , I can see how my twisting of the valve during installation could have caused problems . Not too long after that episode , the one on my other bike came apart also . I plan to install an oil pressure gauge and will probably try another type of valve . I like the concept , but my experience tells me the Miles design execution leaves ALOT to be desired .

Ron
 
I had a spring loaded inline check valve. Don't know who's design it was. I used it very little once I found I had less than 2 psi of oil pressure at idle with hot oil. I'm saying less than 2 psi, it appeared the the oil pressure gauge needle had little if any deflection. I even tried cutting a few rounds from the spring. Still no oil pressure at idle. This was with a new oil pump and a fresh engine. Without the valve I had about 10 psi at idle with hot oil. Threw that sucker under the bench. I had AMR do the MKIII mod to the timing cover and modify the oil pump with "O" rings. End of wet sumping and still have 10 psi at idle. You'll never convince me that it is a good idea to have anything other than a hose in the oil pump intake side.
 
Gday Jim, OK Ive got to ask, whats the "O" ring conversion on the oil pump?
Also while Im in the questioning mood, September 98 Classic Bike issue has 21 mods listed by Les Emery to keep your Commando on the road. One of those was the enlarging of the oil galleries in the crank case to improve flow to the oil pump. Les stated no larger than 1/4 was recommended. Any thoughts? Regards FOXY
 
Foxy,

I'm not certain what the "O" ring mod entails, but here's AMR's description:

Additionally, two o-ring seals are installed inside the pump to prevent oil from passing between the feed and return sides which also can contribute to wetsumping.
 
JimC said:
I'm not certain what the "O" ring mod entails, but here's AMR's description:

Additionally, two o-ring seals are installed inside the pump to prevent oil from passing between the feed and return sides which also can contribute to wetsumping.


I've only ever heard of one O-ring being used before, not two, so the AMR mod. could be slightly different but, as far as I'm aware, this "O-ring" modification involves machining a groove in the oil pump shaft in the area between the two pump chambers to take an O-ring which then prevents the oil in the feed side of the pump from draining to the sump by leaking through to the scavenge side chamber.
 
I still think my manual shut-off valve with ignition interlock is the best remedy for wet-sumping!
Dave.
 
The area for the o rings is machined in the housing. It does help as they claim.The cover mod with the spring and ball is a mechanical way of solving the problem as the pump easily forces the ball away from the pump to allow flow to big end.When the machine is shut off the spring lightly forces the ball against the end of the pump stopping flow.The tech digest explains it.
Bruce
 
I still think my manual shut-off valve with ignition interlock is the best remedy for wet-sumping!

It also makes for one of the best possibilities for an engine failure. I'd put up with wet sumping before I ever put a shut off valve in the oil intake.
 
It also makes for one of the best possibilities for an engine failure.
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How can it JimC, I did say it has ignition interlock, ie the ignition is disabled when the valve is closed!
 
The Commando, chassis-wise a technological tour-de-force in it's time, was always known for quality componentry as compared to their competition. The later models, when equipped with less-than-stellar parts, such as the mickey-mouse Portuguese layshaft bearing, led to failures of associated systems (second gearset in that case) Whether wet-sumping is a problem worth fixing or not, adding cheaply-made stuff like the aforementioned discombobulating valve, is just asking for trouble.
 
daveparry said:
It also makes for one of the best possibilities for an engine failure.
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How can it JimC, I did say it has ignition interlock, ie the ignition is disabled when the valve is closed!

Interesting, please give an explanation and some pictures of your solution?
 
Sorry nortonspeed, can't get to the bike to talke pics at the moment, but it's an inline valve very similar to the one used on plumbing systems but with a switch attached, for details contact A.W. Dove, 322 Skip Lane, Walsall, WS5 3RA. Phone 01922 623571. (England)
Dave.
 
It would seem to be pretty easy to develop an insurance device for this, certainly easier than Toyota throttles. Mine has no load other than squeezing it together while I have seen folks have a pulling load on them, or allow them to move side to side. Safety wire would work on mine but a little bracket that holds each side would also work.
 
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