Is this excessive wet sumping?

marshg246 said:
So, sorry, he either has no clue what he's talking about, he is senile, or you've misunderstood him.

Maybe it's a good way for him to get engine work to do - install a check valve - damage the engine and get paid to repair it :)
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This wasn't called for.

The old-timer is not senile, he has earned my respect, not just for his vast amount of knowledge but for his values in life. People do not stay in business for 62 years treating customers as you have indicated by this reply.
 
marshg246 said:
Triumph Twins cannot wet sump. The BSA singles/twins I'm aware of and BSA/Triumph triples don't wet sump unless the anti-wet sump device is not working. I have no idea about the non-British bikes. That leaves Norton. All stock Commandos prior to MK3 wet-sump and there are absolutely things you can do to reduce it on a stock bike and there are non-destructive things you can do greatly reduce or prevent it (AMR or MK3 timing cover). Also, a fail-safe oil shutoff with ignition interlock will prevent it assuming you remember to close it - however, just because it has a switch does not mean that the switch cannot fail so the "fail-safe" part is important.

So, sorry, he either has no clue what he's talking about, he is senile, or you've misunderstood him. This year alone I've rebuilt two engines damaged by feed line check valves! BTW, the workshop manual tells you how to service the pump!

Maybe it's a good way for him to get engine work to do - install a check valve - damage the engine and get paid to repair it :)
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I have heard of triumph twins wet sumping
I've never experienced it myself
 
Triumph twins use a plunger pump and by design it rarely wet sumps. However, a piece of crud can get under one of the plunger balls and cause it to wet sump. Happens very rarely and easy to fix by removing and cleaning the pump. The Trident and BSA Rocket use a rotor pump and are prone to wet sumping even with a check ball on the inlet side. My Trident was worse than my Nortons. My BSA A65 was also bad until I replaced the pump with one made by SRM.
 
10drum said:
This wasn't called for.

The old-timer is not senile, he has earned my respect, not just for his vast amount of knowledge but for his values in life. People do not stay in business for 62 years treating customers as you have indicated by this reply.
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I agree that it's not necessary to speculate some sort of mental defect or intentional misinformation on the part of the old timer, But your old friend has missed a significant design flaw in parallel twins that is cured by the addition of a reed valve.

Back in the day, I remember a certain Norton builder who used to say that all the Norton engine builders who couldn't build a leak free commando were incompetent. This was long before there were any reed valve modifications on commandos. I rebuilt my engine back then and I always had small leaks, usually at the tachometer cable. My friend Paul also had a commando that this "no leak" guy built for him and it was pretty leak free, so clearly that guy had good chemicals to seal a commando engine up as well as it could be done, but without a reed valve, eventually that crankcase pressure will cause his bike to leak too. The reed valve which came along sometime after norton commando production ended, was the design solution to have Nortons that don't leak....

For your old timer not to know how significant a reed valve is to a norton commando (or any parallel twin) is a huge hole in his knowledge base because as I stated above, crankcase pressure is a huge flaw of the original parallel twin design that got worse as the engine displacement grew larger and larger. The best correction to parallel twin crankcase pressure are reed valves. Every parallel twin expert knows that.... and it should be right at the top of the list to look for and do if your bike doesn't have one...
 
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Triumph twin pumps can leak oil if worn between the plunger and body.

Is this excessive wet sumping?
 
marshg246 said:
Yes, of course, worn out, broken, or defective parts can fail to do their job correctly. Damned if I do, damned if I don't. Say too much and nit picked to death. Say too little and the attacks begin. I've worn out my welcome in this thread - I'm, out.
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Theoretically, all pumps should leak a little as there has to be some clearance between the parts and to keep the parts lubricated.
 
marshg246 said:
Also not called for you continuing to diss everyone here providing correct info. As others have said/implied, he is simply wrong.
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I challenge you to reply to any comment I have made on this thread where I have dissed anyone.

I just asked, "Is this excessive wet sumping?" Most have given some very helpful and thought provoking replies, I appreciate all of them.

I have only quoted what an old friend of mine has told me, I have also indicated that I do not necessarily agree with his recommendation.
 
o0norton0o said:
I agree that it's not necessary to speculate some sort of mental defect or intentional misinformation on the part of the old timer, But your old friend has missed a significant design flaw in parallel twins that is cured by the addition of a reed valve.

Back in the day, I remember a certain Norton builder who used to say that all the Norton engine builders who couldn't build a leak free commando were incompetent. This was long before there were any reed valve modifications on commandos. I rebuilt my engine back then and I always had small leaks, usually at the tachometer cable. My friend Paul also had a commando that this "no leak" guy built for him and it was pretty leak free, so clearly that guy had good chemicals to seal a commando engine up as well as it could be done, but without a reed valve, eventually that crankcase pressure will cause his bike to leak too. The reed valve which came along sometime after norton commando production ended, was the design solution to have Nortons that don't leak....

For your old timer not to know how significant a reed valve is to a norton commando (or any parallel twin) is a huge hole in his knowledge base because as I stated above, crankcase pressure is a huge flaw of the original parallel twin design that got worse as the engine displacement grew larger and larger. The best correction to parallel twin crankcase pressure are reed valves. Every parallel twin expert knows that.... and it should be right at the top of the list to look for and do if your bike doesn't have one...
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Most of us here on this forum as well as the Triumph forum, airhead forum, brit bike forum, etc are riding and working on these wonderful old machines as a hobby. We share our experiences. The true motorcycle mechanics who do this for a living may not bother with these forums. The "old timers" couldn't give two shakes about siting down in front of a computer and trying to look intelligent to other forum members. These "old timers" are becoming extinct, so I listen to any who are willing to share their knowledge. I will never get on here and bad mouth anyone with 60+years of experience, I don't care how intelligent I think I am.
 
Commando owners shun AWS valves on the feed line. Velocette owners get one fitted from the factory and the bikes hold up for 80+ years. I've seen Velo experts eviscerate new owners for fitting oil taps with ignition defeat in place of the stock check valve. Seen (and been on the receiving end of) the same eviscerations happen here from Norton guys.
Gotta do what's best for you I guess and ignore the noise.
 
Tornado said:
Commando owners shun AWS valves on the feed line. Velocette owners get one fitted from the factory and the bikes hold up for 80+ years. I've seen Velo experts eviscerate new owners for fitting oil taps with ignition defeat in place of the stock check valve. Seen (and been on the receiving end of) the same eviscerations happen here from Norton guys.
Gotta do what's best for you I guess and ignore the noise.
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I was talking to a long time velocette owner not too long ago about automatic inline anti wet sump valves
I quipped "you never hear of them failing on a velo"
Oh yes you do he replied
 
It has been mentioned in this thread about parallel twins having a significant design flaw that unavoidably creates excessive crankcase pressure. Not trying to be pedantic here but important to note that it is the 360 degree crank along with the parallel twin design that compounds the problem.
 
Richard Tool said:
It has been mentioned in this thread about parallel twins having a significant design flaw that unavoidably creates excessive crankcase pressure. Not trying to be pedantic here but important to note that it is the 360 degree crank along with the parallel twin design that compounds the problem.
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That is why a crankcase breather was part of the early design and evolved through the years
 
BERT said:
That is why a crankcase breather was part of the early design and evolved through the years
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Yes but the crankcase breather wasn't a one way breather, a reed valve stops it sucking back in to the crankcase.
 
Not Combat relevant, but I'm sitting here wondering if the timed breather on the end of cam really does suck air back in. Seem to me the holes in the discs are placed so that they only let it out of the crankcase. Next time I get my motor running I'll have to check.

Anyway what this often discussed topic needs is more cow bell.
 
BERT said:
That is why a crankcase breather was part of the early design and evolved through the years
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Or maybe it devolved as model years ensued... I have a 70 commando with the timing disc incorporated into the camshaft. That is certainly an acknowledgement that the designers understood there was a crankcase pressure issue. I don't think just having a hose on the back of the engine on later models without a valve is an evolved solution. The reed valve is clearly the best solution that I've seen for that issue and I'm pretty sure Norton didn't develop it. It's actually pretty awesome that such a simple solution solves the crankcase pressure flaw... too bad it wasn't an original norton design...
 
I read on this forum that getting the engine on top dead center compression stroke reduces wet sumping. It works well on my combat engine. It still wet sumps but very reduced as my bike can drain the oil tank after 7 days sitting. Bump to compression stroke and maybe leaks 1 3rd over 7 days.
 
Come visit Toronto and I'll show you the aluminum weld to the right side upper crank case ( MK 111 ) where the rod smacked it on seizure. The previous owner fitted a spring and ball check valve that stuck closed . Early model valve ...since discontinued .
 
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