Wet sumping - better to leave it?

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jseng1

jseng1

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I know of several people who have blown up their motors after installing various anti wet sumping valves and I recently heard from someone who did just that to their show winning Norton. I've never experienced any damage from wet sumping personally. I've heard concern from people that see the oil tank outlet filter gauze exposed but my personal view is that if the sump is full of oil then the crank shell bearings are going to get oil on start up through the sides of the rods dipping into oil and the oil pressure is going to be there in seconds if not sooner from oil left in the oil pump and lines and oil returning to the tank is going to recycle first thing.

It takes weeks for wet sump to occur if you tighten up the oil pump by lapping the body and that's good enough for me.

The only problem I've ever had is from overfilling the oil tank by topping it up when oil had already drained into the sump. After that one mistake I never repeated it.

So what's the big deal?
 
<Sigh>

Truly, there's no excuse for blowing up your bike unless you're an idiot. If you forget to turn the valve on, you're an idiot. If you use a valve that can fail, you're an idiot. If you have a valve and don't monitor oil pressure, you're an idiot.

I seized my engine once because I let the oil tank run dry. Yes, I'm an idiot. Knowing and accepting that I'm an idiot, I will not use a valve in my oil line.

I replaced the oil pump on my 850 with a new one and it still wet sumps. Starting the engine weekly is enough to keep that under control. At the end of the riding season I drain the tank and put a sign on the seat, "No Oil!"

Works for me.
 
Wet sumping - better to leave it?
 
I have experienced a significant problem due to wet sumping

and that is sump oil upon startup being forced through the main seal and into the primary, regardless of how often I replace the seal

excess buildup of oil in the primary leads to contaminated clutch plates and also quite possible clutch slipping

for whatever reason my bike will drain a pretty fair amount of oil in the sump in a matter of days and not weeks

you can get down on your hands and knees and remove the oil drain bolt under the engine

or you can install a "safe" valve type method of limiting the amount of oil to drain from the tank down
 
maylar said:
<Sigh>

Truly, there's no excuse for blowing up your bike unless you're an idiot. If you forget to turn the valve on, you're an idiot. If you use a valve that can fail, you're an idiot. If you have a valve and don't monitor oil pressure, you're an idiot.

I seized my engine once because I let the oil tank run dry. Yes, I'm an idiot. Knowing and accepting that I'm an idiot, I will not use a valve in my oil line.
Click to expand...

Trouble is, we are all idiots.
 
If you don't resolve the wetsumping at least give a place for the oil to go that's not the main seal. This is where the reed valve comes into play, but make sure it's directly connected to the crankcase (either via the sump plug on the bottom or off the backside. Timing side doesn't help.

That being said my brother has the AMR fix which includes the oil pressure release valve update and seems to have pretty good luck. He's also running the Reed Breather Kit from NYC Norton.

The sump reed valve that I have is from Jim. My brother has the NYC Norton one. Both excellent products but the only current source is from NYC Norton.

NYC Norton Reed Breather Kit

Wet sumping - better to leave it?
 
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sump oil upon startup being forced through the main seal and into the primary
I have a reed valve bolted to the rear of my crankcase on my 850 engine. The moment the engine starts it is splashing oil to my cam. The reed valve extracts the oil back to the oil tank in about thirty seconds then my sump is clear. I've put over +50k on that engine after the rebuild and I don't have seals that weep through the primary.
 
CanukNortonNut said:
sump oil upon startup being forced through the main seal and into the primary
I have a reed valve bolted to the rear of my crankcase on my 850 engine. The moment the engine starts it is splashing oil to my cam. The reed valve extracts the oil back to the oil tank in about thirty seconds then my sump is clear. I've put over +50k on that engine after the rebuild and I don't have seals that weep through the primary.
Click to expand...

I think you (like me) have successfully mitigated wetsumping to a degree with the reed valves. That being said if you have a full sump you may have a heck of a time kicking it over fast enough to even get it started. At least I do.

Which is why I want to prevent it in the first place. I suspect, like most thing Norton did, they were experimenting and along the way managed to mess up the Norton engine with the Commando more than help it. The engine worked pretty good for a long time so maybe they got some "hot shot kids" who thought they knew better...
 
Timing cover spring/ball mod, oil pumps machined for x-rings (thanks Kommando!), and regular servicing of the oil pump itself. I always have one pump on the bench that's ready to go in when the cover is off, I then recondition the other to have at the ready and so on. Comnoz rear case breather, and a sump plug with a 9/16 drain bolt just for end of season draining. I don't really think about wet sumping all that much anymore.

What I will never do is put any sort of mechanical device in the feed line, switched or otherwise. Humans have yet to invent a truly "human proof" system of any sort.
 
Yup a full sump it takes about 7-8 kicks on cold frosty spring morning but once it fires I check the oil tank for return flow. (good Idea on any engine rebuild or first startup if you lay your bike for the winter). but after that I ride my bike regular enough to not worry about the wet sump issue. You could drain the engine case at the beginning of the season if you have a hard starting bike. I agree with you that the reed valve must be low in the engine if you want to clear the sump.
 
maylar said:
<Sigh>

Truly, there's no excuse for blowing up your bike unless you're an idiot. If you forget to turn the valve on, you're an idiot. If you use a valve that can fail, you're an idiot. If you have a valve and don't monitor oil pressure, you're an idiot.

I seized my engine once because I let the oil tank run dry. Yes, I'm an idiot. Knowing and accepting that I'm an idiot, I will not use a valve in my oil line.

I replaced the oil pump on my 850 with a new one and it still wet sumps. Starting the engine weekly is enough to keep that under control. At the end of the riding season I drain the tank and put a sign on the seat, "No Oil!"

Works for me.
Click to expand...
Well then I'm an idiot too! After my motor blew up I ditched the one way valve, had AMR re-do the timing cover and install seals in the oil pump. My Norton is wet sump free. It can sit unused for two months and there is minimal loss of oil level in the tank.
Ride On
Dave
 
Don't even like turn indicators on mine so why should I be tempted by suicidal gadgets? My wet sump issue is very slow anyway...... 1/2 pt. per month, so it just gets kicked and started.
 
CanukNortonNut said:
Yup a full sump it takes about 7-8 kicks on cold frosty spring morning but once it fires I check the oil tank for return flow. (good Idea on any engine rebuild or first startup if you lay your bike for the winter). but after that I ride my bike regular enough to not worry about the wet sump issue. You could drain the engine case at the beginning of the season if you have a hard starting bike. I agree with you that the reed valve must be low in the engine if you want to clear the sump.
Click to expand...

I'm not sure if it needs to be low as the pressure will push it out even if it's on the back of the crankcase.

 
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