wet sumping

hi guys
ive searched the forum on this subject and found views and experiences vary greatly so to throw it out there three questions
1 does your bike have a wet sumping problem
2 is a anti drain valve a good idea?
3 wet sumping is caused by poor clearances in the supply oil pump?
thanks in advance
cheers 8) 8)

1
Depends on what you call a problem. I don't consider it one, just an issue, maybe even a feature to some. It keeps most of the engine oiled up when not used.

2
No. Just my opinion.

3
I'm not sure, probably mostly how tight the gears fit and the end play.

Mine wet sumps in about 3 days, no matter what I do and that's with SAE50. The whole tank is in the sump in 6 weeks. I'm really thinking about putting a ball valve on the feed line with a safety switch to the ignition on it, just because it's another reason not to ride when I have to drain the sump.

Dave
69S

reed valve works (in my case).
wet sumping not a 'real' problem once you know it happens (so you know you do not have to add oil each time the level goes down...).

Wet sumping is where the oil that is supposed to stay in it's tank finds it's way slowly through the oil pump filling up the crankcase. Not a "problem", it will all pump back into the tank on startup. I fitted a spring-ball inline checkvalve to stop this and it has worked fine. My understanding is the oil must be kept clean and fresh to prevent goos and acids in oil from stopping that valve from opening as required with the oil pressure increase from sitting as opposed to running.I like Jay Leno's bike and the way the valve works ,you're not going to startup anything until it is functional and flowing. Drove for 20 years without one. Damned if you do and damned if you don't. Who said that ? You really should install the reed valve to stop oil leak issues ,yes.

you have several problems with what you stated. first one is IF there is to much oil in the crankcase you run a very high risk of pushing the crankshaft seal out. that will start to flood the primary with engine oil. Second is the spring-ball anti sump BODGE is just asking for trouble without an oil pressure gauge as it is NOT IF IT WILL FAIL TO OPEN BUT WHEN!!! all it takes is an air pocket in the oil pump and it will become an expensive lesson in hydraulics. Third it IS NOT goo and acids that cause the trouble with the anti sump BODGE it is from a poor oil pump that let's air into it that WILL cause it to loose it's prime and THAT is where the trouble lies with this piece of GARBAGE engineering.

Torontonian said:

Wet sumping is where the oil that is supposed to stay in it's tank finds it's way slowly through the oil pump filling up the crankcase. Not a "problem", it will all pump back into the tank on startup. I fitted a spring-ball inline checkalve to stop this and it has worked fine. My understanding is the oil must be kept clean and fresh to prevent goos and acids in oil from stopping that valve from opening as required with the oil pressure increase from sitting as opposed to running.I like Jay Leno's bike and the way the valve works ,you're not going to startup anything until it is functional and flowing. Drove for 20 years without one. Damned if you do and damned if you don't. Who said that ? You really should install the reed valve to stop oil leak issues ,yes.

Click to expand...

Wow ,well I guess all of us who have purchased these thingys are in BIG trouble.

if you do not have an oil pressure gauge you ARE asking for trouble. I have been around hydraulics all my life and one thing you learn is you DO NOT put ANY restriction in a suction line if the pump is not submerged in the pickup source. with out the gauge you have NO way of knowing if you have no oil pressure hence the VERY HIGHLY RECOMMENDED oil pressure gauge to go along with this BODGE.

Torontonian said:

Wow ,well I guess all of us who have purchased these thingys are in BIG trouble.

Click to expand...

macca47 said:

hi guys
ive searched the forum on this subject and found views and experiences vary greatly so to throw it out there three questions
1 does your bike have a wet sumping problem
2 is a anti drain valve a good idea?
3 wet sumping is caused by poor clearances in the supply oil pump?
thanks in advance
cheers 8) 8)

Click to expand...

1. Yes every norton twin owner has a wet sump problem it is only a matter of degree. The only ones with no problem are those who have no oil in their tank or engine.

2. It is a bandaid to compensate for a partially degraded pump. Again a matter of degree....as the pump becomes more severley degraded then you trade off a "dry" sump for an increased chance of catastrophic failure from lack of oil feed to the engine.

3 Yes. from new it will wetsump though it is ALWAYS a matter of degree. There are many rediculous old wives tails perpetuated that i won't bother to repeat. I'll leave that to others.
There are 4 leakage paths.
1. gear tip to body
2. gear to gear
3. gear end clearance to body...this is the one that fettleing can reduce leakage
4. feed cavity to scavenge cavity via the shafts.

I have designed and manufactured 2 test fixtures to test Norton twin oil pumps in both static and dynamic tests and have done several dozen 6 start and 3 start versions and as a side benefit I can test measure and calibrate the over pressure valves. Among the samples I have tested so far, there was a brand new Norton Andover pump to provide a bench mark. Just this last weekend at the NENO tech session I did a 3 start atlas and a 6 start P-11 pump.
The P-11 had a high bucks (professional?) rebuild. Then after only a short use period the engine burned up the crank and we are suspecting the oil pump was excessively degraded. The pump quality was not tested as part of the rebuild.

I have shown there is as much as 5 times the leakage through bad pumps compared to new. I have tested and verified a bad pump that was absolutely unable to keep the sump scavenged.
Eventually I will submit an article to the editor of INOA norton news...maybe he'll print it if he feel it's worthy.
regardless I'll post it on my website
http://atlanticgreen.com/
cheers
Dave
NENO president and tech advisor

Thanks, DynoDave. When can we expect rebuilt pumps to spec? (kidding)

Dave
69S

bill said:

I have been around hydraulics all my life and one thing you learn is you DO NOT put ANY restriction in a suction line...

Click to expand...

So, if not on the suction line, Windy, what's the fix??? OK, I already know the answer, but I'd like to hear it again! :wink:

If there's most an inch of oil stil in tank to feed pump for start up then just start up and give enough gas not to stall while emptying the sump over 30 sec or so. It helps, to a degree, to leave the crank throws near TDC. Its pretty rare for the ball valve add ons to fail but we've had one reported here last year and I've heard of a few on NOC and BI list over the years and a famous English builder says he's taken on handfulls of them before the new engine rebuild. A few have put manual valves in line with electric switch as fail safe. On my special I put valve in the way of kicker so can get on bike it valve handle off. How about an electric valve that runs off ignition power lead?

I believe its an old wives tale of blowing out the crank seals just starting on full sump, maybe if blipped straight to red line hehe so the cold ring blow by over whelms the seals but not d/t hydraulic oil pressure or or oil wave splash. As wet sump is so universal and blown out seals so rare I take that as evidence for my opinion and ain't blown em on my two Cdo's nor has my buddy. I was a bit surprised when I re-ringed my Combat last month to fine all its oil came out the sump plug after only 2 wks. Pump was lapped fine and best parts of spares to assemble.

I had a wet sumping problem and spoke to Mick Hemmings, I bought an anti drain valve from him and it's brilliant. The valve was daed easy to fit and it went on in about 20 minutes. Cheers, Steve

I hope he sold you an oil pressure gauge to with it!!!!!!

Steve D said:

I had a wet sumping problem and spoke to Mick Hemmings, I bought an anti drain valve from him and it's brilliant. The valve was daed easy to fit and it went on in about 20 minutes. Cheers, Steve

Click to expand...

IMHO there is three ways to approach this issue short of replacing the oil pump with a KNOWN GOOD one.( expensive and not 100%) the first is to put a check ball on the OUTLET side of the pump in the timing cover, although it is NOT 100% it WILL NEVER fail to open as it is on the pressure side WHERE IT BELONGS.I guess Norton knew better than to do this BODGE also because the MK3 has a valve on the PRESSURE side also!!!! the second is to use a mechanical shutoff valve WITH an interlock so you CANNOT start it with it closed and of course the third is to ride it more often.

quote="cmessenk"]

So, if not on the suction line, Windy, what's the fix??? OK, I already know the answer, but I'd like to hear it again! :wink:[/quote]

27 years now with one way valve

Knock off the strident fear mongering.

When I installed a spring loaded check valve in the input to the oil pump the oil pressure at idle was zero. I took it out and threw it under the bench . I even cut a few rounds off the spring before I chucked it. IMO, the only thing between the oil tank and the oil pump should be an oil line.

well thanks for the replies guys i didnt realise this was such a passionate subject :lol:
so what will i do ? i think for the time being i will drain the sump , and put it back in the tank as part of the start up procedure and monitor how bad it is [ i dont think it is too bad .] i used to a own a 69 triumph 650 that had this problem and i just lived with it . although some start ups were pretty smokey untill the oil pumped back into the tank
thanks again guys 8)

One of the things I've done over the winter is install one of Jim's reed valve breathers in my 850, which wet sumps with the best of them. I had gotten into the habit of draining and filling too but now plan to kick it through a number (??) of times to see if the new valve clears the sump enough (within a reasonable number of strokes) to not worry about starting. I know others say it shouldn't really matter to start with the sump full but it just goes against the grain somehow.

Now I'm like all scared and turning white. But will continue to run with the check valve for this season. Will rethink. Re-compute.

You should realize that there will be 4 to 6 ounces after normal drainage. It takes days to loose any appreciable amount of oil from the tank to be concerned.

You can take drain amounts at different interals (days) to determine what sort of an issue with wet sumping you have. Again, there will always be some the next day from normal drainage (head, timing chest etc).