Please explain the wet sump issue

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MikeM

MikeM

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Sorry, I know this is a rehash.
I know wet sumping happens after a prolonged period of sitting. Oil seeps to the bottom of the engine. Can I just pull the plugs and turn the engine over til the tank fills?
Can this also happen while the engine is running?
How to avoid, short term cure?
I am about to get my bike back with a new engine and dont want to have any issues.
Please explain and excuse my ignorance.
Thanks Mikem
 
MikeM said:
Sorry, I know this is a rehash.
I know wet sumping happens after a prolonged period of sitting. Oil seeps to the bottom of the engine. Can I just pull the plugs and turn the engine over til the tank fills?
Can this also happen while the engine is running?
How to avoid, short term cure?
I am about to get my bike back with a new engine and dont want to have any issues.
Please explain and excuse my ignorance.
Thanks Mikem
Click to expand...

Hi, you can't kick it over, it would take hours of kicking, the pump is relatively slow turning/low volume. It won't happen while running. Ride it frequently to avoid it. There is a check valve modification to the timing chest cover that is well regarded. I got lucky, my engine takes months to wet sump.
 
concours said:
MikeM said:
Sorry, I know this is a rehash.
I know wet sumping happens after a prolonged period of sitting. Oil seeps to the bottom of the engine. Can I just pull the plugs and turn the engine over til the tank fills?
Can this also happen while the engine is running?
How to avoid, short term cure?
I am about to get my bike back with a new engine and dont want to have any issues.
Please explain and excuse my ignorance.
Thanks Mikem
Click to expand...

Hi, you can't kick it over, it would take hours of kicking, the pump is relatively slow turning/low volume. It won't happen while running. Ride it frequently to avoid it. There is a check valve modification to the timing chest cover that is well regarded. I got lucky, my engine takes months to wet sump.
Click to expand...


Can you explain the timing cover valve. The builder mentioned it but of course its additional expense. Now is the time to put it in. Is it worth it? He basically told me to drain the oil and put it back in the oil tank. Sounds like a pain in the ass.
 
There are a couple of different manual valves with ignition cutouts that you can purchase. These go in the supply line and switch off the ignition when the valve is closed, turn it back on once the valve is opened, so as long as the switch work you are OK
I have a setup here that I haven't quite finished, it just uses the ignition key as the lever to turn off the valve. Once turned off the key /lever cannot be removed from the valve. So there is no wiring and no switch to pack it in.
Turn the valve back on and you get your key back, away you go. It is stupid simple but will be foolproof as long as you only use the one key, although I do always have a spare taped somewhere on the bike. I would only use the spare if I was out on a ride, away from home and lost the key. In this instance the valve would not be closed anyway, it would only get closed when in storage for more than a week or so at home.
I might get around to making a batch of these things for sale, but it could be awhile. In the meantime the switch type ones are readily available.
Glen
 
You can get one of the sump plugs with a smaller bolt in the center and drain it that way and put the oil back in the tank. Mostly just forget it unless it causes problems, which I can't think of except maybe a little smoke on startup.

Now in my experience, I let my bike sit for months at a time and with that oil in the engine, it leaks, so I put a ball valve in the feed line down by the gearbox and shut it off. Also a micro-switch to prevent starting with the valve off, you don't want to start the engine with no oil feed. Not everyone likes that, it starves the cam from oil during startup. I think it depends on how long you let it sit between rides, if you ride it regularly, don't worry about it. If not the timing cover mod will help but not stop the sumping from what I've heard. I would try it first and not worry about it unless you find there's a reason to worry about it after a while.

Dave
69S
 
MikeM said:
concours said:
MikeM said:
Sorry, I know this is a rehash.
I know wet sumping happens after a prolonged period of sitting. Oil seeps to the bottom of the engine. Can I just pull the plugs and turn the engine over til the tank fills?
Can this also happen while the engine is running?
How to avoid, short term cure?
I am about to get my bike back with a new engine and dont want to have any issues.
Please explain and excuse my ignorance.
Thanks Mikem
Click to expand...

Hi, you can't kick it over, it would take hours of kicking, the pump is relatively slow turning/low volume. It won't happen while running. Ride it frequently to avoid it. There is a check valve modification to the timing chest cover that is well regarded. I got lucky, my engine takes months to wet sump.
Click to expand...
It's a simple drill operation, spring and check ball added. I looked for the drawing, couldn't find it, but I'm sure someone else has it here.


Can you explain the timing cover valve. The builder mentioned it but of course its additional expense. Now is the time to put it in. Is it worth it? He basically told me to drain the oil and put it back in the oil tank. Sounds like a pain in the ass.
Click to expand...
 
As mentioned already, wet sump is almost completely a philosophical issue and the manner of dealing with it completely dependent on your level of understanding the fluid dynamic benefits of extra oil on start ups vs the lack of it.
So far I've heard of 3-4 crank sealing failing with the blame on too much wet sump, though wet sump start is so long a universal condition there should be almost universal reports of blown seals but there ain't. On the other hand I've read of at least a dozen ruined engine events d/t some hang up on anti-sump device but darn it they didn't have a worry about engine oil in the primary eh.
i vote put the extra expense in tiddy up the pump and leave crank near TDC on shut downs. Excessive wet sump could smoke on 1st cold start ups for 20-30 sec from the bore splash till level lowers, then can check actual oil tank level.
 
The timing chest modification involves installing a check ball and spring on the outlet of the oil pump. It is a good modification but it does not completely eliminate wet-sumping. They will still wet-sump after setting for several weeks.

As an option you could install my sump plug reed breather. It does not stop wet-sumping but it will return any excess oil in the sump to the tank in a matter of seconds after you start it. It eliminates any need to drain the sump by pulling the plug. It also helps eliminate oil leaks.

My breather will not fit if there is a crosstube that runs under the sump plug as on some 71 and earlier bikes. Jim
 
"Returns excess oil in a matter of seconds"
hehe perfect solution to a philosophical dilemma, if wet sump was damaging its by far most damaging on the first few down strokes, so might as well close the barn door after the horses left the building : )

Reminds me of old riddle joke.
What does a lemon, a baby and a boat have in common?
Baby and boat bottoms are always wet.
 
hobot said:
"Returns excess oil in a matter of seconds"
hehe perfect solution to a philosophical dilemma, if wet sump was damaging its by far most damaging on the first few down strokes, so might as well close the barn door after the horses left the building : )

Reminds me of old riddle joke.
What does a lemon, a baby and a boat have in common?
Baby and boat bottoms are always wet.
Click to expand...


Damaging ...no. Not unless the first kick is big enough to blow the main seal from it's bore. I never drained the sump before starting a wet-sumped bike with or without a reed breather.

But it is nice when the oil gets back to the tank quickly so you don't get those clouds of blue smoke when you first start it and the oil pressure comes up right away because there is some oi in the tank to pump. Jim
 
hehe, fair nuff about your upgraded function, except I have a cream of the crop Combat and its breather hose jets wet sump back in the ole tank in a few seconds too with pencil thick stream by going straight to 2000ish and been rather pleased at lack of anything on sump magnet since changing my ways to always cold start as if breaking in a new cam. Sorry for all the worry lessor models suffer. With sealed ;paper air filter and decent rings, no smoke but a few puffs. Combats proving their 2S cam worth do suffer some hi rpm wet sump till it reaches the breather hose and crank spin jets oil on out of there way more than the little pump can.
 
So if the engine is wet-sumped, how long does it take to return the excess to the tank? That is, to establish a normal operating level in the sump - or does this never happen and the engine ends up circulating a rather large lubricant excess?
I chased oil leaks for quite a while - leaks that seemed to come from everywhere and then suddenly stop. I've recently been wondering it it's down to wet-sumping. This was manifest often in my stop-start rebuild project. I originally figured that even if the engine was sumped, it'd only take a couple of seconds (at most) to remove the excess, but now I'm not so sure.
 
MikeM said:
Sorry, I know this is a rehash.
I know wet sumping happens after a prolonged period of sitting. Oil seeps to the bottom of the engine. Can I just pull the plugs and turn the engine over til the tank fills?
Can this also happen while the engine is running?
How to avoid, short term cure?
I am about to get my bike back with a new engine and dont want to have any issues.
Please explain and excuse my ignorance.
Thanks Mikem
Click to expand...

Get used to how much you drain from the sump over a set period. I know if I leave my bike for several weeks, a couple of minutes to drain 2 1/2 quarts or litres is no big deal. Its a Commando, right ? I would much rather drain the sump occasionally than add a valve upstream.
 
hobot said:
As mentioned already, wet sump is almost completely a philosophical issue and the manner of dealing with it completely dependent on your level of understanding the fluid dynamic benefits of extra oil on start ups vs the lack of it.
So far I've heard of 3-4 crank sealing failing with the blame on too much wet sump, though wet sump start is so long a universal condition there should be almost universal reports of blown seals but there ain't. On the other hand I've read of at least a dozen ruined engine events d/t some hang up on anti-sump device but darn it they didn't have a worry about engine oil in the primary eh.
i vote put the extra expense in tiddy up the pump and leave crank near TDC on shut downs. Excessive wet sump could smoke on 1st cold start ups for 20-30 sec from the bore splash till level lowers, then can check actual oil tank level.
Click to expand...

A bit of a hijack here and i do respect Hobot's experience (thou i might not understand some of it) but how would leaving crank on TDC help with wet sumping......... I have heard from older wiser persons than me to leave "stored" cycles on TDC.. I assummed that it was to protect the majority of cylinder wall from atmosphere etc (corrosion). How does this practice assist/reduce wet sumping, if it actually does??
 
hehe for over night to a week or so leaving at TDC makes oil drain have to climb a bit higher to leak out the rod shells so tends to stifle wet sump some but longer than that also protects bores as you state. Btw for the newbies there are a handful of tales of brand new ruined engines after turning engine to prime it with oil for initial start and IIRC comnoz was one of those. Same thing if turning engine trying to pump down sump below cam surf rpm, do not do it. As I've found and comnoz backs up, there is no damage from wet sump but it could reveal a weak install of crank seal is all. Wet sump can not hydraulic lock Nortons either even if engine was sunk in a barrel of oil, unless chambers filled fully too. Like a warrior that don't draw his sword w/o also drawing blood, don't start up and shut down till full engine temp reached and held at some decent oil surfing rpm, in order to lay down the nano layer of ZAPP, which only happens on surfaces over boiling temps, so some protection remains for next few slow rpm rub off turns to fire up and rev up...

Past Peel had oil tank sight and drain tube to monitor wet sump drain and total oil remaining. Oil changes were tool-less and mess-less and essentially un-attended too. Next Peel gets same handy dandy feature.
 
davamb said:
So if the engine is wet-sumped, how long does it take to return the excess to the tank? That is, to establish a normal operating level in the sump - or does this never happen and the engine ends up circulating a rather large lubricant excess?
I chased oil leaks for quite a while - leaks that seemed to come from everywhere and then suddenly stop. I've recently been wondering it it's down to wet-sumping. This was manifest often in my stop-start rebuild project. I originally figured that even if the engine was sumped, it'd only take a couple of seconds (at most) to remove the excess, but now I'm not so sure.
Click to expand...

Without my reed breather it can take several minutes for the scavenge pump to catch up and get the level in the engine back to normal. During the time the oil is deep enough to be thrown by the crank there will be smoke from the exhaust because the cylinder walls will be flooded with oil.

Of course enough oil will be returned to the oil tank to restore oil pressure sooner than that. Jim
 
Say What, several minutes to pump down the sump, ugh, Maybe if a quart.5 in sump at cam/lifer chewing warm up idle, but not if kept in cam surf rpm. Can't hydraulic lock, ain't any mechanical damage risk, a few rare crank seal failures but lots of anti-wet sump device failures, seems mis construed concepts to me. At least that's my rationale tobe lazy undisplined wet sump non-worry wart.
 
Hehe i reread it Mike, ugh, so I dare ya to restate in plain English. Do not reincarnate back with scramble brain karma.
 
So as a Norton newbie, why not a manual valve in the oil tank return line to hold the oil in the tank? Close it when parking the bike and open it before starting.
Seems simple. Am I way off base here? My new engine comes home in few weeks. I dont want to trash it right out of the box.
MikeM
 
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