Anti wet sump valve sieze (2015)

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850 crank must be split to regrind as flywheel overhangs big ends but 750 does not. But given the fact the shells have chewed up the rod there may be shrapnel inside the crank as it tends to get everywhere so wouldn't hurt to split an clean it out.
I had my crank reground by Mick Hemmings and reassembled as i wanted to make sure the radius was done correctly (see resent post by some unfortunate member who's crank was ruined) and it was tightened up correctly. I realise that as it is a part sold by him that caused the problem he may not be your favourite supplier right now but i would still take it to him as he knows what he is doing.
 
gripper said:
The Hemmings valve has a mild steel seat and a stainless steel body. I have machining facilities albeit basic. Are there any details on

It involves machining the timing cover to accept a spring and ball and a different type pump to case seal.

The guy who owns AMR will send you the seal, spring and ball for a very nominal fee. I would ask him for machining instructions.

You need to do the pump mod, if you want to stop the wet-sumping from the pump internals, also.
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mikegray660 said:
I've posted how i have had 2 separate failure of the values, as other have too - yet they still get used and even championed by some folks on here. Hopefully your damage isn't to severe - but regardless it means a tear down and inspection - best of luck on it.
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+1
I would not use one.
If you must, then use an oil pressure gauge.
The Law of Murphy came a calling. Best of luck with your rebuild.
Tom
CNN
 
Oil pressure gauge.
Oil pressure gauge.
Oil pressure gauge.
Even if you don't have an anti wet sump valve, why not fit an oil pressure gauge, it can save a lot of grief and gives you an indication of engine condition?
If you don't want a pressure gauge, fit an idiot light.
 
Hm comnoz No inspired an idea with his slowly turned pre start wet sump device allowing pushing oil back to tank from pistons decent only, if some air pressure was let into the cases for a period ya'd know enough was oil back in tank to supply pump to start on, hm, if longer air pressure applied it may work as a pre-oiler too, hm.

Anti wet sump valve sieze (2015)
 
Hi hobot.
Do you reckon - 'Close the oiltank to aircleaner hose so the oiltank is pressurised by the crankcase breather at startup?'
Assumption: standard breather circuit with reedvalve cut into it.
 
mkv750 said:
I hope the damage is not too severe Gripper, and not too expensive to put right!.

I was going to fit an anti drain valve, in-line type, to my Interstate, but after reading on this forum,on the damage they can do when they stick, I decided to not go anywhere near it!, have just ordered one of CNW/Jim Comstocks breathers, 0500-09, lucky for me I can just bolt it straight onto the back of my crankcase, or rather my Norton's crankcase...

Lets hope the damage is as minimal as it can be,

John
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A breather won't have any effect on wet sumping John, I guess you know that though.
 
daveparry said:
mkv750 said:
I hope the damage is not too severe Gripper, and not too expensive to put right!.

I was going to fit an anti drain valve, in-line type, to my Interstate, but after reading on this forum,on the damage they can do when they stick, I decided to not go anywhere near it!, have just ordered one of CNW/Jim Comstocks breathers, 0500-09, lucky for me I can just bolt it straight onto the back of my crankcase, or rather my Norton's crankcase...

Lets hope the damage is as minimal as it can be,

John
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A breather won't have any effect on wet sumping John, I guess you know that though.
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You're right Dave, in that the Comnoz style breather doesn't prevent wet sumping... But it does go a very long way to preventing it from actually being a problem, as the breather 'pumps' the excess oil from the sump back to the tank very rapidly.

Provided the tank hasn't actually emptied itself into the sump (thereby starving the pump of oil when started) starting a wet sumped engine fitted with the Comnoz breather seems to have no adverse effects. Indeed, all that excess oil being flung over the cam and followers has a plus side!

So, the Comnoz breather allows you to live with wet sumping, without having to drain the sump each start up and without having to install any of the various devices twixt tank and pump.

(Just for info: I have the Comnoz breather that screws into the sump of my mk2a, I checked my own bike and it takes approx 7 weeks for the tank to empty to the point whereby the oil tank gauze filter is visible. I have started it after being stood for up to 5 weeks before without issue, as the breather returns the sump oil as mentioned above. But after seeing the gauze show itself at 7 weeks standing, I set myself a rule that if stood for more than 6 weeks I will drain the sump. But as this will only ever happen during winter, its a non issue anyway).
 
These stupid anti sumping valves were originally fitted to Velocettes. As we all know, these have roller bearing big ends which can stand a lack of oil for a lot longer than any plain bearing big end. Whilst many have no problems with them it really is like playing Russian roulette with your very expensive engine. I believe that Norvil in Staffs do the timing cover & oil pump mods. Tel: 01543 278008.
 
Hello Gripper, yes of course, you're valve did not stick!, I ought to have worded my post to reflect that.

Dave, you are right, and I do know the Comstock/CNW breather will not stop wet sumping, but as fast eddie has said, it will let me live with it, by pumping the oil back to the tank very quickly.

I am unsure though eddie, even if the tank has drained completely, filling up the sump, and the gauze in the oil tank is visible, as it was in Jim's wet sump start video, would not slowly turning the engine over, as Jim did, I think it was three turns on the kickstart, and the tank gauze was covered, would that not negate the need to drain the crankcase and refill the oil tank by hand?.

So, as long as the tank gauze is covered, I take it the oil will go to the pump, without the possibility of an air lock forming?, just as if one had drained the sump of excess oil and poured it back into the tank anyway?.

If one were to simply start the engine, straight off, with the oil tank gauze exposed, would there then be a chance for oil pump starvation, and subsequent damage?, or would the above breather simply pump the oil back quick enough to keep up with the oil pump on the initial start?.

Sorry if I am going off topic here, just seems to me the above breather is the perfect solution to the dreaded wet sumping issue.

John
 
mkv750 said:
Hello Gripper, yes of course, you're valve did not stick!, I ought to have worded my post to reflect that.

Dave, you are right, and I do know the Comstock/CNW breather will not stop wet sumping, but as fast eddie has said, it will let me live with it, by pumping the oil back to the tank very quickly.

I am unsure though eddie, even if the tank has drained completely, filling up the sump, and the gauze in the oil tank is visible, as it was in Jim's wet sump start video, would not slowly turning the engine over, as Jim did, I think it was three turns on the kickstart, and the tank gauze was covered, would that not negate the need to drain the crankcase and refill the oil tank by hand?.

So, as long as the tank gauze is covered, I take it the oil will go to the pump, without the possibility of an air lock forming?, just as if one had drained the sump of excess oil and poured it back into the tank anyway?.

If one were to simply start the engine, straight off, with the oil tank gauze exposed, would there then be a chance for oil pump starvation, and subsequent damage?, or would the above breather simply pump the oil back quick enough to keep up with the oil pump on the initial start?.

Sorry if I am going off topic here, just seems to me the above breather is the perfect solution to the dreaded wet sumping issue.

John
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Hi John,
I couldn't get my breather to return oil to the tank via kicking it over, well, not as fast as you describe. So, my fear was that if I started it up when the gauze was visible, would the pump empty the tank before he breather 'caught up with it' thus allowing air into the system?
I don't know the answer. But it just seemed a higher risk than I'm prepared to take! I have a new, standard, AN pump, and it takes a period of 7 weeks standing to expose the gauze, so for me, its a none issue as it'll only stand for that long over winter (normally) which is when I change the oil etc anyway.
 
Do you reckon - 'Close the oiltank to aircleaner hose so the oiltank is pressurised by the crankcase breather at startup?'
Assumption: standard breather circuit with reedvalve cut into it.
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My teachers/professors and guru/swamis say only asses operate on assumptions. There are a lot of assumptions with wet sump phenomina.
1st assumption [I don't have] is that there is much if any down side to full wet sump other than if so cold its difficult to kick over or reveals a bad crank seal.
2nd assumption [I don't have] is that its wear damaging to start if no oil in tank so takes a few seconds longer oil pressure to rise.
3rd assumption [I don't have] is the ZADP nano layer won't protect friction surfaces durring the few seconds before oil pressure hits.
4th assumption [I don't have] is oil tank needs to be pressurized for sump oil to return fast and easy to supply pump in enough time.
5th assumption [I don't have] is best if slow running to warm engine and flush sump oil before reving right up to cam break in rpms.
6th assumption [I don't have] is a hand full of less PSI from a restrictive AWSD or loose worn oil pump matters a whitworth d/t crank sling big end pressure.
7th assumption [I don't have] is oil guage has any use but decortivie except as protection/alert that an AWSD has failed again before riding off.
8th assumption [I don't have] is its more important to get big ends pressurized instead of cam/lifters splashed immediately - as oil or no oil in tank it still takes same number of revolutions to get head oil flowing enough to then drain onto cam/lifters.
9th assumption [I don't hold] is better to spend and modify for peace of mind on false assumptions than actual known oiling functions.
10th assumption [I don't make] is there's more reports warning us about the downsides going w/o AWSD than there is with some AWSD or unneeded replumbing.
11th assumption [I will catch flack for] is comnoz flapper valves being an improvement rather than just proven not to casue oil stravation which stock systems don't either.
12th assumption [I do know] is the potential freed hp of comnoz flappers to lower case pressure for better ring seal and less windage but has nothing to do with wet sump issues [unless a factory Combat] so very few will realize a power benefit if not operating into red danger zones.
Anti wet sump valve sieze (2015)
 
I must be missing something here!
How can a breather "pump" oil back to the tank? The breather is only dealing with crankcase pressure so I cannot see how it can positively return oil to the tank. Wet sumping and crankcase pressure are two entirely different issues.
 
Thanks eddie, fair comment there, best to be safe, for sure.

Yes, seven weeks is no issue, in the riding season, and as you say, start the new season with fresh oil.

John
 
daveparry said:
I must be missing something here!
How can a breather "pump" oil back to the tank? The breather is only dealing with crankcase pressure so I cannot see how it can positively return oil to the tank. Wet sumping and crankcase pressure are two entirely different issues.
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Dave, if you do a search, Comnoz posted a video showing how it works. The Comnoz reed valve I have screws into the bottom of the sump. The other type bolts to the back of the case. Both types allow a set amount of oil t stay in the sump. But excess oil will be 'pumped' back to the tank thus:
The breather is not timed. The reeds mean that pressure only goes one way. So, if thereis excess oil in the sump, it will cover the breather outlet and the descending pistons (that create the crankcase pressure) will push the oil out of the breather and past the reed valve. The reed valve will not let the oil return when the pistons ascend. When the pistons descend again, more oil is pushed out. This continues until all excess oil has been pumped out and back into the tank (this is of course, assuming that the breather hose is actually connected to the oil tank). So, effectively, the pistons actually 'pump' the excess oil back to the tank via the reed valve breather.
This dos not happen with the stock set up.
Hope this makes sense?
 
Number of reports of problems related to manual antisump valves with ignition or other interlock- zero

Number of dire warnings about such valves by those who have no experience in using one- 7,293


Glen
 
worntorn said:
Number of reports of problems related to manual antisump valves with ignition or other interlock- zero

Number of dire warnings about such valves by those who have no experience in using one- 7,293


Glen
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No dire warnings from me Glen... But I am not keen on adding something that I don't need. And with the breather set up and oil pump on mine, I don't need owt else.

I actually think that yours, with the built in ignition key holder thingy, is the best one of the lot. If I needed one, I'd copy that. But then I'd have to fit an key operated ignition switch as well!

I like to keep my bikes as simple as possible... To match my intellect...!
 
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