leaking crank seal

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hi guys
it's easy enough to explain how i fitted the valve
the fat tube coming at a right angle from the valve was connected to the casing breather outlet
the tube from the end of the valve goes to the oil tank
for starters it would be pretty hard to fit it the wrong way and secondly it is a one way valve, from the casing to the tank.
the engine did run no doubt, but upon a burst of the throttle as when say over taking, she struggled a bit as if she was being starved of juice , air or both until there was a burst of power and revs were increased. i run a mikuni carb 3250 miles old, nothing but joy there.
i'm no expert. enthusiastic amateur perhaps and i'll have a go. but there is only one way the valve can be fitted. you can only blow through it one way.
from casing to oil tank as photos from previous posters have shown. jimc, sorry mate but i'm only telling it how it is. i can only assume that the breather was restricted by the valve. perhaps the breather pressure is not strong enough to push the valve fully open?
upon removing the pcv and putting the reducer back on she ran fine, and it appears as if there was very little difference in the leaking crank seal.
the new seal mentioned by seeley920 will be fitted tomorrow.
the stator studs are fine, and though i understand this could be an issue in this case it is obvious where the leak is coming from
the primary cover is cut and shaped so that the clutch and belt are exposed and all the workings are visible
cash, although she leaks a lot more when hot, there was a very slow leak from the crank seal if left sitting. this is what i mean by not in use. mind you she was left sitting from november 3rd following a pretty serious accident on my honda. the pan i had underneath the commando collected about a third to half a cup of engine oil over this time
simply said the pcv xs 650 part did NOT stop the leak from the new norton crank seal supplied by norvil. worth a try though.
the bike is 36 years old now and has covered unknown miles. it is within the realms of possibility that there has been wear around the casing or the crank.

cheers
chris
 
I would think if you can see the seal leaking then it would leak with or without the reed valve, The reed valve is going to help with weeping of oil not leaking. The valve won't cause what you are describing as far as I have ever heard of, Are you sure it's functioning properly? Both my bikes have them and run strong and I have had them on for awhile now. I hope the new seal works for you and that cures you problem. Chuck.
 
hi chuck
the leak is a slow drip only when hot (approx 2-3 drops/minute)
the valve does require a little effort to blow through though, more so with a 350mm length of oil line attached. there are no kinks in the line.
i can only speak from the experience i have had with this issue
regards
chris
 
I think your on the right track, Get the leak fixed and maybe go back and try finding out whats going on with the valve later. A good oil tight Norton should not need one to begin with, But once they have miles on them the valve does help with those nagging little weeps that show up. Let us know how things go, Chuck.
 
cheers chuck
agree with you there mate and when i resolve this drip issue i may not need the valve
sure is a hot topic though, seems like its a fairly common problem this crank seal.
don't want to shitcan anyone here but i'm not comfortable with using resin or loctite to stop leaks (if i can help it)
my bike seems to run better without the valve. does 75mph at 4000 revs with a mikuni carb and a 23 tooth drive sprocket sound reasonable?
sure feels and sounds good and as this is my only commando i've nothing to compare it to.
cheers
chris
 
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