NEWSFLASH - 961 OIL IN AIRBOX FIX

Fast Eddie

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The trans vent helps stop trans leaks and has no bearing on the oil in the airbox issue.
Actually, I thought that mk11 machines already had a trans vent from the factory (unless it’s just later ones)?
The oil gets into the airbox via the engine breathing system. The factory have had a number of different iterations of ‘fixes’ for this.
All I can tell you is that the latest ‘fix’works, at least it does on my bike.
Without knowing exactly which ‘fix’ your bike has already it will be difficult to suggest what you need to do.
So unless you’re quite knowledgable on Norton fixes in general I suggest this would be a difficult and perhaps rather frustrating thing to attempt a DIY fix for.
Far better if you have a trusted dealer or mechanic that could do it.
 
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I've installed the 0ne-07 trans vent on my 2016 Sport MKII but I still get oil dripping from the airbox. I just keep a screw in the drain tubing and unscrew it every once in a while to let it drain. But this cannot be normal. I have never had a vehicle lose this much oil on a regular basis. Is the kit mentioned above the next step to take? What exactly does this kit do? And is it a simple install like the vent kit or something I have to find a dealer to do? Thanks

Not all Mk2 had the trans vent . It wasn't until recently that Norton were installing them . Asad , if your bike is a 2016 Mk2 , then you already have the air/oil separator and the non-return valve in the oil return line between the oil pump and oil cooler ? I have just looked at pictures of your bike and you have the separator. I don't see the non-return valve in the oil return line . perhaps you have the latest style oil return pipe in your frame like the 2018's ? Email Norton to find out.
How much oil are you getting in miles per ml ? Measure the oil that comes out and track the miles. Do you have the latest oil dip stick with the new lower markings ? Do you have the little plastic catch bottle on the frame ?
 
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BritTwit

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Asad,

Are you sure that you are not overfilling the oil?
How do you check the oil level in your tank?
Do you have the new style, longer dipstick with the knurled bottom section?

If you have the fix installed and are still getting oil in the airbox then it may be an overfill issue.

The MK II commando should have the oil-in-airbox fix installed.
Does your bike have the inline, one way valve in the return line from the oil cooler?
This helps to limit the amount of oil that accumulates in the engine sump.

Do you have the oil/air separator behind the cylinders?
This helps prevent the oil that does get through the breather from getting to the airbox.
 
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Hello Brit Twit yes he does look at his pictures in Domi flyscreen on a commando. Also the new dipstick came out later. Richard Pearce MK2 had to go back to the factory for it.
 
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1. How do I check if my bike has air/oil separator and non-return valve?
2. I already drain the oil from the airbox at the end of the day and keep the tubing plugged with a screw while riding so maybe I do not need to do anything else with the airbox oil issue.
3. The issue that is bothering me currently is that I can see small amounts of oil sprayed on to the frame and some browning (?oil) of the air cooling fins (see pictures below). I cannot figure out where this oil is coming from. My bike just hit 520miles today and I know that I am supposed to do a head torque at a 1000miles to avoid a blown head gasket. Is it possible I need to address this early? Or is this oil a sign of different problem? Thanks for your help.



 

BLIGHTYBRIT/SF

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1. How do I check if my bike has air/oil separator and non-return valve?
2. I already drain the oil from the airbox at the end of the day and keep the tubing plugged with a screw while riding so maybe I do not need to do anything else with the airbox oil issue.
3. The issue that is bothering me currently is that I can see small amounts of oil sprayed on to the frame and some browning (?oil) of the air cooling fins (see pictures below). I cannot figure out where this oil is coming from. My bike just hit 520miles today and I know that I am supposed to do a head torque at a 1000miles to avoid a blown head gasket. Is it possible I need to address this early? Or is this oil a sign of different problem? Thanks for your help.

There is a drain hole on each cylinder head between the third set of cooling fins from the top , have u a loose plug ? Or is oil tracking down there somehow ? The transmission vent is to relief pressure when hot, & to prevent starter motor seal from leaking I believe ,my mk2 built late March 2016 ,didn’t have trans vent on , they only started that approx this time last year I believe , & had the check valve put on in May 2016 , my newer dip stick was put on on a service end of 2016

 
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Just checked and I do not have plugs in those holes. They are just open on both sides.
 
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I just checked oil level and it is mid way between the top and bottom marks on the dipstick.
 

BLIGHTYBRIT/SF

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I just checked oil level and it is mid way between the top and bottom marks on the dipstick.
Drain holes are just that , if the spark plug recess fills with water when parked ! , if spark plug is loose , oil / petrol would seep out via the drain holes, there open , not plugged off
 

BLIGHTYBRIT/SF

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I just checked oil level and it is mid way between the top and bottom marks on the dipstick.
I think if u have oringinal dip stick, just fill to bottom of stick only ,Tony A is good on this point , if u overfill then u will get more oil in airbox
 
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Fin staining is usually loose exhaust header nuts. Its a known common problem by Norton. One fix is double exhaust header crush gaskets.

For oil in airbox, we can rebuild your engine so that doesn’t happen anymore or you can use Nortons retro bandaid system. Either works. If you’re ambitious you could pull the head and see if the rings are lined up. I bet they are. One way to check is to pull hose from air box and put a balloon on it. If it in inflates while running, then they are aligned, or ring to bore to too large. Easy fast test—- If the balloon inflates and deflates with every stroke of piston then its not that. Try balloon and rev it up. Shouldn’t matter revs. Balloon should not blow up. I could make a video of this if needed.
 
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I think if u have oringinal dip stick, just fill to bottom of stick only ,Tony A is good on this point , if u overfill then u will get more oil in airbox


This might be the problem. I probably have the original dipstick. Anyone know how to tell for sure?
 

BritTwit

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The new dipstick has a knurled lower section
The original has no knurling just a high and low line.

The stain on your cyl head fins looks like it originated from the sparkplug drain hole.
Probably what was stated previously.
If it were a head gasket problem, the cylinder fins would be stained as well. Yours are clean.
Just be sure to have the head re-torqued before 1000 miles.
 
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Would it be possible to get oil pooling in this area of the engine as well from the cylinder drain holes? Second picture is a zoomed in view of the first picture.

A Closer look of the above picture.
 
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Good advice guys , Asad check your spark plugs are tight. Then check exhaust nuts are tight . I am running two exhaust gaskets per port works good. Install first , crush , install second crush, and then set to factory spec torque.
Check after 500 miles then retorque to spec.
 
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That's the starter leak . I see you have the trans vent OK . Put your fingers under the starter only , where it bolts to case. feel for oil . Hello Richard ,is it possible that a 2016 does not have the o-ring seal ? Above all , Don't worry and prioritize . I agree with number 2 above , leave airbox drain plugged and monitor . Also how much oil wet sumps back to the crankcase after you park and don't run the bike for a week ?
 
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So I have the OLD dipstick and it is currently filled to the midway between the two lines. I should keep it at the lower line?
 
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