Oil leaks on 961 MKII

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Jan 18, 2017
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Anyone else having oil leak issues with their MKII?

Thought the oil leak issues were supposed to be resolved on the 961 MKII bikes, but mine is pooling oil on the cooling fins at the front of the motor and oil is also pooling at the back of the motor on the base. Assuming this is working its way down from the valve cover. This started on the very first ride, only put 50 miles on the bike.

Dropped it off at the dealer today for warranty repair.
 
Thats a new one for me. Ive never heard of oil leaking out the cover or upper engine. Could be a simple hose loose from the oil tank. These bikes are hand assembled. Keep us up to date with this please.
 
RKF848 said:
Anyone else having oil leak issues with their MKII?

Thought the oil leak issues were supposed to be resolved on the 961 MKII bikes, but mine is pooling oil on the cooling fins at the front of the motor and oil is also pooling at the back of the motor on the base. Assuming this is working its way down from the valve cover. This started on the very first ride, only put 50 miles on the bike.

Dropped it off at the dealer today for warranty repair.

Hello , Are you saying that it appears that it is coming from the rocker cover gasket seam , from the head gasket seam or the base gasket seam ? Do you also have oil pooling under the starter ? Give the engine a good washing and carefully take some pictures close up after your short ride. Send those here and let us have a look please. How many miles on the bike and is it due for a head torque check ? Also , If you don't have the trans vent install asap..
 
I believe it is coming from the rocker gasket seam and working it's way down. Most of the oil is pooling underneath the exhaust headers outlets. There is also some oil underneath the starter. I'm unable to post pictures at this time.

Picked up the bike with 2 miles on the clock, it now has 50 miles. It's at the dealer now.

Dealer had a 961 and 961 MKII in inventory, so I decided on the MKII with a build date of Oct. 2016, figuring most of the earlier issues would have been sorted out. Funny thing was, both bikes had a drop of oil underneath the starter motors and these were brand new bikes. I showed this to the dealer and they did not have an answer as to where the oil came from. Dealer is new to Norton and I'm their first customer, so they don't really have any history with 961 issues.
 
Have a close look around banjo Bolt/breather area.

Don't touch or tighen them - as I'm sure Richard will say - but that's where my leak was.

Very very subtle but flows to gasket seam and makes it look like from gasket then goes into to the front of canted cylinders.

Also because oil is mist from there worked it's way back when I was riding.

Original cover also had misaligned oil baffle (siliconed) but doubt that would mean much in terms of leak
Dealer tighted banjo too much ....unbeknown to me during a service.

I changed rocker cover and bone dry since.
 
99% chance if oil around starter its the lack of transmission vent. Which is an easy fix but factory wont pay for it. So save yourself the trouble and just get one and install it yourself. As far as rocker cover. It you still had in your possession then check how tight the bolts are. But be warned. Tighten evenly or you could warp the cover.
 
I had an oil leak pooling underneath the starter. They determined it was the starter gasket, (not) the crankcase seam (doubt it) and it WAS actually the started itself. Once the changed the defective starter, never leaked again. They had gotten a bad batch of starters with bad O rings inside. It only took two years and practically a total rebuild. :? Good luck. Mines a 2013. You may fare better with the MKII
 
Here is the issue;
There is no vent for the trans. So pressure builds. I know about the starter seals and what not, and agreed 9/10 times thats the spot the pressure pushes oil out of, but a better seal just holds it better or forces the oil to find the weakest spot. A vent (make your own if one feels inclined) completely solves this issue. Better seals is just a band-aid.
 
My dad was determined to find the best seal and did. Because of the same issue. Then discovering that oil started coming out other spots when he fixed it with viton. Looked to see if the vent was clogged and at that moment discovered there was no vent. Couldn't believe it when he went to Oregon a year later and seen Kennys design had a vent. So that proved he did the right thing. Thats when we started making them for the public.
 
I am willing to bet the leak is assembly error at the factory. Either a loose hose clamp or the valve cover needs a tighten. Although its upsetting, don't loose sleep over it. The bikes are amazing. But they are hand built so these things happen. Once dialed in, you will have no regrets of purchase.
 
Richard. No doubt the vent is a vital piece and should be installed, but even after I installed that AND Norton upgraded all the venting systems on the bike that they put on the newer models, the starter still leaked. It never really worked correctly anyway. Always a loud "whack" when starting. As soon as that was replaced, the bike started beautifully and the oil leaks stopped. I'm not saying this is the original posters problem, just my experience. By all means...I bought the vent and so should any other 961 owner.
 
OK, so I think I’m paying the price for ignoring wiser heads on this site! I have an oil leak on top of the engine, below the starter motor. No, no........ I did’nt fit the gearbox breather! I tried to get this fitted under warranty when the bike went in a few months ago for the oil in airbox mod. Thought I was going to get the breather at the same time. Did’nt happen.

The leak arrived after the airbox fix so I suspect the in-line filter first as has been reported on the site and starter motor seals is another possibility. Now wishing that I’d just ordered the breather months ago so I could have taken that out of the equation. Going back to the dealer next week so I will let you know the outcome. Have to admit that I am reluctant to work on the bike myself while it is still under warrant and the dealer is less tha 100km away!

Steve
Sunshine Coast
 
Richard. No doubt the vent is a vital piece and should be installed, but even after I installed that AND Norton upgraded all the venting systems on the bike that they put on the newer models, the starter still leaked. It never really worked correctly anyway. Always a loud "whack" when starting. As soon as that was replaced, the bike started beautifully and the oil leaks stopped. I'm not saying this is the original posters problem, just my experience. By all means...I bought the vent and so should any other 961 owner.

A VERY LARGE amount of starters on factory Nortons do not have the needed seal in the starter. The vent prevents pressure pushing out the seal. With no seal at all, splash will leak out the starter.
 
Hello again Richard-7 ! Yes Steve get the vent fitted asap , this may stop the leak you have started. I can vouch for the goodness of the New Starters coming from Norton now . They are sealed , oil leak free and smooth running !
 
Tony,
So what this means is that there was an standard "undocumented" 961 trans vent.
It was supplied though the original starters.
Those Norton guys, they thought of everything.;)
 
Just about to purchase the vent kit, it is A$200 with the exchange rate and postage to Aus. Has anyone ever had one of these fitted under warranty? It would appear to be a necessity in order to prevent oil leaks and potentially expense in other areas; changing starter motor seals etc. This is evidenced by the fact that Norton have included it to the MKII as standard fitment.
 
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Just about to purchase the vent kit, it is A$300 with the exchange rate and postage to Aus. Has anyone ever had one of these fitted under warranty? It would appear to be a necessity in order to prevent oil leaks and potentially expense in other areas; changing starter motor seals etc. This is evidenced by the fact that Norton have included it to the MKII as standard fitment.
NOOO don't do it .
$10 worth of parts from your local hydraulic shop !!!!
 
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