Unraveling the 961 part two (oil in the air box)

Hi Just my little input. I had almost forgotten but I had a similar problem on my 2015 Dommie. Not nearly as bad a yours but a definite concern. After about 6 weeks at the factory I was told that when manufacturing the frame it had been done incorrectly and internal size was allowing me to put too much oil in the system. Therefore using the stick to measure was showing an incorrect reading. After this the system was drained and I started measuring the amount which resolved my issues. It seems like you are going down the same path Good Luck
 
Bluey72e said:
Hi;

Ok so added 250ml as there was literally nothing on the stick and wasn't comfortable riding like that.

Went for 45 mins run and 10 mins was a constant 4krpm on highway.

literally 2ml on bottom of stick now but no oil in airbox at all.

Cant really judge if that seeping down if there's nothing on the stick to start with to measure from.

All I can say is that there is approx 2 litres in there as there was a measured 2.5L to start with.

Ollie has instructed me to drain everything, fill with 1.8L and then add up to 2.2(max)


From your results Id say yours is nye on perfect or at least normal for a 961
Click to expand...

Bluey ,

Step 1 : You must stop the wet sumping . Or drain the sump before fore each ride ?

Step 2 : Keep oil level half way up the knurl on the "new longer , lower marked ,dip stick" . Bear in mind that everyday your bike is wet sumping when parked . I think that 2.2 L is maximum , it might be less to get half way up the dip stick knurl say 2 L . Add slowly and check often !

As was said earlier , I think your oil pump may be leaking tank oil into the sump when parked. If the oil level on the dip stick goes down (drops) when parked , you are wet sumping !
 
Bluey72e said:
Hi;

Ok so added 250ml as there was literally nothing on the stick and wasn't comfortable riding like that.

Went for 45 mins run and 10 mins was a constant 4krpm on highway.

literally 2ml on bottom of stick now but no oil in airbox at all.

Cant really judge if that seeping down if there's nothing on the stick to start with to measure from.

All I can say is that there is approx 2 litres in there as there was a measured 2.5L to start with.

Ollie has instructed me to drain everything, fill with 1.8L and then add up to 2.2(max)


From your results Id say yours is nye on perfect or at least normal for a 961
Click to expand...


Cant really judge if that seeping down if there's nothing on the stick to start with to measure from.

You are wet sumping BAD bro ! You gotta fix this first . This may be your only real problem !
 
Luckily mine dosent blow any, I removed all the Evap system and upped the bottle to a real can......Trooper! ran the crank breather direct to the full pint
can along with gearbox breather and fuel overflow. its all sorted and nay worries if decides to puke randomly one day. easy fix, Still wish I could upload a photo, might crumble and spring for the VIP soon....cheers Adrian
 
Ok same oil level 5 days later.

I don't think its wet sumping in the usual meaning, I think that the scavenge pump is weak or an engine speed related issue and after a good ride the sump accumulates excess oil.

The Oil is low now but was low after my ride, then I dropped all the oil out the sump, it has not lowered since though. On many occasions I have left for a ride with oil on the stick and then upon checking when home its considerably lower. I always warm the engine for 2 mins and leave for 1min (as per manual for checking oil level) and found the oil back up to level so assumed at tick over it sufficiently pumps the oil back up. The level in below image is a few mm higher after my last warm up and oil level test (post dropping oil out sump to measure crank oil) that is in keeping with the usual, ride, oil low, warm up oil higher.

I think I had less stress getting divorced than this bike, considering its only done 1500Klms and essentialy brand new.

Anyway, I have sent an email to parts@norton to get a quote on a new MKII Oil pump or at least the oil pump check.

Going to raise the level to the bottom of the Knurl and re test everything after a ride.
Unraveling the 961 part two (oil in the air box)
 
Have you checked you oil return line check valve ? The one between the oil pump and the oil cooler. It should allow flow towards the cooler but not not back to the oil pump. You should remove it and make sure it is free flowing , same for the oil cooler. Also you can replace it if you haven't yet. You can test oil pressure by putting a gauge in the oil drilling hole at the base of the cylinder , there is a specification in the Euro 4 manual (1.5 Bar =21.7 PSI @1000 rpm with 10w40 oil) . Look at the page where it describes the cleaning and checking of the relief valve.
 
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Topped her up (100ml) to bottom line, went for 40 min ride max 6k rpm 10 mins down highway at 4k rpm.

Nada on stick.

I'm convinced now, the oil pump scavenging is useless no ? I don't think its wet-sumping standing and seeping just not returning it to the tank.

Will run for 2 mins in morning, 1 min wait and see what we get, my prediction is back to bottom line.

1591084717742.png
 
TonyA said:
Have you checked you oil return line check valve ? The one between the oil pump and the oil cooler. It should allow flow towards the cooler but not not back to the oil pump. You should remove it and make sure it is free flowing. Also you can replace it if you haven't yet. You can test oil pressure by putting a gauge in the oil drilling hole at the base of the cylinder , there is a specification in the Euro 4 (1.5 Bar =21.7 PSI @1000 rpm with 10w40 oil) .
Click to expand...

Yes checked that valve, removed the black plastic it was shrouded in and opened it up, the flapper valve (not ball type) was ok and I could freely activate it, also when changing oil I removed banjo bolt and other than the initial drip or so did not empty the oil cooler.
 
Next you can pull off the pump , check all the O-rings especially the return side they need a good seal . If there is a leak then maybe no scavenging ? While there make sure your passage to the sump return side is clear , from oil pump hole on crank case to bottom of sump (gently blow air) . You can do a simple test with the oil pump spin the shaft and make sure its drawing in return side oil . Disassemble and check relief valve and rotors inside if need be. Make sure its not stuck etc..
 
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Make sure you are at a correct starting point with your oil level . Start with empty oil tank , empty sump and put in correct known amount say 2 L and test again (check stick , start engine idle 2 minutes shut off check stick again. This is your starting point. When I checked my sump oil level last time , I removed 450ml so I put 450 ml back in the tank . Before I started the engine the oil level was high on the stick (of course) . After starting and idling a minute or two , the oil level on the stick was right where I started.before draining sump . This is what you should have.
 
Well Well Well.... Looks like things have really taken a turn for the best at Norton.

Look here what arrived this morning in my email.


Good morning;

Your details have been passed onto me by the parts department.
Would you mind sending me some information about the bike for some records?
Would like to have the VIN, model year and mileage.
When was the kit installed? noticed the oil after the installation of the kit?

--
Kind Regards
Maximiliano Muller
Technical Advisor/Senior Engine Builder
 
TonyA said:
Great News , Max Muller is back at Norton . Good Luck Bluey !
Click to expand...

Whats to note here is that my email was to parts, they actually read the email and rather than just quote me replacement parts they "Want to Help" fix it.

Very happy with just that concept :)
 
Update;

Since dropping the oil from the sump (670ml) and slowing adding back small amounts and watching the level's I have NOT had any excess oil in the air box, in fact to date its actually acting like I always hoped it should i.e a few drops after a couple of hours run is all !!!

Have been talking to Max Muller at Norton, he thinks as the engine is only just run it that in fact the rings need seating properly.
Hope Max doesn't mind but some of his responses as below that made sense to me.

"So after you drained the original 670ml (it varies between engines but 670ml seems a bit much), oil in the airbox has decreased? YES
1 or 2ml seems ok.
Fingers crossed but would you mind testing it a bit farther by riding the bike? Maybe there was a bit of debris in the oil pump check valve and/or external check valve and now it has cleared?
The amount of oil seems to be correct. around 2.5 liters.

One thing to note also is that the piston rings are also breaking in , it is advised to load the engine in order to seat the compression rings and to engine brake in order to seat the oil rings in the pistons.
I have seen instances of positive pressure build up in the bottom end thus oil in the airbox issue while piston rings are seating. Does that make sense? "


Week end before last did some steep steep hill work so did both the engine loading and engine braking to the extreme. !! maybe that's fixed me up.

Thanks to TonyA for all his help and Max Muller the man himself !!
 

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