Oil valve solution to oil falling to crankcase

I noticed the finish on the small plunger in cover , anti drain back valve , not that great , and read that they can stick , gave it light polish with 600 in the lathe , much smoother , also the support shaft that goes into the cover had .002" clearance but was causing issues it want to bite into the alloy , I had to diamond file and polish the champher , no problems after that slid on nice .
 

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Shelby-Right said:
I noticed the finish on the small plunger in cover , anti drain back valve , not that great , and read that they can stick , gave it light polish with 600 in the lathe , much smoother , also the support shaft that goes into the cover had .002" clearance but was causing issues it want to bite into the alloy , I had to diamond file and polish the champher , no problems after that slid on nice .
Click to expand...
I had to do the same with mine
 
Shelby-Right said:
I noticed the finish on the small plunger in cover , anti drain back valve , not that great , and read that they can stick , gave it light polish with 600 in the lathe , much smoother , also the support shaft that goes into the cover had .002" clearance but was causing issues it want to bite into the alloy , I had to diamond file and polish the champher , no problems after that slid on nice .
Click to expand...
The slight chamfer on the bottom of the plunger should stop it binding with the drillings in the chamber ...i did say should ?....just been farting around with a MK3 cover and plunger ...a slight polish should help as I found
 
KiwiShane said:
The slight chamfer on the bottom of the plunger should stop it binding with the drillings in the chamber ...i did say should ?....just been farting around with a MK3 cover and plunger ...a slight polish should help as I found
Click to expand...
Did you get yours from Tim, I checked the price at andover and it was 20nzd different without freight i got the last one , I think the next ones will be dearer .
 
Shelby-Right said:
Did you get yours from Tim, I checked the price at andover and it was 20nzd different without freight i got the last one , I think the next ones will be dearer .
Click to expand...
Not directly...YOU!!...emptied my shopping kart (last one)...🤣..so I got my cover elsewhere
Look how much classic spares are selling them for in aussie ?...over the top !!...we need to support our local dealers like Tim (good bugger)...which i do...his mark up is pittance ..
New stock kit...will be just over $600 I suspect...my new pump from Tim (ex AN) is making slightly more pressure than the old one when hot...(the good thing about having a gauge imo)
 
Sorry about that , Jonny on the spot ! 😬 , good being able to check the timing chain , I haven't ever re timed a boyer , easy didn't even need instructions .
 
Shelby-Right said:
Sorry about that , Jonny on the spot ! 😬 , good being able to check the timing chain , I haven't ever re timed a boyer , easy didn't even need instructions .
Click to expand...
I'm glad it went to a good home...instructions.?..what are they...😁
Do you have the MKIV boyer ?
 
KiwiShane said:
Not directly...YOU!!...emptied my shopping kart (last one)...🤣..so I got my cover elsewhere
Look how much classic spares are selling them for in aussie ?...over the top !!...we need to support our local dealers like Tim (good bugger)...which i do...his mark up is pittance ..
New stock kit...will be just over $600 I suspect...my new pump from Tim (ex AN) is making slightly more pressure than the old one when hot...(the good thing about having a gauge imo)
Click to expand...
KiwiShane said:
I'm glad it went to a good home...instructions.?..what are they...😁
Do you have the 629469, member: 13145"]
I'm glad it went to a good home...instructions.?..what are they...😁
Do you have the MKIV boyer ?
Click to expand...
yes previous owner fitted it . Seems to work ok , previous owner had it set at factory 28 deg , but the header pipes were black and searing hot , it took the skin off my calf in an instant, must be too retarded at idle I reset to 31deg all good .
 
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Okay - left it for a couple of weeks to ensure the fix is good - and I am very happy. No oil is going to the sump.

My lessons from this exercise are (stating all for newcomers)
1. Oil tank level will drop after a ride as the air bubbles in the tank rise and "pop' - maybe up to a quarter of high-low.
2. Don't assume "sumping" is through the pump. It may be the pump gasket or pump end-plates or ?? Pull the sump plug just in case.
3. The best way to make an assessment is to remove the timing cover with the oil tank full. Clean everything and watch.
4. All 3 of the AMR mods are worthwhile - the ball/check valve to stop any oil exiting the pump, the pressure relief exit re-drilling to stop oil bypassing the pump and the o-rings on the "pressure" side of the pump to stop oil leaking into the low-pressure side and.. into the sump.
4. The AMR mod can be improved by grinding a Dremel stone (the ones you never use!) to the same radius as the AMR ball (6.35mm) and creating a seat in the pump outlet bush.

I suspect many bike's sumping problems may be down to point 2 above.
Cheers
Rob
 
All of this is so weird to me . I've had 4 Nortons in this short little life and none of them have ever sumped . Stone stock .
My present MK111 sat all winter 5 months last year and started up first jab at the magic button with full choke no throttle after checking oil level which was just under half-way , as I left her , before flying away to kill fish and other beach activities for months . I have other oil pumps just in case and new gaskets and seals but all has been good . Knock on wood 3 X .
 
Torontonian said:
All of this is so weird to me . I've had 4 Nortons in this short little life and none of them have ever sumped . Stone stock .
My present MK111 sat all winter 5 months last year and started up first jab at the magic button with full choke no throttle after checking oil level which was just under half-way , as I left her , before flying away to kill fish and other beach activities for months . I have other oil pumps just in case and new gaskets and seals but all has been good . Knock on wood 3 X .
Click to expand...
Well, the Mk3 already has 2 of the AMR mods - the check valve on the outlet of the pump and the revision back to Dominator pressure relief valve plumbing.
Ask a cross section of pre-MK3 owners
 
Torontonian said:
All of this is so weird to me . I've had 4 Nortons in this short little life and none of them have ever sumped . Stone stock .
My present MK111 sat all winter 5 months last year and started up first jab at the magic button with full choke no throttle after checking oil level which was just under half-way , as I left her , before flying away to kill fish and other beach activities for months . I have other oil pumps just in case and new gaskets and seals but all has been good . Knock on wood 3 X .
Click to expand...
Minus 15 , in the shed ? Oil like treakle, 🤣🤣🤣
 
Shelby-Right said:
Minus 15 , in the shed ? Oil like treakle, 🤣🤣🤣
Click to expand...
So have you noticed a significant difference since you fitted the new cover ?
Up and back from Auckland today ...
still had a full tank of oil when I left at sparrows fart this morning ...👍
...out in the boat tomorrow morning for some Tarakihi ..😋 another cold start...love it !!
 
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