1975 Mark III Oil Separator and tubes

thackero · Mar 2, 2015

Does anyone have any pictures of where the oil seperator and it hoses are located. Most people must of junked this item however I have one in my box of parts and would like to refit it if I can find out where it is mounted. Thanks

comnoz · Mar 2, 2015

thackero said:
Does anyone have any pictures of where the oil seperator and it hoses are located. Most people must of junked this item however I have one in my box of parts and would like to refit it if I can find out where it is mounted. Thanks

I don't know of an "oil separator " on a Mk3. Maybe post a picture and we can identify it. Jim

Hortons Norton · Mar 2, 2015

Maybe he's talking about the chain oiler?

Anonymous · Mar 2, 2015

Perhaps the components you mention are in the picture at this website.

https://www.oldbritts.com/oillines.html

Stephen Hill · Mar 3, 2015

Oil tank breather, as per Old Britts diagram?

Stephen Hill

L.A.B. · Mar 3, 2015

I don't have the oil separator, but the photo below shows where the separator breather tube 065497 connects to the Mk.III airbox.

http://www.nortonmotors.de/ANIL/Norton% ... 20&Part=34

Hortons Norton said:
Maybe he's talking about the chain oiler?

Mk.III's didn't have the chain oiler.

PeterJoe · Mar 3, 2015

I don't have a picture of the oil separator mounted however, the Norton Mark III Rider's Manual has an illustration on page 10 (pdf page 9) that shows the oil separator. It mounts directly to the breather hole on the left hand side of the airbox.

http://britmoto.com/manuals/Manuals/Riders_4.pdf

Deets55 · Mar 3, 2015

thackero,
Here is a parts break down from Old Britt:

http://www.oldbritts.com/1975_g20.html

What I don't like about this system is the bottom of the oil separator (part #34) has a line that tee's into the carb balance tube. I makes getting a good consistent idle hard to achieve (for me anyway). Once I removed the line is was easy to get the bike to idle good. I just ran the hose from the oil tank breather into the air box. The problem with that is I get oil vapor in the air box and it will eventually come out the bottom. It's not much but now I am thinking about re- installing the separator and blocking off the small line and just using the separator as a vapor trap.
Pete

comnoz · Mar 3, 2015

Deets55 said:
thackero,
Here is a parts break down from Old Britt:

http://www.oldbritts.com/1975_g20.html

What I don't like about this system is the bottom of the oil separator (part #34) has a line that tee's into the carb balance tube. I makes getting a good consistent idle hard to achieve (for me anyway). Once I removed the line is was easy to get the bike to idle good. I just ran the hose from the oil tank breather into the air box. The problem with that is I get oil vapor in the air box and it will eventually come out the bottom. It's not much but now I am thinking about re- installing the separator and blocking off the small line and just using the separator as a vapor trap.
Pete

That must be why I have never seen one. They had all been removed from the three MK3's I own before I got them. Jim

Deets55 · Mar 3, 2015

Jim,

I think the system would have worked if they had placed that tube from the separator before the carbs, instead of between the carbs and head.
Pete

1975 Mark III Oil Separator and tubes

thackero

comnoz

Hortons Norton

Anonymous

Guest

Stephen Hill

L.A.B.

Moderator

PeterJoe

Deets55

comnoz

Deets55

Similar threads