New owner oil leak help

jeffmack · Feb 16, 2012

Hear ya on the crankshaft seal, would that have been replaced when the new inner primary was fitted?
Also, while I am out of town I wanted to pick up the proper oil line hose so I can install the xs650 early next week. Can someone post the proper hose for the mkiii? Size? Thanks, will update all the findings when I get home

DogT · Feb 16, 2012

JimC said:
I, too, had a non PCV valve Norton, a 1969, that was a non leaker after I rebuilt it. I suspect it was the rotary breather of the 1969 Commando that made it so. The 1972 Combat I have now leaked and weeped in more than one place until I got rid of the crankcase pressure.

I won't dispute that. I have a drip, but unknown from where, thinking it 's the crank flange after rebuild. However I doubt that the timed breather on the 69/70 is adequate to keep the pressure down in the crank except at low speeds. I was hoping that comnoz' breather would help, but unfortunately my early frame has the brace right below the sump and mine is so close I couldn't install it. Bummer. Only one he has had not work so far, just my luck.

Dave
69S

JimC · Feb 16, 2012

DogT said:
JimC said:

I, too, had a non PCV valve Norton, a 1969, that was a non leaker after I rebuilt it. I suspect it was the rotary breather of the 1969 Commando that made it so. The 1972 Combat I have now leaked and weeped in more than one place until I got rid of the crankcase pressure.

Click to expand...

I won't dispute that. I have a drip, but unknown from where, thinking it 's the crank flange after rebuild. However I doubt that the timed breather on the 69/70 is adequate to keep the pressure down in the crank except at low speeds. I was hoping that comnoz' breather would help, but unfortunately my early frame has the brace right below the sump and mine is so close I couldn't install it. Bummer. Only one he has had not work so far, just my luck.

Dave
69S

You are probably right about the timed breather being inadequate. It was a chain drive primary, so I would not have known if the primary was collecting engine oil.

donmeek · Feb 17, 2012

just my 2 cents. installed a motormite and it worked great. for about 500 miles. put in a Mikes unit and so far so good.What Jim says makes sense to me, so I put a mikes unit on the project bike as well, way before it's ready to run.Why wouldn't you install one when building a bike and everything is apart anyway?

cmessenk · Feb 17, 2012

Prior to Motormite...drips every day...lots of 'em. Motormite installed 9000 miles ago...I can thrash it on a 200+ mile Sunday....park it and not a drop. Evidence: Here's my trusty steed at a recent vintage Car & Bike show that was held a a local airpark. Organizers made all the Brit Bikes put a "bulls eye" oil catcher under our bikes to keep the tarmac from getting soiled. Every Triumph, Vincent, AJS, Velocette and BSA in our group had "shots" on their targets....Folks walking around looking at all the bikes came up to mine and exclaimed...."Hey, what gives?? There's no oil on the paper!!"

splatt · Feb 17, 2012

You don't have part of the chain oiler still hooked up do you ?

bill · Feb 17, 2012

Well Chip I guess that you TRAILERED it there with out oil in it :mrgreen: I would GUESS that it leaks less now than when you got it back from the PROFESSIONAL RESTORER :lol:

cmessenk said:
Here's my trusty steed at a recent vintage Car & Bike show that was held a a local airpark. Organizers made all the Brit Bikes put a "bulls eye" oil catcher under our bikes to keep the tarmac from getting soiled. Every Triumph, Vincent, AJS, Velocette and BSA in our group had "shots" on their targets....Folks walking around looking at all the bikes came up to mine and exclaimed...."Hey, what gives?? There's no oil on the paper!!"

Matt Spencer · Feb 17, 2012

He's changed the carb , so it doesnt leak Petrol either . :|

dougmatson · Feb 17, 2012

Check the grommet that seals the stator wire in the primary it's in the same area where your leak is. While running oil comes off the chain and into the scoop for the hydraulic chain adjusters and oil runs down the case that isn't collected , right around the wire and grommet that passes through the case. Mine was leaking there, only while it was running. The reed breather is a great idea and is my next improvement.

hershey · Feb 18, 2012

For what it,s worth, I installed the sx650 valve on my mk3. Remove the battery and mount it in the upper left hand corner above the battery as close to the frame and oil tank as possible without touching it . The oil line it sturdy enough to keep it in place without drilling holes. Hershey

Ondra_cz · Jul 1, 2012

Hi, Im a new owner of 72 Combat. Without any modification on engine unit, with oil drops from primary chain case. Crankcase getting pressurize and easiest way for oil is to primary (primary was overfilled after every ride 10km - 1dcl). Im afraid that only re-sealing will not help..

My question is - It will be helpful to keep original 72 breather case only as pipe and add XS650 reed valve behind it? Is it totally wrong idea or not?

Stillreel · Jul 11, 2012

I've opted for the XS650 valve but I'm hoping someone has a picture of the tube routing on a '71 (90 degree bend at breather port forward of alt housing). Should I fit it by the crack case, aft, somewhere in the middle, does it matter?

Thanks
BC

New owner oil leak help

Similar threads