Problem I Haven't Seen Before

Finally got the timing cover off - had to split the gasket with razor blades. Then more nonsense. Auto chain tensioner jammed holding chain super tight. Some sort of anti-sump - maybe AMR, but the parts all fell out so I don't even know if I found them all. Had to use the nuts with thin metal protectors to jack the barrels off - same sealer. Then noticed that the pistons were on the wrong sides and the valves have been lightly touching them - will have to inspect the head and valves carefully - probably would have been worse but the cylinder base nuts were only slightly more than finger tight, and the head was not fully torqued down. Also have to check the piston clearances - it's a fresh bore and if the bores were matched to the wrong pistons no telling what I've got. And, just for fun, one circlip on the right cylinder was in past the slot and the other not to the slot - any chance they would have migrated into place? No, more likely a seized engine! This is the 2nd bike in the group of three that I bought that the pistons were in the wrong sides - best check the 3rd one I guess!

Back to it - lots of gasket scraping to be done.
 
Finally got the timing cover off - had to split the gasket with razor blades. Then more nonsense. Auto chain tensioner jammed holding chain super tight. Some sort of anti-sump - maybe AMR, but the parts all fell out so I don't even know if I found them all. Had to use the nuts with thin metal protectors to jack the barrels off - same sealer. Then noticed that the pistons were on the wrong sides and the valves have been lightly touching them - will have to inspect the head and valves carefully - probably would have been worse but the cylinder base nuts were only slightly more than finger tight, and the head was not fully torqued down. Also have to check the piston clearances - it's a fresh bore and if the bores were matched to the wrong pistons no telling what I've got. And, just for fun, one circlip on the right cylinder was in past the slot and the other not to the slot - any chance they would have migrated into place? No, more likely a seized engine! This is the 2nd bike in the group of three that I bought that the pistons were in the wrong sides - best check the 3rd one I guess!

Back to it - lots of gasket scraping to be done.
Jesus Christ
Who the hell built this motor?
 
Jesus Christ
Who the hell built this motor?
Don't want to say who I was told - now believe that to be a lie. Camshaft nut - no effort to get off. Crank worm gear/nut, not effort to get off. Took over an hour to get the cases apart. Crank has been split - tabs not bent. Conrods nuts - blue locktite and maybe 10 ft. lb.

Care to guess which thing would have blown this engine first?

Thoughts on keeping the timed breather verses sending to cNw for a breather upgrade. I don't know how well the timed breathers on Norton worked. A Triumph service bulletin said to discard but theirs was a little more complicated system.
 
Finally got the timing cover off - had to split the gasket with razor blades. Then more nonsense. Auto chain tensioner jammed holding chain super tight. Some sort of anti-sump - maybe AMR, but the parts all fell out so I don't even know if I found them all. Had to use the nuts with thin metal protectors to jack the barrels off - same sealer. Then noticed that the pistons were on the wrong sides and the valves have been lightly touching them - will have to inspect the head and valves carefully - probably would have been worse but the cylinder base nuts were only slightly more than finger tight, and the head was not fully torqued down. Also have to check the piston clearances - it's a fresh bore and if the bores were matched to the wrong pistons no telling what I've got. And, just for fun, one circlip on the right cylinder was in past the slot and the other not to the slot - any chance they would have migrated into place? No, more likely a seized engine! This is the 2nd bike in the group of three that I bought that the pistons were in the wrong sides - best check the 3rd one I guess!

Back to it - lots of gasket scraping to be done.
I've seen some real shady tree shit job repairs in my day. Heinz-57 bike and parts. Everything from 75 frames matched with an atlas gearbox..., Anything to put the bike together and out the door to leave for someone else to deal with its problems. It is good you took it apart to get it right.
 
Please stainless lovers, use anti-seize!

Got all rigged to pull the engine. - ready to remove 4 bolts, jack it up, and it's out, NOT! The big bolt through the front iso was beautifully polished stainless installed without anti-seize. The nut unscrewed about two turns and stuck. I used bigger wrenches and got it a little farther until I pulled a muscle in my arm. The I tried my 600 ft. lb. capable impact - just rounded the head of the bolt. OK, angle grinder time. Hate using them inside the shop so put towels everywhere in the area to catch the mess and started at it. Very difficult place to do that without hurting anything else but I finally got the nut split down the middle and off. The other three stainless bolts were not seized - because they were barely more than finger tight!

At any rate, the plate on top of the cylinders has many purposes. It is just a 1/4" square of aluminum with holes drilled as needed and some tapped for various pulling, case splitting, lifting, etc. purposes.

Now I can take apart another engine, to get a crank. I have two "on the shelf" but the timing side of both is with Jim Comstock to have the seal surface de-gorrilla'ed. Of course, first I have to get the glued-on timing cover off. Hopefully easier out of the bike - tried a longtime in the bike - gave up.

View attachment 98631
Stainless is for salt water fishing boats.
 
Don't want to say who I was told - now believe that to be a lie. Camshaft nut - no effort to get off. Crank worm gear/nut, not effort to get off. Took over an hour to get the cases apart. Crank has been split - tabs not bent. Conrods nuts - blue locktite and maybe 10 ft. lb.

Care to guess which thing would have blown this engine first?

Thoughts on keeping the timed breather verses sending to cNw for a breather upgrade. I don't know how well the timed breathers on Norton worked. A Triumph service bulletin said to discard but theirs was a little more complicated system.
Reed valve breather is a must do IMHO. Either crank case or sump, but def one or t’other.
 
Stainless is for salt water fishing boats.
I don't mind some stainless on a bike, but there must be anti-seize! The only place I use it is for things like stainless fenders where standard fasteners look bad or things that are only available in stainless (one-piece rear axle).
 
Reed valve breather is a must do IMHO. Either crank case or sump, but def one or t’other.
I guess it has to be crankcase. Can't even get a socket on the big sump plug on this bike.

I do wonder how well times the Norton timed breather is. If correct, it should do the same job as the reed valve. I think Triumph eliminated them because that leaves the engine open to release the pressure of the piston going down. Of course, it doesn't create a vacuum because it's open with the pistons going up as well.
 
Personally, I don’t think so.
Let the reed valve work as intended IMHO.
Hmmm it's something I have wondered about
Before I had the internet I used to have to think for myself I didn't have you lot to rely on
I fitted a reed valve from an oxy acetylene gun to the timing cover blanking plate
I teed this into the camshaft breather pipe then back to the oil tank
Back then my commando was smoky and the bores were oval
I figured it needed some help with ring blowby
After a few years I finally got around to getting a rebore
Quite a few more years passed and the bike ran happily,no oil leaks or problems with the engine
Then I fitted an Alton starter and I had to remove the reed valve from the blanking plate as it was just too long
So now I was back to just the camshaft breather,and I started getting oil leaks from the cylinder base at the back
And it just seemed to be sweating from the rocker inspection covers and timing cover
So on komando's advice I fitted a 125 yam "egr" reed valve to the timing cover and teed that into the camshaft breather pipe
And normal service has been resumed
I guess if I blanked off the cam breather I could tell if the reed valve is doing all the work??
 
I ask because I saw the same thing. Interestingly it ran for a bit over 300 miles before its owner shut it down.

This was a "professional:" rebuild .
I did recently rebuild and engine that was built by a guy in SC. Weird story. The company I dealt with is basically a shop but doesn't do engines or gearboxes because the owner's friend is an engine builder. However, his friend has a stroke and while he thinks he's still doing a good job, he isn't. For instance, the middle ring on the right side was in the sump in pieces but the pistons and cylinder walls were fine. He had "ported" the head - ran the Dremel against one of the valve seats, lapped in the valves and called it good - you could see light though it. No circlips in the pistons. One conrod nut on upside down and one just a plain nut. And the stupidest of all - no tab washer on one side of the crank because the pin is pushed out (and doing nothing) and the nuts barely tightened.

Needless to say, they are not using him anymore.


Problem I Haven't Seen Before
 
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