I started to tear down the engine for my Norton 650SS,and never expected to find it in the shape it was in. Starting with the top end I pulled the head and cylinder. one of the manifold blocks just wouldn't budge so I tried to pull the studs, all but one of the intake studs came right out, and of course one in the intake manifold I couldn't get off. There were a few other studs and nuts on the valve train that wouldn't budge, so I gave them all a good soaking with the trusty PB Blaster and started blasting the cylinder. After a good once over with soda I noticed that there was what appeared to be mud dobber nests between the finns, so I grabbed a dental pick and started to pick at them to break then up. There were a few that broke up but most just fought back like baked on clay. I thought I would just change to a different media, so I dug out 40 lbs of soda from the cabinet and opened a fresh bag of glass beads. This took about an hour to change the media and do some needed maintenance on the cabinet. After I was finished I went back to check on the head. I got out a few studs and nuts off the rockers but the intake manifold wouldn't budge, I got out the torch with no avail, so another soaking with PB was in order.

Back to the blast cabinet I go with cylinder in hand, I pummel what I had thought was mud but it didn't budge, I thought about getting out the aluminum oxide but didn't want to go through the hassle again. I start looking closer and notice that the entire thing is packed with this red and black sand. top 3 fins have about 1 inch of sand surrounding the sleeve, and the center of the cylinder between the jugs and push rod tubes is solid. I get out the flex shaft and some Dremil bits and start grinding. Working on the center between the jugs only the largest space between fins was there room to fit in a small grinding stone. I get in deep and it starts to work free, just then I realize what it is, its slag and Black sand from the original 1965 casting left over that was never cleaned properly. I have never seen casting sand on anything new let alone a 45 year old part.

Several hours later ( like 4 or 5) after chipping grinding and sand blasting, and repeating several times, I have the center cleaned out. I even had to run back to Lowes to get more Dremil bits because I burnt up all my old ones. Notice the top 2 fins still have slag and sand.


When it got to be about 12 hours into the project and I still wasn't even close, I had to get out the camera to prove I wasn't crazy.




Am I crazy to go to this much effort? it lasted 45 years and never hurt anything.

It's lasted this long like that.

swooshdave wrote:It's lasted this long like that.

Yea but Im so close to finishing getting it all out, its just time and several more Dremil bits and another trip to Lowe's.

Besides I'm too much of a perfectionist and I might get another horse power out of it if it runs cooler.

I finally got the head torn down and blasted, it looks like I need a set of valves and guides at least. Black Diamond valves and NASCAR guides are in order, but should I go ahead and have the seats replaced also?

Well I gotta get back to slag removal detail, at least I only have a few hours more:)

Caferider wrote:I finally got the head torn down and blasted, it looks like I need a set of valves and guides at least. Black Diamond valves and NASCAR guides are in order, but should I go ahead and have the seats replaced also?

Well I gotta get back to slag removal detail, at least I only have a few hours more:)

Being the perfectionist can you really not get the seats done too?

Dave what are your thoughts on boring the intakes out to 32mm? If its going to the machine shop why not have it ported too.

Caferider wrote: but should I go ahead and have the seats replaced also?

)

Norton seats are fine with today's gasoline so no need to replace them. as to bigger valves and porting I would leave well enough alone just a quality valve job is all I would do.

Caferider wrote:Dave what are your thoughts on boring the intakes out to 32mm? If its going to the machine shop why not have it ported too.

32mm is probably too big for a 650.

swooshdave wrote:

Caferider wrote:Dave what are your thoughts on boring the intakes out to 32mm? If its going to the machine shop why not have it ported too.

32mm is probably too big for a 650.

My only thought is, that with the sleeve in between the carb and the port having an ID of 26mm, it seemed a little restrictive.

8 more hours chipping grinding and sand blasting, and a trip to Lowes to get the last chainsaw bits they had. The casualties from yesterday : 10 bits, flat tip screwdriver, awl, file, and sore hands.


The results were good but I still have more to do, its amazing how much slag and cast iron chunks was in there.


At leas you can see light between the jugs now.




Making progress, but still have a few spots to finish. I gotta go to a different Lowes for more bits first.

Looking nice, Keep up the great work, And pictures, Chuck.

I changed the media in the Blast cabinet, but the Aluminum oxide didn't phase the slag, it did a good job on the cast iron but I like the smooth look of the peening that the glass bead gives better. Well it's time to go shopping for High speed rotary cutters and replace a few broken tools, then its back on my head.

If Norton had been this picky with every bike sold, they would have gone under a lot sooner

Jean

Jeandr wrote:If Norton had been this picky with every bike sold, they would have gone under a lot sooner

Jean

So sad but true, I don't mind making it look like it should have. I can afford to pay more attention to detail.

I have gotten 99% of the slag removed, I couldn't leave well enough alone, while I was grinding the slag out, I just could not help myself from removing the casting seams and clean up all the areas that needed a little finishing.



I think I used every piece of grinding equipment I owned, and I also bought several new tools. Kobalt Chainsaw files from Lowe's worked well and could be chucked in the drill. The chainsaw bits for the flex shaft worked very well but were still to short to reach into the deepest spots and didn't last very long on the slag. I found this nice 4' Grinding Stone that worked very well on the slag between the Fins in all but the deepest areas, and also allowed me to easily remove the casting seams on the sides of the cylinders. the trick was to hold the edge straight and pulse the grinder for short bursts until you got it in deep, or else it would chatter and lock-up. Roloc disks on my Die grinder worked very well, but the mandrel with the thick rubber pad wouldn't fit between the fins, I had a cheap plastic one that had worn down to about 5/8 inch in diameter that allowed me to get into most of the tight spots. And then I couldn't have gotten this far without the blast cabinet and the Aluninum oxide, I will still blast it one more time with the glass beads to get the finish I want.




There is a great machine shop in town, that I have been told that their fin repair is almost undetectable.
The good news is that the original pistons were stock and the cylinder walls are in great shape and should only need to be honed, but I have plenty of room to bore over if needed.