1975 Norton - Engine Rebuild
This is a long story. I originally sent my engine parts off for machining, but due to unfortunate circumstances, the work never got done and I got my engine back after many months. I let it sit for another 3/4 of a year and tried again. This time, with more success, but it still took 6 months to get everything back. It was worth the wait - Jim Comstock in Colorado does amazing work and everything came back like jewelry.
Starting with the crank and rods, then setting up the end play, add some sealant and bolt 'er up. To set up the end play, I used an old set of main bearings that I ground the OD and ID such that they just slip on. That way I could try various shims without having to heat up the cases each time. For final assembly I, of course, heated the cases to install the new bearings.
Next was the timing chain. Along with that was torquing the crank and cam nuts with a cut away cover in place.
Next up was the pistons and cylinders. I used the "Comstock Method" to compress the rings and assemble the pistons and cylinders. (See www.accessnorton.com/NortonCommando/installing-barrels-with-two-hands-and-no-ring-compressor.24859/) Worked great!
I had an oil pump around that looked pretty good and I rebuilt it. I noticed, however, it was for an older style outlet with the smaller diameter output flange. I had to file a bit more of it flat to get the flange to sit square.
I then installed a Comstock cam chain tensioner, checked the cam lobe timing and put together the rockers. (See norton-rocker-spindle-fix.html for more rocker fun!)
Mostly together (the head is not fastened - I'll do that after I get the block in the frame.
It's starting to look like something!
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