1974 Norton Commando engine bottom end rebuild, Part: 2 Bottom end disassembly

In this video, We do a descriptive approach on the disassembly of the Norton 850 engine bottom end and talk about the parts and inspect the parts. We then decide what to do going forward. I hope you enjoy this inside look of a Norton 850 engine.

[@SEPTIKANGEL]

Have a Commando with a leaking head so watching with interest Jesse, you're both making the videos very interesting and helpful, thanks!

[@jessesvintagegarage765]

Thanks,

[@howardmerkley2245]

Maybe look at Jim Schmidt's video [JS Motorsport] on the subject too. Annealed copper gasket. ruclips.net/video/TUnQg2TNWHQ/видео.html

[@SEPTIKANGEL]

@@howardmerkley2245 Thanks Howard.

[@howardmerkley2245]

@@SEPTIKANGEL YW .. My pleasure !

[@TornadoCAN99]

The composite gasket is supposed to seal better than the copper, but needs multiple rounds of head bolt re-torquing. Typically, first run, stop & re-torque within minutes. Then at 50/100/200/500/1000 miles. Always use an accurate torque wrench on all the bolts and follow the torquing sequence in the manual . A standard socket or torque wrench cannot fit/reach the two front lower sleeve nuts and rear center stud nut.... I use a right-angled spanner-to-torque wrench adapter (Motion Pro sells it in the USA) to allow use of a torque wrench held at 90 degrees to the spanner wrench that fits on those nuts (7/16" I believe). As long as you keep it at 90 degree, torque setting on wrench will equal torque at the nut.

[@BobMatthews]

Worn main bearings normally make a rumbling/grumbling sound.
A knocking noise is usually the big ends or the little ends to a lesser extent (but that doesn't seem to be the case here) or the pistons hitting the head. Have you tried a squish test with some soft solder just to check what the clearances are between the pistons, head and valves? I wish you good luck with the rebuild and hope you get it sorted.

[@TornadoCAN99]

How many miles on this engine since last rebuild? The knocking noise may have been the outer primary case contacting the engine cradle at the rear end of the case. Or perhaps the exhaust header pipe contacting the primary cover right near where the header pipe bends up towards the silencer connection. My '74 850 was doing this after I changed the header pipes out to non-balance pipe types. Guess they are slightly different shape than originals.

[@jessesvintagegarage765]

That top end had less than 400 miles, part 4 comes out Wednesday 7/20/22 and we install the bottom end and assemble the primary, we come across a couple interesting things, including the inner cover contacting the swingarm it will be interesting I'm sure you will enjoy what we discover

[@Dyna3f604]

what happened to the triumph you rebuilt? Never saw it running did the engine start?

[@jessesvintagegarage765]

Oh, its coming up

[@jessesvintagegarage765]

To be honest, I just got the video all together, so look for it Thursday 6/23/2022