Fitting N15CS engine

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I’m about to fit a newly rebuilt engine to my N15CS. If I fit just the engine first on its own, can I fit the gearbox after the engine has been fitted? Or do I have to do it all together ?
 
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I don't know but am interested in finding out! Would love to see pics too. I am about to embark on a '66 N15CS project. GrandPaul will know I'm sure.
 

texasSlick

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I think (think means not absolutely sure) it must be done as a unit. I have a book at my shop which shows the G15 or N15 engine removal/refit procedure. Will look it up and post here in a day or two.

FWIW .... According to the Norton Manual, the Atlas must be done as a unit.

Slick
 
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As it is the same frame as my AJS 650 CSR it may be similar in terms of fitting the gearbox. On mine I could only remove / refit the 'box by removing the outer & inner gearbox covers. It will then twist around enough to come out. I realise the engines are not the same but they are similar in size & shape.
Hope this helps.

Martyn.
 
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I’m about to fit a newly rebuilt engine to my N15CS. If I fit just the engine first on its own, can I fit the gearbox after the engine has been fitted? Or do I have to do it all together ?
I think I’ll fit it as a unit, and get one of my strong mates to help me put it in...
 
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Not sure if it would work on a Norton as I've never fitted an engine on one yet, and it looks challenging - but for my big Japanese 4's (CB750, GS1100) I lay the bike down on the side and use a hoist to lift the frame off and back on. So I mount the frame to the engine. I am able to do it solo with no scratching of my freshened up engine and frame every time. I wouldn't need a hoist with a 2nd person but it is nice to have that fine adjustment.
 
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You cannot fit the grarbox after the engine because you will have no play to fit the bottom stud.
 
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Fit gearbox first, with one rear cradle bolt,so that you can jack it up to fit the lower engine bolt. Then engine. Front plates last.
 

texasSlick

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Per Norton Twin Cylinder Service Manual:

Engine and gearbox are removed/fitted as a UNIT.

Basic Instructions for removal; reverse for assembly.

Remove fuel tank, exhaust pipes, carburetors
Remove tach drive, clutch cable gear box end, then the engine plate cover over gearbox.
Remove breather and oil lines.
Remove rear chain connecting link.
Remove right side foot peg with its rod, from the left side.
Remove all bolts passing thru the front engine plates - loosen the nuts only on the bottom one only (taken verbatim from manual).
Remove spring for center stand with the stand in the up position.
Remove the nuts on the left side of the rear engine plates - then take out the bolts.
Lever the engine upwards - then loose nuts on the lower bolt can be taken off, as well as the engine plates.
Move the engine forward - lift up - and out of the frame.

This is the Gospel from Norton, but Ludwig's method should work.

Slick
 
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My Clymer manual has a couple of pages on this for the N15CS and one pic, if you want me to scan it let me know via PM.
 
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I managed to get the engine and gearbox in together by lying it on its side, and placing the frame over the top of it.
It didn't take that long really, and I managed to get it all in without damaging the frame paintwork, which is what I normally do when I fit an engine to a frame...
 
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Pics? I need inspiration on mine... Well, I really need a triple tree.
 
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Never had my N15CS's motor out, but recently read somewhere that the center stand is difficult to impossible to mount with the motor in place. So, if you plan to have a centre stand, you might do well to make sure it's on BEFORE shoehorning in the power plant.
 
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