73 frame 74 Engine Commando 850. First Start Since 1991 Thanks to Many of You

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I just want to make sure the new oil is making to the engine after filling the tank. The only way I habe learned to change the oil ir remove the drain plug from under the engine, drain the old oil, then fill the tank (behind the right side plate). Which is very new to me I have always just filled engines with oil at the engine.
Mark, I bought the factory service manual from Andover Norton and Norman White's Commando restoration manual. I also researched topics on here. I am sure, if you understand period British twins, the Commando is fairly predictable and straightforward, with a few peculiarities. If, like me, you're new to them, the manuals are the start point for diagnosis and working out what to research and which questions to ask on here.

Brilliantly, as a consequence of this approach, I've managed to do far more than I imagined I would. My bike is now running sweetly, I understand it better than any bike I've owned previously and we've bonded! :)

Apologies if you know this: The oil tank is behind the RH side cover. It has a drain plug, which removes most of the old oil. Some oil also sits in the sump, having drained but not yet been scavenged by the oil pump into the tank. Also, over a matter of days and weeks, gravity pushes some oil from the higher oil tank, past the oil pump in the engine case and into the sump ("sumping"). So, sump and oil tank need emptying for an oil change. My 850 has:
a) 2 filter screens, one in the tank, one in the sump, which need cleaning.
b) There's also a screw on oil filter to replace, housed in an external unit down low behind the engine, in front of the rear wheel. This needs replacing.
- There's a thread on here showing testing and ranking of various engine oils.
- To check the oil is circulating, after a change, with the seat off, oil tank cap off, the return from the oil tank is visible. It pulses a little, but should be fairly constant and not frothy. Flow rate increases with rpm. Unless you suspect you are not getting oil pumped to the head, that should be good for peace of mind.

Section K of the service manual walks you through all the regular maintenance jobs (quite a lot of them!), along with a maintenance schedule. It x-refs to other sections of the manual, where more detail is provided. I find it really helpful, then a quick search here, or a question answers anything I've not understood. As a result, in 6 months, I've graduated from blind beginner to enthusiastic novice :)

Apols again if this was obvious. Enjoy!
 
Thanks guys. When I got the bike the oil tank was empty. All I have done is drain the engine oil (was black almost) then fill the oil tank. I will try yalls advice!
 
The oil tank was empty because after sitting awhile it had drained or 'Wet Sumped' into the crankcase.
If the Norton is run or started regularly, this won't happen.
 
This is for 35351 as it isn't the same as the original Lucas switch.

Edit:
T1 - Brown/Blue
T2 - White
T3 - Brown/Green and Blue/Yellow
T4 - Not used
 
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This wiring harness. Original harness. I can't tell which end goes to the front because I have no diagram. There are wires that come off the main and are pointed (taped) to where they point towards one end if that makes sense. Do the tilted parts need to point towards the back?
 
This wiring harness. Original harness. I can't tell which end goes to the front because I have no diagram.

73 frame 74 Engine Commando 850. First Start Since 1991 Thanks to Many of You


Section J, Fig. J11.


The front end of the main harness has the largest cluster of wires containing (amongst others) the following:

Purple/black PB
Blue/yellow UY
Light green/brown LG/N.
 
This wiring harness. Original harness. I can't tell which end goes to the front because I have no diagram. There are wires that come off the main and are pointed (taped) to where they point towards one end if that makes sense. Do the tilted parts need to point towards the back?
Did you get the schematic I sent ? Lay the harness out and puzzle a few of the colors out to see which end goes which way . tail lamp leads will tell you which end goes to rear . Remember that everything stops short of the headstock because you need the headlamp harness beyond that . Look for the Zener diode leads - they will go down to z plate. Don’t start tying things together until you have the orientation solved .
 
You have it AAF in that pic.
 
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What is that sorry

Arse About Face.

Fold masking tape over itself on the ends to make a tag.
Write what it is on the tape based off the wiring diagram with the loom laid out on a table top (not the floor)

If it is a modern loom which it looks like it should have minimal wires, running things like a modern R/R might have some bearing on things like the Zenor wiring etc but nothing OTT.


This below (your pic edited) would give you a start with some items now marked.

kvGOyLuk.jpeg
 
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Going nuts here. I can't figure out which is front and back with this harness and I'm sure some wires are not needed.

Lay the harness along the backbone of the frame . Find the leads for the coils - two on each side . The schematic I sent you will tell you the colors . Just guessing it looks like the end in the bottom of the picture is the front because of the number of ends but not
sure - see if the tail lamp leads are at the back end . There should be a branch that goes down to the Zener on the Z plate . If these three clues show that all will reach then proceed. If not turn it around and try again.
 
I had forgotten about this Grant Tiller drawing. (modified) Lucas source)

Any job that is not that exciting (sorry electrical vocation folk) needs to be easy I think to build some excitement.

corrected-3.png

OP Mark Deaton looks to have not signed in since last month so hope is still not out in the garage.
I have unwrapped (tape) my new loom and ready to start adding and removing wires from it, what could go wrong......
 
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