75 MK3 no spark

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Hey everyone im new to the site and the Norton Sean all around. I have recently gotten my fathers mk3 due to it sitting in the garage for years and never ran. Trying to get it started iv pulled the duel amals and cleaned them up, new plugs, wires, oil and filter. Hoping it would now kick over iv found it has no spark, iv been told it will start with no batt and at the moment i dont have one and the starter is not in so i need to kick it. Im at a loss at the moment to why it wont start other then the condensers and or coils to the best I know it ran when it was parked. So now what im looking for is some advice to get it running and on the road. The other thing is if theres anyone local to my place who knows nortons well and wouldnt mind spending some time working with me on it getting things dialed in it would make my day, I dont have any pics at the moment but i will put some up. Any advice thank you.
 
Welcome to the forum!! First i think it would be in your best interest to get a shop manual. You do need a battery and remember it is a positive ground system. Cj
 
My oh my, where do we start.

First off, in order for the bike to start without a battery, everything will have to be as good as possibe. The second is that MC capacitor needs to be in top notch condition. If, and I do mean "if", all is set for proper operation (good gas, carbs tune to perfection, ignition proven, sound and timed to the tee, etc, etc) you will still have to kick the ba-jesus out of it to get some charge from the assumably good stator, rectifier and zener and then into the capacitor to offer up a glimmer of spark to ignite a perfect blend of air and gas to achive what one might concider a success, a "piff" much less a pop from one of the exhaust pipes.

Otherwise, go get a battery.
 
Its possibly the electricity . :P

2 Mc , you swing it through first , key off , twice , to charge the capacitor .

The capacitor would discarge , ign. on .

SO , starting it 's a bit like a Magnetto . Damp (tickle) from cold . Pulling it trough twice , to prime the cylinders ( 4 compressions )
will have charged the capacitor .
Throttle cracked open a notch or two at the most , for good fuel draw , and catch it on the throttle .

IF its got the std. points / contact breaker ignition . Inspect the points to see the gaps clean .

Youd save youreself a bit of bother , hooking a car battery with jumper leads , to test the points spark , at least .
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Ran mine , no battery , ever , Mk II Amals It WOULD NOT start , un primed , as in Chokes On if the weather was cool .
Needs to be damp , but not flooded . Throttle opened off stops , but not far. Throttle wiggled to catch , at 2000 rpm youve got it .

Pay to give the connectors a dose of CRC , and a wiggle or tug to see the bayonet fittigs are firm .
If theyre at all loose , youre out of luck. Typical detail is to ' coustom fit ' the grip of them all .Squeeze a iota with pliers to get good contact .
Bound to be a bit off resistance from disuse , so the CRC trip saves grief , & in the rain .

Dont rev the snot out of it cold . Pouring a little oil into the valve gear would do no harm .
 
I used to run mine all the time in the 70's with just the MC2, but after a while it wouldn't start. I could see spark kicking it over, but was not enough. Probably the rotor was loosing magnetism and the MC2 had gone south. Get yourself a battery, even if it's just a 2AH, remove the MC2. Can you put your location in your info? Might help, if you're close buy I'd help. These bikes are not magic.

Dave
69S
 
Hey guys thanks for the input, so i do have some manuals iv gotten from online and some good notes to read, I agree about getting the battery and I will next chance I get.
Iv got new gas in the tank, iv tickled the carbs, cracked the throttle and kicked like a mule.(No go) I do need to check the points, I didnt because I was hoping they were set well but did not think about them being clean so ill do that also.
Lastly im in long beach CA sorry I didnt put that in before, and as always thank you for the help
 
Matt Spencer said:
2 Mc , you swing it through first , key off , twice , to charge the capacitor .

The capacitor would discarge , ign. on .


The 2MC will discharge in less than a second when the ignition is switched on again, so theres's little point in attempting to "prime" it, as it will have discharged before you had taken your fingers off the key.
 
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