Testing spark plugs

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Baz
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Testing spark plugs

Post by Baz »

Hi, I am having a problem with my NC30 not starting. It has been stood for about 3 weeks but I used it daily before that. It turns over fine but does not even attempt to fire. I have checked fuel is coming through the fuel tap and thought I would test the plugs for a spark before stripping down to the carbs. This is my first NC30 and I know the electrics can be a little temperamental so I thought I would just check before diving in, is it ok to just undo a plug and lay it on the engine, turn it over and check for a spark? This might be a stupid question but I would feel even stupider if I did it and damaged something!
Andy666
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Re: Testing spark plugs

Post by Andy666 »

Keep them well away from the spark plug wells, you wouldn't want it igniting the fuel as it gets forced out the open hole. Hold the plug somewhere like the frame, somewhere with a bit of distance :peace:
Baz
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Re: Testing spark plugs

Post by Baz »

Cheers mate, I didnt think of that.
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CMSMJ1
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Re: Testing spark plugs

Post by CMSMJ1 »

get them out to have a look at them - they will spark out of the engine even if they are too shit to get it running under compression.

See how wet they are...get them on a gas hob adn burn the shit off them - they get hot
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Baz
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Re: Testing spark plugs

Post by Baz »

back ones are out and cleaned. (There was only a bit of crap on them but they were wet). Just having a cuppa then starting on the front ones. Does the upper rad have to be moved?
If they are wet does that mean its running too rich or lean? I did the carb mod a couple of months ago and set everything up as in the guide on here (awesome instructions by the way) and it all seemed ok and ran sweet but wonder if that might be related to the problem i'm having???
Baz
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Re: Testing spark plugs

Post by Baz »

I tested the plugs and there was a very weak intermittent spark. Could this cause it to not even try to fire at all?
Do you reckon it is knackered plugs or could something else cause this? I am a bit skint at the moment and if I buy new plugs and its not that then I cant afford to buy anything else until next month.
hunter
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Re: Testing spark plugs

Post by hunter »

Throw them as far as you can,And get some new one's
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Neosophist
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Re: Testing spark plugs

Post by Neosophist »

how did you try and start it after it was standing?

my bet is the plugs have fouled and knackered
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CRM
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Re: Testing spark plugs

Post by CRM »

slacken the top rad and tilt forward with the panels off. you can just get to them this way and you will get a bit of "NC rash" where it scuffs your knuckles rubbing against the rad lol.
if you had the original plug spanner from honda in the tool bag it makes removing plugs much easier.

anyway clean all 4, use contact cleaner or brake cleaner and leave to dry before putting them back in.
full choke and NO throttle and crank her over. once fired leave it to get nice and warm before stopping it this is what often fouls plugs, people going to the garage to start it for a few seconds, quick rev then off.
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