fuse blows when ignition is attempted

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davidcharlton

fuse blows when ignition is attempted

Post by davidcharlton »

This is one for all you bright sparks. Completion nearly achieved, all the electrics work but when I turned on the ignition and earthed one of the spark plugs hoping for a big fat blue spark, instead the fuse blows, It seems like what ever's causing it to blow is drawng a lot of power vertually draining the battery, any and all suggestions appreciated, David
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BAZ
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Re: fuse blows when ignition is attempted

Post by BAZ »

Unplug the alternator and see what happens.
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KETTLE BOY
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Re: fuse blows when ignition is attempted

Post by KETTLE BOY »

Take the tank off, and check, the connections on the coils. Dissconect that coil, Then try it on the other two. Then if that's not blowing the fuse, connect up that coil again, and if it blows, that's your problem? Could be a bad coil, shorting to earth. Good luck.
GT750 J 1972
GT750 L 1974
Z900 A4 1976
ZZR1100. 1998
Breville Sandwich Maker
I'm never wrong.. Once I thought I was, but I was mistaken.


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yeadon_m
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Re: fuse blows when ignition is attempted

Post by yeadon_m »

Hi David,
+1 on what Baz advises. I recall 'Dan Hatfield' posting on the US GT Yahoo group extensively on problems just like yours. He points out that nothing thats working properly on a Kettle is capable of drawing enough current to blow the fuse. So it must be something odd in the wiring and if for example you just played with the alternator (one of two top candidates for high current draw when defective) my bet is its that. Simply disconnect the plug under the left side panel and see if the problem goes away. If so, and if you have moved the wiring to it, that will surely be the place for a fix.
The only other viable alternative will be a wire whose insulation has rubbed away so that you have a straight short. These can be a PITA to find, but made easier by finding hot wires and worse, melted insulation - so take the tank and panels off, open the headlamp and feel for what gets hot when this is happening.
The momentary turning of the fan isn't a problem - mine used to do that and its a small current draw anyway.
Good luck!
Mike
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davidcharlton

Re: fuse blows when ignition is attempted

Post by davidcharlton »

Well done to those who said it was the alternator. I had done something stupid, hooking up the cable from the points to the alternator connector. It had been so long since I had completed the wiring, I forgot to check the two 4 spade blocks which can be interchanged, well dony lads!!, not so well done me!
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yeadon_m
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Re: fuse blows when ignition is attempted

Post by yeadon_m »

Hurray - good news, Mike
ps: I only got my info from others, so the credit is Baz's and Dan's (in absentia)
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