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Misfire.... HELP!!

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Old Feb 20, 2006 | 03:41 PM
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Default Misfire.... HELP!!

I have a 1980 C3 350cu 4sp.

A week ago after starting it from hot it developed a misfire. I suspect heat soak has damaged the coil. Is there anyway I can diagnose whether it is the coil causing the problem before I go an purchase a new coil?
The other idea I have is a sticky valve but I don't want to go there just yet!!!
Also the car seems not to be holding charge. I suspect the alternator isn't charging the battery. Do you know how I could check the alternator is charging the battery???

Any help would be greatly appreciated!

Thanks
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Old Feb 20, 2006 | 03:51 PM
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for the coil use a ohm meter it should read 0 or almost 0. for the alt. using a volt meter it should have an output of at least 13.8 volts
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Old Feb 20, 2006 | 03:54 PM
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Thanks pal

Where would I measure across on the coil?
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Old Feb 20, 2006 | 04:19 PM
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across the two primary terminals that look like this _ _ not l l l.. one the cap facing the drivers side . the other test is remove the cap , put one lead on the high tension terminal and one lead on each primary .if both reading read infinate repalce the coil.. right from the book.. infinite means the pointer goes all the way to the end..
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Old Feb 20, 2006 | 04:23 PM
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I used some additive I found on the fourm . put it in the tank and poured some down the carb It was supposed to clean and free sticky valves.. I get you the name tomorrow..great stuff
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Old Feb 20, 2006 | 04:27 PM
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Originally Posted by palazzopl
I used some additive I found on the fourm . put it in the tank and poured some down the carb It was supposed to clean and free sticky valves.. I get you the name tomorrow..great stuff
Transmission fluid? That's what old timers used, at least...

Is it misfiring or backfiring?
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Old Feb 20, 2006 | 04:29 PM
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It's misfiring badly.... to me I'm thinking it's electrical but someone has told me it could be a sticky valve...
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Old Feb 20, 2006 | 04:31 PM
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hows the timing
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Old Feb 20, 2006 | 04:35 PM
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Well you could try transmission fluid down the carburetor and hope that cleans out the valves...
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Old Feb 20, 2006 | 05:14 PM
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Timing probably needs checking as well but the strange thing was it actually started misfiring when I restarted it when hot... I'm going to check a few things tonight;

timing
coil
ground points

Thanks for you help.. what do you think?
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