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dwcsr · 10-19-2009, 08:17 PM

I would change the timing up or down a few degrees and adjust the throttle accordingly. See if the miss fire changes rpm. That would let you know if its carb or ingnition or valve train. If it stays the same then Its either ignition or valve train. If it changes its carb. if not back off the rockers 1/4 turn and check again. If it changes its vales or adjustment
If its still there its ignition.

Test the wires with an ohm meter.
Check that the gap is .035 for points or .045 for electronic.

Put a vacuum gauge on it and see if the needle bouces. If so its a valve issue.

10-19-2009, 08:17 PM	#5
dwcsr Hollister Road Co. Join Date: Apr 2005 Location: Houston Posts: 6,131	Re: misfire I would change the timing up or down a few degrees and adjust the throttle accordingly. See if the miss fire changes rpm. That would let you know if its carb or ingnition or valve train. If it stays the same then Its either ignition or valve train. If it changes its carb. if not back off the rockers 1/4 turn and check again. If it changes its vales or adjustment If its still there its ignition. Test the wires with an ohm meter. Check that the gap is .035 for points or .045 for electronic. Put a vacuum gauge on it and see if the needle bouces. If so its a valve issue.