Good idea.
IF (big if) the switch is not defective then original bulbs (type 5400 according to the GMC Maintenance Manual and which no longer exist) or 6012...
If you are talking about a standard H6024 7" bulb, they only use 40 watts. Regular incandescent bulbs take more. I put 7" reflectors that use...
I'd buy one. Here is one from Summit Racing Summit RacingĀ® Piston Stops SUM-900189 It needs to thread into the spark plug hole and be...
A piston stop is basically a bolt with a rounded tip. It screws into #1 spark plug hole. The tip of the bolt extends slightly into the cylinder....
You could find a place to mount a pointer near the balancer, use a piston stop to determine TDC and then scribe your own mark on the balancer.
215/85R16 would only decrease RPM by 10%. Probably not worth the money.
What size rear tires?
The 55.2-59 GMC Maintenance Manual shows a 4A fuse in the light switch that protects the dash lamps. I think the Chevy is the same.
Possible that the armature has a dead spot. Also possible that the starter solenoid is the cause of the problem. Put a test light on the big lug...
Good diagnosis Paul.
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