Good point Jon G. If a person adds another bulb to the old system of rear only, it would change the resistance/current draw and fast flash. Maybe rick can post the flasher PN if it's still visible on the flasher can. Then we can all check that out and guide him to a different one to try. The flashers are kind of a specific design for a certain system. The strip has to heat and cool under a fairly precise load.
For Reference: The no.1 cause is bulbs. A person could experiment and take one front bulb out and test blink. Compare speed to the other side.
Rick: You have great patience to last over 30 years with fast flash. Is there a chance it is "normal" since there is no way to know what normal is for a 1939 Chevy? Is it strobe light fast/hyper fast............ or kind of fast compared to something?
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
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