A while back I mentioned to this list that my oil pressure gage was was
acting odd. Well after trouble shooting, such as testing the oil pressure
gage, testing the pressure from the engine block and replacing the sending
unit, I finally found out what the real problem was. It was the grounding
wire that connects to the back of the oil pressure gage. Corrosion had
built up on the copper plate on the end of the grounding wire which resulted
in a gradual poor connection. This caused the oil pressure guage to give
off periodic inaccurate readings. The most common problem was that it would
start off reading fine but slowly drop and on a few occasions drop to zero.
I cleaned the copper plate off with fine sand paper and reconnected the
ground. After doing this the guage was reading normally again. So far I
haven't had any problems since.
Darrell