Might wanna know this -- I'm glad I'm pretty, 'cuz I'll never make it on my smarts.
My oil pressure light was intermittent since about the end of the big cross-country this fall, and I was getting kind of used to it coming on with 40 lbs. in the case. I have a backup in the engine compartment, a little Mohawk gauge, so I wasn't going to screw with it until spring. Nonetheless, I went and bought one, and I was getting kind of tired of looking at it in the middle of the dining room table, so I decided to change it out.
Ordinarily, I don't think oil pressure switches fail and turn on the indicator light. If it's grounded to the case, like this one was, it should fail without doing its job of lighting the indicator. In my case, this old unit had a ground wire that went to the case right behind and below the oil fill; it was a ring connector on a stud, with a self-locking nut holding it on. It failed because the nut was loose and the road grime and wind from the fan were knocking it around.
The bad part had two prongs and was the type of doughnut connector that takes a small machine screw. I tossed the ground wire with the bad unit, and made a new slot-connector for the new one with the old power wire. Not at all difficult.
The replacement is internally grounded and only has one wire. I replaced the unit in about fifteen minutes, going right down the top of the case and without having to mess with the distributor. Fairly painless, but I thought I'd add to the corporate knowledge.
The replacement part was about six bucks. Cheapest part yet.
Pardon the crummy photos. Camera phone.
Original Post
