Oil pressure gauge

[gwcrim]

I'm getting erratic readings from my factory OP gauge.  The engine has about 2300 miles on it and never makes an unusual sound.  When I go around turns or under hard acceleration, the pressure drops to nearly zero.  I really doubt that the pressure is dropping and I'd like to eliminate the electric gauge.

Can I retrofit a factory mechanical OP gauge into my electric gauge hole?

[JohnnyPopper]

First find out if they made one for that year.

Sounds like you have a grounding issued.

There is a product called DeoxIT D5, it is a electrical contact cleaner, I would use it on your connections.

[bd]

Verify there is not an oil delivery problem!  Connect a valid mechanical test gauge and confirm engine oil pressure during an actual road check.

[gwcrim]

The truck is a 1980 and they stopped mech. OP gauges in 1978 or so.  I agree with BD that I should verify pressure with a mech. gauge.  So if I'm going to install one, I want it to go in the original hole on the dash and leave it there.

Hence my question.

[JohnnyPopper]

Look at aftermarket to see if they span those years. I have both 78 and 80, look identical.

What is your pressure reading when you're not terrorizing the neighborhood? 

[bd]

I meant, validate the oil pressure using an accurate test gauge before investing time and money in converting the instrument cluster gauge.  FWIW, OEM mechanical gauges were abandoned in 1978 in favor of electric gauges.  The electric gauges are more than adequate, generally, being accurate to within ~7% of full-scale reading, and you aren't subject to nuisance oil leaks inside the cab or chafing of the tube where it passes through the firewall. 

As I recall, the mechanical gauges are not a direct physical fit.  Nonetheless, with determination, skill, and raw cash, anything can be accomplished.  It depends on the amount of effort you wish to invest.  There may be aftermarket conversion kits available.

Silly question, but based on a half-century of experience I have to ask: Have you checked the oil level?

[JohnnyPopper]

HA HA bd!

Reminds me of a guy who came around when I was focused on Chevy II Nova, early 60's.

He had one and was SOOO proud of his chrome dipstick.

Came around later with a knocking rod. I asked the same question- "sure, all the time!"

I checked it and sure enough, it read full! As it tapped the bottom of his pan...

[gwcrim]

Ya, I've been checking the oil level.  I guess I wanted to go mechanical because then I don't have to trouble shoot the electric gauge.   

The truck originally had idiot lights.  When I first put the electric gauge in, I used the wrong sending unit and it pegged the needle.  It was that way for a while.  Think that might have damaged the gauge?

[bd]

Nah.  That didn't damage the gauge.  The oil pressure gauge erratically fluctuating toward zero suggests that either the sender wire is intermittently grounding (e.g., chaffed or pinched by sharp metal or melted against the exhaust) or the sender is faulty.

I still recommend that you confirm engine oil pressure before chasing that rabbit, however.  It would be a shame to damage an engine because of a bad assumption.