Damn Oil Pressure

[MustangPaul]

Hi there--

I've been having problems with the GT using oil. I know I have one, possibly two bad rings. Ok, the latest is that at a constant speed, the oil pressure will drop from 3/4 across the gauge where it usually rides to between 1/4 and 1/3 across the gauge. Just changed the oil yesterday with 10/40. The waggling pressure makes me nervous.

Ok, as I see it, it could be

* Bad Sender
* Bad Gauge
* Bad Wiring
* Bad Instrument Panel Voltage Regulator
* Dying Engine (I don't want to think about this one.)

What order would you tackle these? I'm thinking of checking the wiring, getting a new sender and see what that does. Then the Volt. Regulator. Then getting an aftermarket gauge to see if mine is bad.

If I get an aftermarket gauge, electrical or mechanical? I'm no wiring ninja, so it'd need to be simple.

How would you attack this? (Yes, I know I need to rebuild, but with a 2 year old, that isn't in the cards yet.)

--Paul

 

[65fastback2+2]

merchanical ones are alot easier to put in, you could even put it in temp to just check things out, it would solve everything really, if it still jumped then the motor, if it didnt then its your other oil guage. Id just put in a new sender first, if your other guages work fine, i doubt its the volt. regulator

 

[MustangPaul]

merchanical ones are alot easier to put in, you could even put it in temp to just check things out, it would solve everything really, if it still jumped then the motor, if it didnt then its your other oil guage. Id just put in a new sender first, if your other guages work fine, i doubt its the volt. regulator

65--I think that's what I'll try. Will the mechanical sender fit onto the "stalk" that the stock sender screws into?

 

[MustangPaul]

Put a new sender in today and noticed that the oil pressure is not reading as high as it was. (I take this for a bad sender.) Now the fuel and oil pressure gauge wiggle, slightly, in unison. The Instrument Panel Voltage Regulator is the next fix. While I have it out, I'll go ahead and repaint the needles and such.

 

[snowball]

It could be that the oil you've used is a different grade than you used previously. 10/40 seems a fairly thin oil to me. When I used a 15W/50 grade oil, my oil pressure needle stayed below half on the guage (quite worrying), but when I changed to a heavier grade oil - 20W/50 the needle went back to its normal reading. With bad rings this could also pull the readings down.

My advice is - go back to a heavier grade oil.