Oil Pressure Sending Unit: Converting from Light to Gauge

[Texas82GP]

I could not find the diagram for the idiot light. But I do know that all it is, is 12 volts to an indicator bulb in the dash, and the bulb ground goes to the sender. 5 psi oil pressure opens the circuit and the light goes out. No pressure and the switch closes and the bulb lights. With the key in the "ON" position, motor not running, the bulb lights and that is known as "bulb test" mode. Hey Jared, is that a second gen Camaro I see hiding in the shadows there? NICE!

It is a second gen Camaro. My brother's that we did a 6.0 LSX swap and a T56 Magnum. It went to the painter Sunday, thanks to JAMCAR223 (James).

 

[Texas82GP]

have no worries, Jared's engine will never start with heads that have no exhaust ports.....

I don't follow. "heads that have no exhaust ports" ?????

 

[pontiacgp]

I don't follow. "heads that have no exhaust ports" ?????

here ya go, next time don't do such a great tape job that blends in the casting...

 

[Texas82GP]

OP. Its in the bottom of post 3 linking to maliburacing
- 2 separate sensors with 2 separate pickup locations. The one behind the distributor is indeed linked in with the choke. 1 line in, 2 lines out to the light and the choke. The other is down by the Oil Filter as on Jareds picture above. Not all the blocks were machined for this, if yours is not then you need to tee off behind the distributor.

Jared - please be cautious with those brass fittings. I had one let go years ago when I tee-d off behind the distributor and it broke making a huge mess and leaving me stranded. A couple of friends have mounted the sensor on the wheelwell tucked under the Master Cylinder using braided line with a 90deg fitting to clear the clutch linkage

https://www.amsperformance.com/cart/AMS-Remote-Oil-Pressure-Sending-Unit-Line.html
I am sure Jegs or Summit has something for much less dough

Perhaps I should have used steel pipe fittings. I used thread sealant and was careful not to overtighten the brass fittings. I was also picky about what I bought. I couldn't find any other remote sender kits other than what you posted, which likely has metric threads to go into the engine.

 

[Texas82GP]

here ya go, next time don't do such a great tape job that blends in the casting...

Got it! That's funny!

 

[MrSony]

It's going to take a guy with an unmodified setup like ed1948 to comment on how they were setup stock. My car was a diesel, but it had a gauge. The wiring is very different from the gas engine harness though. I suspect that the stock SBC setup was as I described above, with the switch in the port near the distributor for the light and with the sender in the port near the oil filter for the gauge. Having the sender near the oil filter can be a problem for mechanical clutch linkage but since none of the cars past about 81 had manual transmissions, this isn't an issue. I overcame it with brass fittings, since I will be running mechanical clutch linkage.
View attachment 62575

I just can't get over how purdy that engine looks.

 

[FL85GrandPrix]

Thanks for the help guys. I looked at the schematics this evening at home and it makes sense. However, i checked tonight.... my car has 2 wires that provide the 12V, not one. I have 4 total wires that plug into 2 spades. I'm guessing the 20A circuit is split? Who knows.

 

[Texas82GP]

Something else is likely sharing the power source.

 

[Texas82GP]

I wonder if the extra wire is for the choke light on the dash?

 

[Bonnewagon]

Jared! COOL car! We don't get rust free F bodies around here. OP. This is on an '85 GP? Are you swapping in Pontiac factory gauges or aftermarket? The reason I ask is that, unlike other makes, Pontiac was very good about the wiring connector at the back of the gauge pod. The wiring is identical for both idiot lights and gauges. So you can convert to a factory gauge pod and just pop in the connector. You will be good to go. There is even a white wire for the tach stashed away in the main harness too. Let me look in my '86 factory manual and see if I can locate the problem wiring for you.