Durango_Boy

Are there resistance differences between the '77 oil pressure sender and the '82 oil pressure gauge? I thought I would just replace the oil pressure sender with one from an '82 since I have '82 gauges but the '82 sender is a switch as well and won't work with my '77 wiring.

I don't mind using my '77 oil pressure sender since I just bought it new a few months ago but I want to make sure it's not indicating a big difference because maybe the sender and gauge don't have matchign resistance.

chevr0letman

Got an ohmmeter? Easy check.

Durango_Boy

I didn't want to buy the $45 sender just to check resistance...since it's not just a sender it's a switch probably a fuel pump shut off switch.

V-Twin

Why won't the 82 sender work? it has 3 terminals, 2 are for the pressure switch, one for the gauge. There are 2 parallel blades, the other one is perpendicular to the other 2. That's the sender signal. How difficult can it be to leave 2 of them off and only use the middle one. Maybe even use the stock boot, just remove 2 of the wires.

Durango_Boy

I considered that but if there is no difference in resistance between the senders...as in an inaccurate reading, there is no reason to buy the $45 sender instead of using the new $9 sender I have. If there is a noticeable difference then I would consider that an option.

The '82 senders are very expensive. I picked up one of the oil temp senders and it was almost $50 as well.

bmotojoe

If you’re using the 82 gauge what color tab is on the ceramic resistor attached to the 82 gauge? I think the 77 gauge has a pink tab on the ceramic resistor. It may through off the accuracy some if the resistors are not matched to the sender.
Something to think about.

Durango_Boy

Here is a pic of the back of my '82 gauges. Can the ceramic resistors be bought individually from a vendor? I have no experience ordering or replacing them.

bmotojoe

Do you have the gauge set from your 77? If the hole centers are the same on the ceramic pieces can’t you just swap ceramic resistors to what you need?
I’m not sure where the location of the oil pressure gauge is on the 82,,,lol
I have never looked for resistors on any vendor sites so I don’t know.

bmotojoe

The resistors should be typical throughout the gauge cluster and should be matched to there corresponding switches, fuel, temp, volt etc.

Durango_Boy

I didn't ever have the stock gauge set for this car. When I bought it had a set of digital gauges and I removed it in favor of analog gauges. I went with '82 gauges because I wanted the oil temp gauge.

The oil pressure gauge is middle on the bottom row.

bmotojoe

This picture is of the back of a 77 model. Top gauges Temp & Fuel orange. Lower gauges clock none, Oil Pressure pink, Volts blue.
Hope this helps,

markdtn

All C3 oil pressure gauges use the same resistance in the sending unit. 73-81 use the same sending unit. An 82 has a different sender because of the built-in fuel pump switch.

chevr0letman

Its not as fast as the Bugatti Veyron.

Durango_Boy

Thank you...that's exactly what I was looking for.