Replace idiot lights with gauges.

[imjohnny]

You replace the oil pressure switch behind the distributor with the ps154,leave the switch on the block alone.

Awesome. Ok. I saw some guy had that switch screwed into the port above the oil filter and looked. I have a hole there that looks like it has a small plug in it. Was just making sure. Looks like I already have the temp sensor that is required for the gauge in block. It looks like it is inbetween the spark plugs in cylinder 1 and 3. Am I looking in the correct location? What about voltage. Is there anything I need to do for that gauge to work or will it just read the signal it already has?

 

[Ricko1966]

The oil pressure sender is behind the distributor.

 

[imjohnny]

The oil pressure sender is behind the distributor.

Thanks so much.

 

[AyWoSch Motors]

@imjohnny

I have about 7 or 8 hole gauge sets, cluster, housing, face plate, etc, as well as many loose gauges. Early 70s, late 70s, and 80s styles.
If any of that would help you in your quest to upgrade, let me know.

 

[Ricko1966]

Your gauge cluster will get power from the fuse box O.P. ,Fuel,and temp will ground through senders to give you different readings. Do you have a volt gauge or an amp gauge?

 

[75gmck25]

If you already have a sensor for the temp light you will need a different sensor for the gauge. The warning light sensor is just an on-off switch. Finding the right sensor may be more difficult than you think because GM changed the resistance profile over the years. They are all 0-90 ohms, but the resistance that matches 1/4, 1/2,3/4, etc differs between sending units.

For example the original Delco sending unit for my ‘75 is no longer available, so I only found more expensive aftermarket reproductions online. But I was eventually able to find a standard sender at Autozone that puts the needle at just below mid gauge when the truck is about 185-190 degrees (my gauge is not marked in degrees).

 

[imjohnny]

Your gauge cluster will get power from the fuse box O.P. ,Fuel,and temp will ground through senders to give you different readings. Do you have a volt gauge or an amp gauge?

Voltage

If you already have a sensor for the temp light you will need a different sensor for the gauge. The warning light sensor is just an on-off switch. Finding the right sensor may be more difficult than you think because GM changed the resistance profile over the years. They are all 0-90 ohms, but the resistance that matches 1/4, 1/2,3/4, etc differs between sending units.

For example the original Delco sending unit for my ‘75 is no longer available, so I only found more expensive aftermarket reproductions online. But I was eventually able to find a standard sender at Autozone that puts the needle at just below mid gauge when the truck is about 185-190 degrees (my gauge is not marked in degrees).

Yeah I am seeing that. May be a bit of trial and error I guess.

 

[Galane]

I upgraded a 1982 from the idiot lights to the one with gauges. The connectors were the same but I had to get the diagrams for both clusters and move a bunch of wires around in the plugs to make things line up. There are little tabs on the contacts or in the plastic connectors that have to carefully be disengaged with a small tool then the wire slides out and will snap into its new place.

The wires for the idiot lights then just need the gauge sensors installed on the engine.

 

[imjohnny]

I upgraded a 1982 from the idiot lights to the one with gauges. The connectors were the same but I had to get the diagrams for both clusters and move a bunch of wires around in the plugs to make things line up. There are little tabs on the contacts or in the plastic connectors that have to carefully be disengaged with a small tool then the wire slides out and will snap into its new place.

The wires for the idiot lights then just need the gauge sensors installed on the engine.

Yeah, I figured I would be repining some of the connector. Where did you get the pin/wire info at? Can't find it.

 

[imjohnny]

The original oil pressure gauge in a ‘77 was probably electric. Is the oil pressure gauge in the ‘76 cluster electric or mechanical (mechanical would have a fitting on the back for a hard line)?

If they both were wired for electric gauges it may be plug and play. You would need sending units for oil pressure and temp, but all the wiring should be there.

Sometimes the oil pressure sending unit has two terminals and one is for the electric choke. It cuts power to the choke if the engine is not running.

I was wrong. The oil is mechanical on the 76 that I got. Not electrical. How would or can I hook that up to my system?

 

[AyWoSch Motors]

I was wrong. The oil is mechanical on the 76 that I got. Not electrical. How would or can I hook that up to my system?

If i remember correctly from my 75 gauges, the oil gauge had a little metal line running from the gauge to an oil port on the block. Thats easy to swap.

 

[imjohnny]

If i remember correctly from my 75 gauges, the oil gauge had a little metal line running from the gauge to an oil port on the block. Thats easy to swap.

Yeah, from what I am reading it is called a capillary tube. Trying to see where I can buy one right now. Would like to use these gauges. They are in great shape, and I have them here. I would guess the tube goes into the same spot that the sender goes in place of the electric sender, but not positive.

 

[AyWoSch Motors]

Yeah, from what I am reading it is called a capillary tube. Trying to see where I can buy one right now. Would like to use these gauges. They are in great shape, and I have them here. I would guess the tube goes into the same spot that the sender goes in place of the electric sender, but not positive.

2 have maybe 3 of those tubes. Gauge that fits it too.

 

[75gmck25]

The tube is a short piece of steel (I think) tubing that connects to the back of the gauge with a compression fitting. It makes the same connection to the fitting on the back of the block.

It’s been quite a while since I swapped clusters on my ‘75, so I am not sure of the details. However, what I remember is that I pushed the tubing through the grommet in the firewall, held the cluster up in front of the steering wheel and screwed the tube on the back of the gauge, and then pushed the cluster in place and pushed the tube through at the same time. Once in place you can screw the fitting onto the engine. It actually was not that hard.

 

[imjohnny]

2 have maybe 3 of those tubes. Gauge that fits it too.

I have the gauge but definitely want one of those tubes with the fitting to match up. Would you be willing to part with one?