Dummy Light Cover Source? Switch to gauges?

[blindbug]

To make a long story short, my dummy light cover on my 86' C10 Custom Deluxe 3 Speed Automatic is shot. I've looked at a few places but don't seem to see anyone selling the dummy light covers separately. Does anyone have a source for this little red piece of plastic?

This brings me into my next thought: change the whole cluster out. The gas gauge and speedometer / odometer work, and when I turn on the truck, at minimum the light behind the battery indicator lights up. If I keep the current cluster, I want to buy a new printed circuit, at minimum, to get all my lights working correctly (it's a bit corroded). But at the price of a new circuit, I can almost afford to swap out the cluster for one that has actual gauges for temp / oil / battery voltage. Should I bite the bullet and swap out the cluster? How much of a hassle is it to switch from a dummy cluster to a gauges cluster? Aside from the sending units, it there much more that is necessary? If my truck didn't come with sending units (just dummy sending units), do I just pull the dummy unit out and put in the gauges unit? I wish I was more knowledgeable on the subject. I have the know-how, if I have a how-to, but just not familiar enough with the process of switching out a cluster. I don't want to get into a cluster **** of a problem (see what I did there? )

[ray_mcavoy]

I don't think anyone is reproducing those red plastic lens/covers for the warning lights. So looking for a good used one is probably going to be the only option there.

If you decide to swap over to a factory gauge cluster, that will involve "re-pinning" the gauge cluster connector in addition to swapping out the sending units. Both the warning light and gauge clusters use the same size/type connector but the electrical pin-out is different between the two. The process of "re-pinning" the connector basically involves identifying and labeling all of the wires going to the connector, carefully extracting the terminals from the plastic connector shell, and re-inserting them in the appropriate cavities to match the new gauge cluster. If you do some searching on this site, it should turn up some pin-out charts for the various 73-87 clusters.

Although you could use most any 73-87 gauge cluster, it will be easiest to swap in a 78-87 gauge cluster. Those years will have a voltmeter (so you don't have to hook up any special wiring for an ammeter) and they have an electric oil pressure gauge (so you can simply re-purpose the oil light wire for the sender instead of having to run an oil line for a mechanical gauge). Note, the 88-89 R/V series gauge clusters are suitable swap candidates as well.

[blindbug]

Originally Posted by ray_mcavoy

I don't think anyone is reproducing those red plastic lens/covers for the warning lights. So looking for a good used one is probably going to be the only option there.

If you decide to swap over to a factory gauge cluster, that will involve "re-pinning" the gauge cluster connector in addition to swapping out the sending units. Both the warning light and gauge clusters use the same size/type connector but the electrical pin-out is different between the two. The process of "re-pinning" the connector basically involves identifying and labeling all of the wires going to the connector, carefully extracting the terminals from the plastic connector shell, and re-inserting them in the appropriate cavities to match the new gauge cluster. If you do some searching on this site, it should turn up some pin-out charts for the various 73-87 clusters.

Although you could use most any 73-87 gauge cluster, it will be easiest to swap in a 78-87 gauge cluster. Those years will have a voltmeter (so you don't have to hook up any special wiring for an ammeter) and they have an electric oil pressure gauge (so you can simply re-purpose the oil light wire for the sender instead of having to run an oil line for a mechanical gauge). Note, the 88-89 R/V series gauge clusters are suitable swap candidates as well.

Great information, thanks. I spent years doing car audio, so the electrical isn't a big issue for me. In fact, in my day car (a nissan :/) I made a custom adapter so that I could pigtail off the factory head unit and get RCA out to an amp... basically I've done the re-pinning of electrical connectors, is all I'm saying. Reading the pin-outs is what allowed me to figure out if some of my cluster lights were working or if they were toast...

That being said, a clear instruction on how to swap would be 'instrumental' in getting me rolling! I know that doesn't exist, well most likely doesn't anyway.

[ray_mcavoy]

You're welcome!

Since you're already familiar with re-pinning automotive electrical connectors that should make the swap a lot easier. The warning light & gauge clusters are the same size/shape and have all of the same mounting points so the physical installation portion of the swap is fairly straightforward.

One thing you will have to address is the lack of a "battery" or "gen" light in the gauge cluster. The OE wiring in trucks with factory gauges included a special 10Ω resistance wire (to take the place of that light bulb) in the alternator's exciter circuit. A 10Ω, 10 Watt resistor can be used as a suitable substitute. Or you can go a bit higher on the resistance and not need as high of a wattage rating. I believe the SI series alternators will still operate correctly with around 100Ω or so in that circuit. And if you ever plan on swapping to a newer CS series alternator, those require a minimum of 35Ω.

Another thing to consider is the vehicle speed sensor (if your truck has cruise control). The 70's & early 80's speedometers didn't have these sensors and there were at least a couple different buffer circuits used (identified by yellow or green plastic case). But if you get a mid 80's gauge cluster (from around the same year as your truck), you could always swap your existing speedometer assembly over into the gauge cluster. And you might even want to do that anyway just so you don't end up with a different odometer reading.