Help with a new cluster

[aGood'olBoy]

My only friend with a squarebody have a great relationship in which we always help each other with our trucks when they break down or just need some work. So we often trade parts as well. Today he gave me a mint cluster with a tach and all the gauges. The gauges appear to be in good condition as well. Buttttttt I'm not sure how to test these gauges to see which gauges if any need replaced. So can someone tell me how to test these gauges? Before anyone asks, I have a beaauutiful harbor freight multimeter. Any and all input is appreciated, thanks in advance!!!

 

[chengny]

If it were me, I'd have faith in 1980's GM. Just push ahead with the cluster changeover and assume that all the gauges in your new panel will function properly.

If you crank up the engine for the first time after exchanging the clusters and find that a gauge (or gauges) doesn't work - just replace it with one from your current cluster.

Another option is to test the new gauges by plugging them into your current cluster - which will need to be released from the dash (and easily opened) at some point early in the exchange process.

 

[bucket]

If the printed circuit looks good, go ahead and try installing it. The small gauges can be replaced with the cluster in place. Expect the tach not to work, maybe you will be lucky though.

 

[aGood'olBoy]

I assumed most of the gauges were in good shape as gauges don't typically go bad. But the only reason i wanted to test it is i'm going to a different type of cluster. I currently have the 85 mph speedo, big fuel gauge, and dummy gauge. The new cluster has the tach 100 mph speedo and the rest of the gauges.

 

[aGood'olBoy]

Will i need a harness for the new tach? i have a crappy Sunpro tach that doesn't work. i'm not sure if I could modify the sunpro harness to fit the stock tach

 

[bucket]

Will i need a harness for the new tach? i have a crappy Sunpro tach that doesn't work. i'm not sure if I could modify the sunpro harness to fit the stock tach

If the new cluster is '78 and later (electric oil pressure, not mechanical) it will plug right in place of your original cluster. You can reuse your current tach wires for the factory tach, it just has ign/ground/tach signal. If your truck has cruise, it probably has the VSS mounted to the back of the speedo. You can swap it over or just do without it if you don't care about cruise.

 

[aGood'olBoy]

The only gauges that work on my cluster currently are the speedo, fuel gauge kind of, and volts. I have one of those autozone specials, oil, volt , and water temp gauge clusters and only the oil pressure works on that haha. My oil pressure line is a clear tube with oil in it so I'm assssuming its a mechanical gauge?

 

[bucket]

Your factory '85 cluster uses an electric gauge. Your aftermarket gauge likely gets it's reading from the port near the distributor, meaning somebody likely removed the original oil pressure sending unit. If so, that will need re-installed and plugged in if you want the factory oil pressure gauge to work.

 

[aGood'olBoy]

Makes sense. That should be a cheap date then. Should.. I'll try to dick around with that tomorrow see if I can get some of the gauges working