The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Removing the Instrument Cluster on a 1966 C10

Could someone help a newbie here? I'm am trying to get my gas gauge to work on my C10. It always reads full once the ignition is on.
Steps: I have done so far:
1) Replaced the sending unit
2) Checked the new sending unit and it is producing about 10 - 12 ohms. The tank is less that half full so seems reasonable
3) Replaced the sending unit wire and check it at the end and it again is showing 12 or so ohms on the end where it goes into the fuse block
4) Check the fuse where the sending unit wire is plugged into and it is ok (not blowned)

I feel it must be behind the instrument cluster where the issue is. I see there are 5 screws on the instrument cluster holding it on to the dash. All the videos on the internet doesn't show you how to remove it just shows how to test the gas gauge once it is out.

What are the steps to remove the instrument cluster on a 1966 Chevy C10? Like I said I'm a newbie, so please be fairly detailed please.

Welcome Brian.
You did not mention the ground when you wired and replaced sending unit. I suspect you did get a ground but just did not mention. But if not, please confirm. Dash removal is a bigger job and should only be tackled once we confirm all troubleshooting otherwise.
The dash bezel is fastened 🔚 with those screws you see. Beyond that you pry and wiggle and will quickly find use for foul language. Good news is the steering wheel will be in the way. Give us a chance to see if we can work this without removing dash.

Hambone is correct on all accounts.

Make sure sending unit has a good ground. If your gauge is reading the gauge is working as it takes information from the sender.

It sucks to get the cluster out of there.

I did check the ground and it is good. I removed the 3 hex screws on the back of the gas gauge and the gauge and the oil gauge come out. I was able to remove the gauge and one of the wires is not attached to the back of the gauge. Surprised that wires are not covered. I will have to solder it and see if the gauge will work then.

If I check the ohms on my multimeter what should the reading be if it is working.

It's so much fun I've done it 3 times now this year alone, the Ammeter that I went through so much trouble to make work properly (I like and prefer a stock looking dash, however I was greedy and wanted it all to function as intended) it repayed me by finding the least path at a loom leaving the passenger side bulkhead. When it was finally done smoking it pretty much consumed all wires from the regulator into the cab and back out except the fuse block, dimmer, light switch to harness and blower motor wiring. Everything else was one wire. So I'm getting ready to wrap and hang the new harnesses I built......"Painful wiring" is my outfits name!!
I drop the column down an inch and she wiggles right out, but mines so used to it now we're old hat

I'd give you a number, but I'm not sure if I can trust it yet, I have to verify that mine still functions properly prior to that. I don't want to lead you astray. If nobody else answers you I should get back to you in about 2 hours

How to test the gas gauge has been discussed hundreds of times on Stovebolt. Please try the Stovebolt Search (little praying boy) in the left margin of every page. The numbers and procedures will be readily available there.

Go easy on him. He’s new to the Stovebolt and hasn’t learned what info can be found and where to find it.
It took most of us at least several posts to learn our way around.

Brian Willis,
Crazy question, but I’ve seen this happen before. Is the insulation washer present on the sending unit and is it in the proper position

I don't have a insulation washer...

Be sure to unhook the battery first.

My experience on my '65 c10 with factory gauges:

Getting the cluster loose is fairly easy, there are a few phillips screws around the side, but the ignition switch, cigarette lighter and headlight switch need to be removed as they go through the metal dash and the cluster both.

The ignition switch comes out by taking the round bezel off, which do some thinking about tackling that before you use pliers on it.

The cig lighter, you unplug it in the back, then it unscrews into two pieces, then one part comes out the front.

The headlight switch is a little funky. First up, feel around the headlight switch and you will find a button on the side of the switch box, under the dash. You can look up the part on the various vendor sites to get a visual. You pull the knob all the way out, keep your hand on the knob, depress the button on the side of the box and hold it, and the knob will release and the rod will come out(you can kinda feel it get loose). Then you take the bezel loose and the headlight switch will drop down. Once the cluster is back in, to reinstall, put headlight switch in place, run the bezel down, get the knob/rod into position. Depress and hold that button down and wiggle the rod/knob back into place and release the button. If it's done right you will feel it working the switch from on to park to off.

Also the bezel for the manual choke screws in/out if you have a manual choke still, I don't know if you will have enough wiggle room or not... and the wiper switch knob has a tiny little flat blade screw on it to take it loose(you just turn it a bit and it comes off, you don't have to take it out of the knob) and if I recall it also has a little bezel thing that needs to be unscrewed.

Mark the wires for where they go in the back of the instrument cluster, most of them are wires for the little bulbs for the dash lights, illumination at night, high beam indicator, blinkers, etc.

Most of the plugged looking wires are pretty obvious, the gauges and things, but mark them too just in case, also take some photos if you can, that will help!

The only tricky one is the oil pressure line to the back, if yours is still hooked up, just be firm but gentle... and remember to hook it back up before you crank the truck. I learned that one the hard way. hah.

Once everything is unplugged and loose, it is a bit of a dance getting it out, as it will whack into the steering column. I pondered once about loosening the steering column bolts to drop it a bit, but I haven't tried that yet. Maybe it is just one of those 'hold your tongue just right' things and do a dance to get it out, but for me getting it in and out of the dash opening was always the aggravating part.

If you have nice paint on your steering column put some tape on it or a shop rag, thin towel... thing cardboard, something to protect it as the cluster will sit right on top of it during part of the in/out operation.

To reinstall, I usually do the oil pressure gauge first. Then I start sort of from the center like, plugging things back up.

If you have a few bulbs wrong, just wait until it gets dusk sometime or dark, then fiddle around with them until you get them in the right place.

Good luck,

-Woog

That’s the problem then. The insulation washer is absolutely necessary.

That might be an issue with the insulation washer, Lugnutz, where do I get one of those? I also changed the actual gauge got it from Classic Parts. It was half full when I got it installed. When I went to the gas station and put 11 gallons in it it now reads Full. I filled it up so I think I have resolved the issue. Thanks for all your help.

Thanks to Woog. He answered my original question. I'm glad I didn't have to do all that to get the gas gauge out and remove it. Just 3 1/4 inch hex screws to get the gas gauge cluster and oil presser cluster out together and then replaced the gas gauge and it is working, I think. Ha Ha

Thanks again for helping me resolve the gas gauge issue...

The wire connection at the sender (where I show the insulation washer) must only make contact with the stud and nut. The insulation washer prevents contact with any other metal. A friend of mine observed drastic changes in his fuel gauge needle when making slow turns left and right. New sender didn’t solve the problem. His insulation washer was not installed in the proper location. The round mounting plate should have a ground wire that grounds the unit to the back wall of the cab. If the gauge wire has contact with the area that is grounded, then the gauge will not work properly. You could make a small washer from a yoghurt lid and it would work the same.

My melt down took all my gauges with it, sorry