Hey there I am new to this forum and I had a question about my 1966 alternator charging system.
I recently purchased the vehicle and none of the gauges are working. I don’t think the alternator is charging. Any suggestions on where to start troubleshooting? Thanks in advance.

 

None of the gauges are working? Are you including the speedo, tach, water temp, and oil pressure in that? Since these are not all driven by the same system (tach and speedo are driven by separate cables and oil pressure is driven by an oil tube), if they are really all inoperative you have several issues to address.

But let's start with the charging system. It's easy to do a basic check. Put a voltmeter across the battery with the car off. Should read around 12.5-12.8 volts. Start the car and rev it to about 2000 rpm--with the car at 2000 rpm (doesn't need to be exact, just not at idle), the voltage across the battery should now be around 13.7-14.5 volts. If so, your charging system is fine. If it still reads 12.5-12.8, your charging system isn't charging.

Welcome to the forum and welcome to the club of C2 owners. Post a photo or two of your car. We all love to see members' rides!

 

Hey thank you for the reply.
Correct, none of the gauges are working including the speedo, tach, water temp and oil pressure.The charging system definitely is not charging. It has a relatively new battery and tested the battery reads at 80%. Do you know if there is a fusible link that feeds the fuse box? if so where would it be?

 

It would help if you could post apic of your gauges. If none of them work, you probably don't have original gauges. The tach, speedometer and oil gauges from the factory are mechanical, and all 3 failing at once is less likely than an asteroid strike. To answer your question, there are no fusible links in the alternator circuit. You'll need to get your hands on a clip on or other ammeter to check whether it's charging if the dash gauge isn't working.

 

Welcome to the CF. We are always happy to provide assistance with problems. Do you have any experience doing basic car work? You should have a Chassis Service Manual, can be purchased on line. Also, go on YouTube and search for basic testing for your problem. Your issue may well involve removing the gauge cluster to determine the mechanical (tach, speedo, OP gauge) issues you describe. There are on-line guidance for that task. Dennis

 

I wrote an article on description and testing of the charging system.
Send me a PM with your email address and I will send you a copy.
The speedo, tach and oil pressure are mechanical and has nothing to do with the electrical system. That is weird, maybe someone had the cluster out and never connected anything. Do you have dash lights and signal indicator lights?

 

The fact the battery is at a relatively low charge does not necessarily mean the charging system isn't working. It depend on when the car was last driven, if there are any parasitic draws, and the general health of the battery. I recommend you do the test I outlined to establish the starting point for analysis.

To the best of my knowledge, pre-1967 cars did not have fusible links. However, I'm always leery of relying on what was stock, as these 50+ year old cars often have had many modifications done to them. Knowing what GM used originally is helpful, but that's just a starting point. Eventually you will need to figure out what your car has.

We'll have to address the speedo, tach, and oil pressure gauges separately as they are all mechanical. Let's start with the charging system. Coincidentally, that's the first issue I had to resolve on my '64 when I first got it, so I know what you are going through.

 

Work on Post #2 then we can start guessing......I say guessing because I'm weak but dangerous when it comes to electrical issues. Alternator, Regulator, Harness????? I am not fawned of Replacement Regulators. I had a 65 Coupe with Charging issues. Fixed it, but it was a process...

Welcome!!!! Stick with the Forum Members. These guys are quite good!!!

Good Luck!
Dcamick

 

Sounds like the dash is simply bolted in place, but not hooked up. That is about the only reason for the described symptoms.

 

If your post is for real, you'll get plenty of help. I suggest you fill out your profile with car info and general location, like what state you live in.

Only one gauge depends on the charging system working. The battery gauge will read whether the battery is charging or discharging and it works with or without key on.
The oil pressure gauge, tach and speedometer don't care if you have voltage or not. Or charging or not. None will work with engine off and car parked, but they are mechanical only gauges. If the oil pressure gauge doesn't read, I suggest you not start the car. If the oil line is not connected to the back of the gauge, you'll know because oil will run out on the floor under the gauge.
The fuel and temp gauge will read anytime the key is on, but will not move if the fuel is empty AND the engine is cold. They only read what the current fuel and temperature are.
It is almost impossible to have a car that starts with all gauges not working. Did you buy the car recently and it has not been run?. Does it run now? Do you know any reason the instrument cluster would have been removed?
You've already been told how to check to see if the car is charging by measuring the voltage at the battery with engine off and engine on. I don't think that's possible unless you have multiple instrumentation issues, the most worrisome being the oil pressure gauge.

You have no profile information showing in your forum profile, and only these two posts showing. So if you are for real and not just playing around with the forum continue posting with what you have going on after trying some of these things. There are LOTS of people here willing to help, don't abuse them if you're making this up, and welcome to the forum and expect as much help as you need if you are sincere.

 

If the problem is genuine, we are assuming a lot. The only intelligent way forward is to see pics of the dash and engine compartment -- otherwise we're just commenting on what should or should not be there as we know these cars.

 

That’s assuming that a brand new user knows how to post pictures.