Volt Gage Reading Pegging at 16 volts?

First, this isn't a Z-car but a relative of sorts, it's a 1978 200SX

From what I can tell besides being very ugly it's the "Dog of the Datsun World". I can't find much information on it at all via Google or even eBay. I bought the car for $500.00 and it runs really good except that the Voltage Gauge goes from 4 to 16 and and when I start the car up it up it pegs at 16

Here's a picture taken when the engine is not running so you can see the gauge...



I have a brand new Battery in the car that is fully charged. Everything else seems to work just fine.

Can anyone provide some insight as to where I should start looking for the problem.


Apologies ahead of time for posting this on a Z-Forum but I can't find an active forum for this car and I figured someone on here might have some knowledge or experience with this kind of issue.

Here's some pics...



Thanks ahead of time...

 

Save time and take it to an auto parts store that will check the charging system for you. Then go buy a Zcar cause-damn!

 

Took it to Autozone and at the time it had a bad battery in it, (I didn't know it was bad as it always seem to work fine but their testing machine said the battery was bad.

I put in my brand new batter out of my 1975 Jimmy and the gauge reads the same. Going to take it to a mechanic this morning and see if they can diagnose the problem.

Probably simple like replace the alternator or voltage regulator, but wanted to pick everyone's brains anyway.

Thanks!

 

Hopefully the mechanic doesn't charge much for telling you something you could find out for free.

It's the alternator / voltage regulator..............

 

Nah, he's a good car buddy with all kinds of testing equipment. Plan on replacing all that stuff, just hope it's nothing more complicated. The car sat in the desert for un-driven for at least the last 2 years, hoping a field mouse hasn't chewed through some wires or something like that.

 

Charging system could be in great shape...

It pegs at 16v when the car is off, and the ignition switch is in the run position??

If so, then the gauge is crap. It happens. I am not sure I would trust much of the gauges without confirming it with a simple volt meter... If you actually have 16v's then you have a super batter, or a regulator problem with your alternator. Or loose connections to the sensing wire to the regulator.

Good luck.

Man.. I have not even seen one of those old dogs. That has to be the ugliest car I have ever seen next to some Saabs. That's awesome!

 

You're right, it is UGLY

I got a new alternator and and a new alternator belt and will put it on in the morning and see what happens. I couldn't get it over to the mechanic today so went a head an decided to replace everything new.

The temp gauge goes to half way shortly after it's warmed up so I'm guessing the next thing will be to have the radiator cleaned or replaced.

It was an air conditioned car and everything is there but it's not blowing cold, my guess is that since this was an R12 system that it's probably going to need everything rebuilt to work again and not worth the money.

Anyone have any experience with this era air conditioning system?

 

Had a real nice one, look at my posting history...

https://www.zdriver.com/forums/searc...earchid=193371








Sold it and got this as I'm kind of a Chevy/Convertible/Truck guy...











Since the price of gas is going up and up we bought the Datsun 200SX to drive back and forth to work and just keep the Jimmy for a toy.

I drive the I-15 from Apple Vally to Irvine about 5 times a month and don't want an new car just for commuting as I don't want the payment and traffic is crazy. My Z was hit once on my commute and it about killed me as it was all original and had never been hit.

If this 200SX gets hit it won't bother me at all since I only paid $500.00 for it, as long as I survive.

I usually drive in the early morning and late at night so that kind of reduces my chance as I'm not in the heaviest traffic most of the time.

Almost bought another 260Z as I found one in this guys backyard in quasi-running condition and it's a beater, but went with the 200SX as at least the body is straight and new they were supposed to get around 30 miles per gallon.