fixie guy

Dear all, I am new to forum and this is my first posting.

I installed a brand new VDO volt meter about a week ago in my Carerra 3.2 (89). Over the past few days, I noticed that the voltage reading (analog) on the Carerra 3.2 has gone up to as high as 16 volts. Actually an external volt ohm meter confirmed the reading at 18.73 volts when engine is idling. Is the alternator could be faulty and hence the over charging of the battery?

Just a bit of back ground on the recent tinkering which I did to the car that may or may not be attributing to the problem:-

1) yesterday, jump started a friends car twice, the first time with my engine running and the second time without.
2) installation of a brand new VDO volt meter
3) replaced the rear licence plate lighting which was damaged/cracked
4) replaced a blown out ceramic bullet fuse for the brake lights (5amps) with a 16 amps one as a temporary measure until my new fuse supplies arrive from an internet purchase
5) there is also another blown fuse which I have yet to replace and I cannot recall what electrical instrument/gadget it serves
6) I have also recently changed out the spark plugs in the car but I do not think it is related to the electrical problems
Can you advice what should be my next steps (trouble shoot or prescribed remedy)?

1986 Targa

Here you go............

And, do not drive the car, as this issue can cause other failures, such as your DME, and other electrical devices.

Most likely, your VR needs replacement.

pm me as needed.

Best,

Gerry

wwest

Where was it that you measured 18 volts...??

Assuming it was at or near the alternator, engine compartment, you probably have a poor front to back electrical connection. 18 volts at the battery posts would BOIL the electrolyte in very short order. If you measured 18 volts at the battery but did not encounter a sulpher odor then teh battery is open.

But in any case your should NEVER have the alternatormputting out more that ~15-16 volts.

New VDO is also suspect...?

VDO might be responding to voltage spiking, minor voltage spiking, which is normal.

dshepp806

You'd best get that 16 amp fuse OUT of the 5 amp position before you have FAR (fire) more concerns.

Your DME won't like the high voltages and could be damaged should conditions exist.

Tell us about your VDO install....

New alt/reg, probably...any idea as to how old the present alt/reg config is?

BEST!

Doyle

theiceman

wow where Ian when you need him

rusnak

Well it's a safe bet that he wasn't measuring from the back of the alternator.

I second what Gerry and Doyle already said. Wow, that's a lot of volts.

irobertson

I had similar symptoms, 18.5V measured at the battery and at the cig lighter.
I was boiling my battery dry, which was how I discovered it.
The case on my battery actually cracked from the pressure inside, and it was leaking acid.
The fix for me was to replace the Voltage Regulatior and clean up the battery area with a baking soda solution until nothing fizzed anymore.
I replaced my battery with an Optima so the=at if the VR ever went south again, I wouldn't have the same battery issue.

BTW, get that 16A fuse outa there.
You could light that wire up good with 3 times the rated amperage and then you would have some REAL trouble.

fixie guy

Thank you everyone for their advice..voltage regulator is currently being replaced. i am awaiting for my spare fuses to arrive!