Electrical Problems @ 17.5 VOLTS!? regulator woes?
 

I'm trying to install an electrical Autometer temp gauge in my truck. It was used but I wired it all up & no go - I thought it was bad. I sent it back to atometer & they replaced it n/c. I installed the new one & it moved a bit & stopped. I have it protected by a 3amp fuse but I tested the voltage & the meter read 17.58 volts when the engine was running! Whats going on here? has my voltage regulator gone south? Is the regulator that box on the inside core support? What should I be doing/looking for? I'd like to get this figured out before I have to pay Autometer to fix this gauge... Thanx for your advice!

:gmc: :canada:

That is a very high voltage reading. It should be around 14.5 volts at the battery. I would check three things to start with.

-Make sure the regulator on the radiator support is properly grounded

-Verify reading with another meter, just to make sure

-If reading is still high, adjust or replace regulator

An option is to replace the alternator with an internal regulator style alternator.

Jim

ttt

give the regulator a sharp rap on the side with a small hammer alot of times the contacts are stuck and doing this will free them up if it goes back to normal 12-14volts your set but if it happens again replace the reg

I had a regulator go out on a 67 Camaro. It was before dawn I turned on the headlights and headed down the road. All of a sudden the lights got brighter and brighter the faster I went, I could really see well. Then total darkness, burned out both headlights. Weird

:gmc:

ttt

ok - so I changed the voltage regulator & I'm getting 16.1 volts at the battery. Is that too much still? It droped like a volt & a half from 17.58! What is too much? Should I worry about it?

thats still too high it shouldnt be any higher than 14.5 your going to cook your electrical system along with a good change of having the battery boil and explode

so what is my next step?

It sounds like you do not have a decent multimeter & are relying upon dash gauges for accurate voltage readings when troubleshooting.

I would think that the first thing to do would be to go to most anywhere & buy a decent multimeter. Auto parts stores should have them. Radio Shack always has good ones for a somewhat fair price. They will also be able to help you pick a good one & give you a quick how-to.

John

But I am using a multimeter.....

16 volt is high, I have seen a charging system run that high for a short time with a very low battery. Put a full charge on the battery with a charger. Then test the volts with your tester at the battery with the truck running. If it is still 16v there is a problem.

I believe 14.5 should be measured at the alternator, and 13.8 should be measured at the battery while charging. The over charging can boil the acid out of the battery and cause serious corrosion in the engine compartment.

If your alt is still pushing 16V then your battery should be charged if not overcharged.
Whats the volts at the battery with the engine off?
If its under 12 then you probably have a dead cell in the battery.
This is an odd one.
The regulator should have corrected the problem.
I have also seen new regulators that were bad.
Do you know any one with a known good regulator you can try to rule out that possibility?

When my regulator went in my 71 it pegged my amp meter, by the time I got it in the driveway the battery was swollen and oozing out acid.
That was a close one :eek:

Denny

i'd try a different multi-meter,or at least compare the one you're using to a different one. some of the less expensive ones are not at all accurate

Put the meter across the Battery with the engine shutdown or you can put the meter on some other truck/car and see what it reads you could also go to A local autoparts store and They will have A multimeter they can put on your system to confirm the integrity of your meter. I had A bad meter that read approx 18V at my bat. It was A craftsman they replaced the meter. Instead of screwing around with the external regulator $. Buy A internally regulated alternator easy install and be done with it.

Gary

I'm thinking that i'll change to an internally regulated alternator soon, I just wanted to make sure I'm fixing the problem & not just stabbing blindly. I like MAD electrical's kit too. I THINK that since I just changed the regulator & I'm still putting out too many volts that my ground somewhere is bad. I'm going to check it tomorow. I'll kepp ya posted

it was a bad ground too. Now i'm at 14.3V. thanx to all for your help.