Well recently my volmeter has been staying up around the max range (16 to 17). Then the other the day I noticed that the battery was making a boiling noise after taking a drive on the highway. Why would my system be overcharging? Is it a bad battery or is it in the alternator? Maybe a voltage regulator? This is happening on my 85 with the 22RE. Any thoughts?

Before coming to any conclusions, I would do some checking of a couple of areas... first make sure all connections from the alternator to the battery are clean and tight...

Then check your alternator output voltage with a known accuracy meter.. The stardard output range quoted per (at least one) Toyota manual was an alternator output voltage range of 13.9 - 15.1V with a fully charged battery (battery charging at 10A or less). This was measured at the "B" output terminal on the alternator..

If it's trully putting out 16 - 17volts, you do have an alternator regulation problem...

I have had a few weird batteries that would boil and spew acid vapor even with a good alternator..

My 88 22RE Pickup runs at 16-17 all them time..I wouldn't hold too much value to what the stock guage reads.

Test it with a voltage meter, my was off my about 1 volt or more.

but even then I have never had a single problem with mine so far,
Hope that helps <img border="0" alt="[Pirate]" title="" src="graemlins/bppirate.gif" />

EDIT:woops too late dandeman posted before I finished <img border="0" alt="[Hillbilly]" title="" src="graemlins/notooth.gif" />

<small>[ 31 July 2002, 04:40 PM: Message edited by: Hecubus ]</small>