Alternator Meter Spike

[VTMopar]

Am I correct to assume that a sporadic spike while driving in my alternator guage probably indicates a faulty Voltage Regulator?   

Was driving down the road at about 50 today and all of a sudden I noticed a spike -- the needle went to charge as far as it could go and stayed there.   After several seconds, I let off the gas.... and then slipped it into neutral and the needle went back to normal.   A minute later - same thing.    Drove another 5 miles or so and nothing (just normal charge.)   Never noticed this happening before and it typically charges normally (and discharges normally -- like at stop signals).   So, this was quite a surprise.  Went I got home the battery had pushed fluid out through the caps..... which I flushed immediately.

Voltage regulator or do I have something else going on?   

VT Mopar
An

[dodj]

If you had to clean up the battery, your gauge wasn't lying to you. Definitely overcharging. Possible to be the VR. If it bounced a few times then back to normal I think I would be looking for a grounded field wire causing the alt to go full o/p. When the VR fails, it usually stays failed in my experience. 

[VTMopar]

Thanks for the tip dodj.    When I tried to find out more about grounded fields, I stumbled across a very good article (with diagrams) explaining the MOPAR charging system..... and how they changed in 1970 - and the use of another wire in converting to electronic ignition (which was done on my '70).   I haven't had time to do a thorough check, but a quick inspection of the wires off the Alt suggest a little tightening might be in order.  Hopefully, that solves it    thanks again!

VT Mopar

[mojavered]

My buddy had a bad voltage regulator and replaced it with a new part from autozone.  Went to a car show, lifted his hood and the battery had pretty much exploded.  Destroyed quite a bit of stuff under the hood.  He said he never once looked at the gauge.  Anyway, good catch on noticing the spikes.  Hope you find the problem.