hey everyone, new guy to the forum here. I run a home of sorts for abused and forgotten 4x4s got an 84 k5 a few days ago and have been trying to figure out the charging system problems. i got it to start charging finally. but now when it has been running for a few minutes and you shut if off the battery sounds like its boiling. ive heard some do this when they are under heavy charge setting on a batt charger, but never in a vehicle. any ideas on this phantom?