some zilch

ok, a bit different then usual, but im sure you guys can help me out
-my truck is a 1997 ford f-super duty; the early version of the f450. i installed a 24v out of a 2000 dodge 2500 3 years ago, and it has been flawless since.

i have developed an issue in that the ford gauge in the cluster and a stand alone type volt meter show a very steady voltage surge while the engine is running. a meter shows it to be 12.9-14.4v over and over again at a very steady rate. it is enough to make the engine surge its RPM as well. when this issue first started, it would only do it at idle (but steady out at driving RPM), now it does it at all engine RPM.

This truck does not use the dodge pcm, but uses the stand alone chrysler voltage regulator that everyone switches over to when their pcm stops charging the battery. it had functioned well for 3 years until now.

i first replaced the regulator with an AC Delco unit, and the plug that plug into it; made no difference. i then replaced the alternator; has made no difference. when i pull out the "alternator" fuse, it stops charging and the needles are steady.

this truck is set up to function as simply as a 24v can function, and functioned well for me until now. could a bad battery (truck has 2 grp 31s hanging off the frame rail behind the pass side of the cab) cause this issue? i have literally replaced everything else in the charging system

gorms

Try disconnecting one battery at a time while running. I'm almost positive it will go steady once they are disconnected.

ecmexchange

Are you still having the problem? I was wondering if gorms suggestion worked.