DP Charging Problem
Motor Home 2001 Newmar / Freightliner DP After running for 20-30 minuter noticed charging dash meter not in normal position, after 45 minutes low battery light on. When I let off on throttle battery ...
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We had a very much the same problem with our 2001 Dutchstar, Freightliner, CAT engine. Cruising up hill, voltage drops to perhaps 12.4 volts, down hill voltage rises to perhaps 13.6 volts. Could not find anything wrong with batteries, wires or wire connections. Solved the problem this past spring by replacing the Leece Neville alternator with a new one from AJ-Electric via Amazon for about $260.00. Now voltage stays rock steady at about 14.1 volts.
I theorize that the difference between up hill versus down hill was due to vibration of the hard mounted alternator being driven by the engine power strokes when powering up the hill versus coasting down the hill. Perhaps one of the brushes was hanging up in its bore.
I purchased a replacement voltage regulator and brushes for the old alternator. Burnished the slip rings where the brushes ride and now it appears to work quite well on the test stand so it rides along as a spare in case ever needed.
Really heavy alternator to pull and replace solo, but I got it done. Getting the air intake plumbing in and out was a task also. (Be sure to cover the intake to turbo to be sure that nothing goes down the hole.) Needed to replace some of the air intake hose clamps as they did not want to loosen and also did the air cleaner while I was in there.
My installation does not use a diode isolator, it uses a BIRD and a Fat Boy relay to accomplish the function of the diode isolator without the voltage drop (0.6 volts) that the diodes would impose.
I theorize that the difference between up hill versus down hill was due to vibration of the hard mounted alternator being driven by the engine power strokes when powering up the hill versus coasting down the hill. Perhaps one of the brushes was hanging up in its bore.
I purchased a replacement voltage regulator and brushes for the old alternator. Burnished the slip rings where the brushes ride and now it appears to work quite well on the test stand so it rides along as a spare in case ever needed.
Really heavy alternator to pull and replace solo, but I got it done. Getting the air intake plumbing in and out was a task also. (Be sure to cover the intake to turbo to be sure that nothing goes down the hole.) Needed to replace some of the air intake hose clamps as they did not want to loosen and also did the air cleaner while I was in there.
My installation does not use a diode isolator, it uses a BIRD and a Fat Boy relay to accomplish the function of the diode isolator without the voltage drop (0.6 volts) that the diodes would impose.
