Last year the alt stopped charging, If I gave it a couple good whacks it would it would kick in and charge at about 14v . I took it off to have checked out, was told the brushes where sticking , the guy did what every at no charge . again not long before same not charging started, at that I ordered a rebuilt alt, with new alt in place, its not charging at all !!! :-X Help Please :o
What model alternator was originally installed, and what model was it replaced with?
Have the regulator checked out, it could be bad. Are you sure the current alternator is wired the same way as the original? I believe there are some diagrams on this forum somewhere. Maybe a member can point you in the right direction.
A big reason that I like to have a local shop rebuild the old alternator. Did you do the replacement? Do you need a photo of the wiring? Check to make sure no wires were broken in the R&R.
Pierce
This alt, looks the same as the one I took off . it wasn't the original' it did however wired up the same . The output at the alt is 14 amp, the gauge however is wherever the Battery . As I'm driving the coach, I can see the voltage dropping at the gauge . I have a battery charger onboard, to keep the battery up, so I fire up the generator . that's about it . thanks guy for all help :o
14 amps or 14 VOLTS?
And, when you say voltage drops as you drive, how low does it get?
What is the voltage at the batteries when the voltage at the alt. is 14? Maybe you have a bad isolator.
Why don't you pull the alternator off and have it tested? This will save days of guessing. Re-built alternators, water pumps, etc have a poor reputation with assembly line work done by minimum wage workers with only basic training. Bead blasting with a little added paint does not mean it's a quality rebuild. Electrical shops have excellent reputations and will stand behind their work. The U300 alternator on the Detroit is in a very easy location for quick R&R.
Pierce
The replacement alternator needs to be modified for DUVAC system.
Firing her up today , for trip tomorrow, got it, amp not volt . Will check volt @ batt , today . thanks for all help guys ;)