Last fall as I was using the dozer, seemed like the voltage regulator started acting up. Some days it would work fine, other times it wouldn't work for the entire day. Sometimes it would start charging for no apparent reason for a any length of time, only to stop for some unknown reason. So, I went down to cat, picked up a remaned alternator and slapped it in. Still not charging correctly. So I checked the voltage at the battery, (and cleaned the battery terminals.) its reading the same as the volt gauge, 12.9v. Next I went up to the alternator and checked the voltage there, 16v! Checked the voltage at the started and its at 12.9v, with or without the engine running. I did a visual inspection for obvious wiring issues and couldn't see any. I was wondering if anyone has any ideas or a wiring diagram for my dozer? vin# 5cj01041 Thanks guys, CJ
High resistance in wire from Alt to battery. Check any connections for corrosion. Later Bob
Yeap, thanks to Nige I was able to track down the different connections, and clean them all up. Honestly, the connections didn't even have corrosion, but just must have needed to be cleaned....or it started to randomly start working. It probably did, just to so it could come back to haunt me later. BTW, thanks Bob also for pointing me in the right direction.
I have a Dresser but it works the same way you discribe which seems to be normal for mine at least. A few things to keep in mind: A fully charged battery will read 12.9 to 13.2 volts depending on type and temperture just sitting there. So your 12.9 V sounds good. A battery under charge will read higher, around 14.5 V. The alternator puts out higher voltage and the regulator reduces it to the charging voltage so your battery and alternator won't be the same voltage. Unless you have electrical equipment running the only load on the battery is the fuel solenoid which is small. The way mine works is after I start up the dozer the battery get recharged and the needle is in the green charge section. After the battery reaches full charge the regulator shuts right off and the needle drops below the green charge section and sits on the 13 V line which is where it is if I just turn on the run switch w/o starting. It looks like it isn't charging because it isn't. It is full. Powering the fuel solenoid slowly wears the battery down a little and then all of a sudden the regulator switches on to charge the battery back up and the needle jumps to the green again. Then in a little while the regulator switches off again when the charge is full and the needle drops down again. At first I was worried watching that needle jump around and tryed to find something wrong but couldn't. I finally figured out that is just how it works. It always turned over strong. I think that is the key. If it turns over good all the time then your charging system is working OK. Anyway that is how mine works. EDIT: From what I was able to find out the very first electronic voltage regulators worked this way with the on/off characteristic. They turned off to prevent over charging. Newer electronic regulators maintain a steady charge voltage and just reduce the charge currant to prevent over charging.
I made an incorrect statemet above. The battery voltage and the alternator voltage should be the same as Bob said. It is just a wire between them.
check the back 2 poles of the amp meter in the dash for dirt dobber nest. dont ask how i know.