Alternator not charging
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Alternator not charging
It's a 91 460 in an RV, I Took the alt to an auto elec shop and had it checked, was told it is perfect
There is a box under the hood that sorta looks like a VR from the 60's or 70's. But this one has a big plug with about 5 or 6 wires on it.
I always the that alternators had the VR built into them?
There is a box under the hood that sorta looks like a VR from the 60's or 70's. But this one has a big plug with about 5 or 6 wires on it.
I always the that alternators had the VR built into them?
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From: Denver Metro Area, CO
Built-in regulators didn't come about until the mid-80s with the 2G alternators, they were always external before that.
RVs & heavier-duty trucks were always lagging behind in technology, and trucks as a whole lagged behind cars.
RVs & heavier-duty trucks were always lagging behind in technology, and trucks as a whole lagged behind cars.
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How many batteries ?
Might have more than 1 battery, and might have an isolator. (splitter). Those things will have markings like "A", "B" and "ALT" and usually have cooling fins on the top. In my opinion a horrible thing to have. They do very little good except on an ambulance, and cause a boat load of problems by being unreliable and causing alternator stress.
If you can find this thing on the firewall somewhere, put all three wires together as a test. If alt starts charging the isolator is the problem
If you can find this thing on the firewall somewhere, put all three wires together as a test. If alt starts charging the isolator is the problem
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it has three batteries, I think the alt is a 100 amp alt
one battery is just for running and starting the RV, but I think the alt may charge all three.
I have an emergency start switch that in the event the chassis battery will not start the rv I can use the house batteries which are 2ea 12 v batts hooked in parellel to start the rv
If I pull one ground wire off the chassis batt when motor is running the motor stops
Wire diagrams are nice but hard for me to understand unless they are in color and are made very clear. Most diagrams I see are confusing as heck.
one battery is just for running and starting the RV, but I think the alt may charge all three.
I have an emergency start switch that in the event the chassis battery will not start the rv I can use the house batteries which are 2ea 12 v batts hooked in parellel to start the rv
If I pull one ground wire off the chassis batt when motor is running the motor stops
Wire diagrams are nice but hard for me to understand unless they are in color and are made very clear. Most diagrams I see are confusing as heck.
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Fleet Owner
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From: Easton,Ks
Sounds like your parallel relay is stuck closed and the engine battery has lost its ground.
Or you are starting it with the emergency start switch. When the engine starts the emergency start relay will come in auto to charge the chassis battery and this will keep the engine running. Then when you take the ground away from the chassis battery the alternator will lose its charge power from the wire from the cluster. With no power to the Ignition now the engine will die.
Bottom line is that the engine battery has an open cell or the ground cable from the engine battery to ground is open.
Or you are starting it with the emergency start switch. When the engine starts the emergency start relay will come in auto to charge the chassis battery and this will keep the engine running. Then when you take the ground away from the chassis battery the alternator will lose its charge power from the wire from the cluster. With no power to the Ignition now the engine will die.
Bottom line is that the engine battery has an open cell or the ground cable from the engine battery to ground is open.
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Sounds like your parallel relay is stuck closed and the engine battery has lost its ground.
Or you are starting it with the emergency start switch. When the engine starts the emergency start relay will come in auto to charge the chassis battery and this will keep the engine running. Then when you take the ground away from the chassis battery the alternator will lose its charge power from the wire from the cluster. With no power to the Ignition now the engine will die.
Bottom line is that the engine battery has an open cell or the ground cable from the engine battery to ground is open.
Or you are starting it with the emergency start switch. When the engine starts the emergency start relay will come in auto to charge the chassis battery and this will keep the engine running. Then when you take the ground away from the chassis battery the alternator will lose its charge power from the wire from the cluster. With no power to the Ignition now the engine will die.
Bottom line is that the engine battery has an open cell or the ground cable from the engine battery to ground is open.
The chassis battery and the house batteries are all brand new
The chassis battery ground and positive wires are also new
The starter solonoid is also new and the starter was just rebuilt.
Fleet Owner
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From: Easton,Ks
You say it will die when you take the house battery ground cable off so that means the Ignition, computer or fuel system is not getting power to them from the engine battery.
The only way if wired right that they can get power from the house battery is through the parallel charge relay.
The only way if wired right that they can get power from the house battery is through the parallel charge relay.
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You say it will die when you take the house battery ground cable off so that means the Ignition, computer or fuel system is not getting power to them from the engine battery.
The only way if wired right that they can get power from the house battery is through the parallel charge relay.
The only way if wired right that they can get power from the house battery is through the parallel charge relay.
I pulled the alternator and had it checked along with the starter, the shop said the starter was on it's last legs but the alternator was perfect. and now here I am looking for help for a place to check
Fleet Owner
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From: Easton,Ks
You have a 1991 Ford with a carb on it???
The last time that Ford put a carb on a 460 was 1987 or 1988.
An alternator will not charge with a dead (open) battery. It needs power to charge, it is not like the old generators.
If I were to guess I would say you are not getting power from the dash cluster to the alternator. If not that the "A" wire is not getting power from a battery.
The last time that Ford put a carb on a 460 was 1987 or 1988.
An alternator will not charge with a dead (open) battery. It needs power to charge, it is not like the old generators.
If I were to guess I would say you are not getting power from the dash cluster to the alternator. If not that the "A" wire is not getting power from a battery.
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I removed the voltage regulator to get the plug off and when I saw the back all the contacts were very rusted, when I got the plug off one of the contact prongs came off with it. So I went to the closest auto parts store with the regulator in hand and got one that looks just like it for an F-350
After I installed it I started the motor and it started to show a charge but it went to almost 16 Volts on the gauge, I double checked that with a voltmeter across the battery poles and yup almost 16 volts there too.
Could the new regulator be defective?? or could something else cause that?
I read somewhere that the max volts a 100 amp alternator puts out is around 16 volts
After I installed it I started the motor and it started to show a charge but it went to almost 16 Volts on the gauge, I double checked that with a voltmeter across the battery poles and yup almost 16 volts there too.
Could the new regulator be defective?? or could something else cause that?
I read somewhere that the max volts a 100 amp alternator puts out is around 16 volts
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Voltage Regulator Sense Terminal
If the V. reg. senses low voltage from a bad connection where the harness plugs in to the alternator, it "thinks" the battery is low and over charges. Same thing for a bad ground (lots of corrosion on aluminum frames on alternator) I don't know what year you have, but from the category it probably says "A" on the voltage reg. Go to a junk yard and get a nice looking plug. If it plugs in it will work. Most Fords in the 90's have that plug. Some part stores may offer that plug. It's called a repair harness.