Alternator works.... and then not

[Funrover]

I am running into a wall here. I have a Mean Green in my 92 RRC. At random times it will just quit. I am unable to duplicate any situation where it happens. I have checked all connections and all is tight and clean. Has anyone else had trouble with the Mean Green? I have had it for 5 or 6 years now but I still don't think that is the problem. I am going to take it off and have a shop test it for me but currently I am confused.

 

[BKCowGod]

if your luck is anything like mine, the shop will test it A-OK...

When it quits, how long does it quit for? How do you know it's out? battery light, noises? Does it quit more in the morning or the afternoon? Is it a gradual death or instant?

My factory alternator can just barely keep up with a nighttime load (lights, wipers, heater fan, radio) and when the EAS and ABS compressors both come on at the same time it gets angry, but my idiot light has never gone solid red on me.

 

[Funrover]

The tach dies and the battery light comes on. no noises. It quits at random times day, night etc. Loads don't seem to change anything either. It just does it when it wants to. Sometimes it will come right back on and other timers it takes awhile.

 

[BKCowGod]

Man, that sounds like a connection issue... The instantaneous nature of it - maybe it's an internal connection in the alternator that has broken partially?

The tach dies and the battery light comes on. no noises. It quits at random times day, night etc. Loads don't seem to change anything either. It just does it when it wants to. Sometimes it will come right back on and other timers it takes awhile.

 

[evilfij]

Check the tab on the alternator. I would carry a spare with me (I do anyway, but ....)

Ron

 

[1911]

I am running into a wall here. I have a Mean Green in my 92 RRC. At random times it will just quit. I am unable to duplicate any situation where it happens. I have checked all connections and all is tight and clean. Has anyone else had trouble with the Mean Green? I have had it for 5 or 6 years now but I still don't think that is the problem. I am going to take it off and have a shop test it for me but currently I am confused.

The Mean Green alt in my Land Cruiser has been flawless so far, but it's not as old as yours.

My first suspicion would be the ignition wire that excites the alternator; I would try replacing or at least jumping that wire no matter how good the existing one looks. Connector could be cracked or another intermittent open. But since the alternator works some times, ergo the unit itself is capable of producing current.

 

[Fivespddisco]

My first guess would be to look at the motor ground. You could run a new one from the bolt on the ALT to the neg of the bat

 

[11b4v]

Just replaced the Alt on my DII that was doing the same thing as yours until it fully died four days later. While trying to get the pulley off the old unit, I took it apart discovering that one of the brushes was worn out/sorta gone and was not making contact. Have a local alternator shop rebuild it. My local quoted me $100.

good luck.

 

[Funrover]

Check the tab on the alternator. I would carry a spare with me (I do anyway, but ....)

Ron

By tab you mean the plug in the alternator?

 

[Funrover]

I will look so more this weekend, It worked great today, even jump started a diesel Ford. I am going to swing by the local Napa and see if I can get a new plug in end.

 

[green]

I am betting on a loose belt. I had some of the same issues and found that the lower mount was loose, cause intermittent outages. It felt tight but after some digging I discovered the loose lower mount.

 

[Fivespddisco]

I am betting on a loose belt. I had some of the same issues and found that the lower mount was loose, cause intermittent outages. It felt tight but after some digging I discovered the loose lower mount.

It is common to run the belt the wrong way. It needs to come straight down after the Alt if my memory serves me.

 

[Ray Hyland]

I had a problem like this on my old mercedes. It would randomly die, mainly when it was warm. I knew it was electrical but couldn't find it. Checked every connection, every lead, all looked good. Turned out the coil lead was broken inside, and when the rubber around the lead was warm enough it would expand and break the connection. After sitting for a while cooling down enough for the rubber to contract, it would restart. It took FOREVER to track that one down.

Good luck.

 

[Funrover]

I will check the mounts and coil connections. I just wish I could track it down to a common occurance. Warm/cold etc etc doesn't make a difference. More to check tomorrow.

 

[achampagne]

Check the routing of the belt, what you describe is exactly what happens when its not routed correctly.