Wiping out alternators
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Wiping out alternators
I have installed an electric cooling fan and new aluminum radiator in my jeep. After a few weeks I found that my fan would at times start to turn and then quit. Then I noticed at idle my alternator was only putting out 11.5 volts. And it seems when the alt is not putting out enough volts the fan tries to start and can't. Then the alt died. I replaced it with the stock 65 amp type and it quit within 2 weeks. Coincidence or is the fan putting to much load on it? I am running the fan with reverse polarity because it is mounted in front of the radiator. So the negative is carrying the current instead of the positive. Don't know if this fact or something I`might have done in the wiring is aggravating the situation. I have Hayden adjustable cooling switch with a 60 amp relay operating the fan. Also I checked with Autozone to see if I could get an 100+ amp alt but they did not show one on their books. Is there an aftermarket one? Any ideas out there?
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Joined: Jan 2001
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From: Virginia
I Have seen the belt squeal and lock up before the alternator blew up in most cases. You should have around 14.5 volts coming from the alternator. If it's a little low, I would check the belt tension, and you may need to up the idle speed a little bit. If the engine is getting warm and calling for the fan to come on, you may need to increase the idle speed anyway, to help cool the motor(water pump speed).
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Joined: Jan 2006
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alternators going bad
Thought I would add a little to this post.
You can get a larger alternator, go to a shop that does alternator and starter work. They have all kinds and sizes. Should Jeep not make a larger unit they can put on a larger Delco unit. Might not even take any special wiring, just hook it up.
They might be able to tell you what the problem is.
The fan might have a drag on the system being that it is hooked up reverse.
Good luck on this.
My $.02
You can get a larger alternator, go to a shop that does alternator and starter work. They have all kinds and sizes. Should Jeep not make a larger unit they can put on a larger Delco unit. Might not even take any special wiring, just hook it up.
They might be able to tell you what the problem is.
The fan might have a drag on the system being that it is hooked up reverse.
Good luck on this.
My $.02
