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Charlie Hood
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Altenator Problems

Post by Charlie Hood »

My idiot light for the alternator had been coming on so purchased an adjustable regulator from IAP, and installed. I checked and it was putting out 14.25 Volts. 1) Is that too much?
However that did not seem to solve the idiot light coming on. Also I notice that idiot light seems to get brighter as the RPM's increase.
I suspect that a diode is bad?
What is the latest on the alternator?
2) What is a good/easy replacement?
3) What Amps?
4) Source for parts
5) Help :roll:
PS I did tighten the fan belt.
Last edited by Charlie Hood on Mon Jan 10, 2005 7:21 am, edited 1 time in total.
mcandiago
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Post by mcandiago »

Hi Charlie,

No, 14.25 is not to much.

A brighter idiot light would indicate that the output of the from the alternator is actually droping with increased rpm, which is usually the opposite effect of what you'd expect from a dodgy alternator.

You can easily check this by using, preferably a DMM connected to the battery terminals and then revving the engine. If the output drops compared to idle, the problem is most likely with the alternator itself.

I was having similar problem with my warning light. The problem was that the lead from the alternator to battery via a junction connector had over time developed a slight resistance in the cable (Less than 0.3 Ohms, but because the charging current is fairly high, this led to a significant voltage drop at the battery)

So...

1. Measure the voltage right at the battery terminals if it is not greater than about 14V, connect a lead directly from the alternator output directly to the battery + post and see if that increases the voltage at the battery terminal.

2. I also found that the the terminal junctions, can over time, get coroded and should be cleaned periodically. Cleaning both terminal junctions on both the left and right side of the car eliminated my battery warning light problem.

Hope this helps

Marco
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Charlie Hood
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Post by Charlie Hood »

Up date on what I've learned about the Delco CS 110

http://www.alternatorparts.com/

http://bernardembden.com/xjs/altmove/
http://www.alternatorparts.com/cs130_sbpage2.htm
There is some good stuff here even if you are not changing.
chood
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Charlie Hood
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Post by Charlie Hood »

The problem is pretty much solved... for now anyway. I added the voltage regulator and that helped some. Going on what Marco said, but taking it a bit further. Being a devout follower of the church of Greg Gordon, my connections were clean, however the crimped ends were the problem. I gave them a couple shots of contact cleaner, and then gave them a good squeeze with my biggest crimpers. I’m thinking some solder may be in order.
I guess it goes back to “the it worked when it was new…”
I still want to put in a different unit, but this will keep it going until I find what I want.
I’m still open for suggestions?
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