94' Cobra Dies with AC is on

Jul 2, 2019
46
8
18
38
TIFFIN, OHIO
I have already done that particular experiment in previous diagnostic attempts. I did a simple test the other night; started the car and target sprayed items in the engine compartment with a spray bottle. The car was running with the headlights and the max blower / max ac on. As i target sprayed the components with water i monitored the voltage at the battery. Nothing looked out of place and the car did not react negatively to the water application.

Dial it up to a little more extreme measures; full garden hose blasts. First targeting the alternator and its connections at the regulator. Then moving on to the AC clutch, the battery, the main power distribution center, CCRM, various wire loom areas, and finally ending on the distributor. The engine laughed at me and had no noticeable effects from the full blasts from the garden hose. I was actually impressed it did not shut down with direct full pressure hose blasts to the distributor.

I did notice one peculiar thing. The car when first started and while running cold with all the accessories on read 14.5 volts at the battery. As the car continues to warm up to normal operating temperature the volts drop down to 13.8 ish. I ran it for about 20 minutes monitoring this situation. I think if i left it run longer the volts would continue to degrade, but could not guarantee this scenario. Hit the alternator with the hose, cool it off and the volts rise back up to 14.5 volts. I can repeat this procedure and obtain the same results; cool / not hot alternator 14.5v, hot alternator volts degrade to 13.8 maybe less depending on temperature and run time.

My alternator gets hot. I did the spit test, like i do for brake rotors, and it sizzles off and vaporizes rather quickly. I do not have a temperature probe, but if i had to guess it is over 212° F (only by the rate at with the spit evaporates). Ideas on normal operating temps? I think my chinesian alternator might be under performing and or my system is drawing too much amperage.

I also noticed the main power connection at the power distribution box was getting warm, probably from pushing a lot of amps through. I think the headers are throwing a lot of heat towards the power distribution box which is not helping anything. More heat equals more resistance and effectively more heat build up / amp draw. Thinking about adding a temporary heat shield.
 
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Jul 2, 2019
46
8
18
38
TIFFIN, OHIO
No new updates....Everything runs great since blasting the engine components with the garden hose. Like usual nothing ever makes sense. Drove almost thirty miles yesterday after work. She ran great the entire time. Going to run this tank of gas lower than usual to see if their some correlation to fuel level and its creative way of malfunctioning.
 
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