[driver]

I did the test with a test light between the neg-cable and neg-battery post with the neg- cable off but my question is i have a kill switch on my car which the test light comes on with the kill switch on but remains out with the kill switch off. Should I have the kill switch on or off when doing this test? Thanks,Bill

 

[rocks66ss]

Think about it. what does the kill switch do? It completely breaks the electrical circuit.........so you wont be able to test if your switch in in the off position. there is no electrical circuit to test. So you need it in the on position. The purpose of the light test is to find what circuit is causing a drain on your electrical system.



Rocky

 

[driver]

Thats what I thought! So I do have myself a drain some where in the car.

Thanks,Bill

 

[rocks66ss]

Thats what I thought! So I do have myself a drain some where in the car.

Thanks,Bill

Just put the light on and remove fuses one at a time until you find what circuit the drain is in, and than you can trouble shoot from there.


Rocky

 

[driver]

Thanks, I was told today by another person that thats not totally correct?
He said since I run a MSD system and a kill switch that I have constant power going to the battery? So it will light up the test light? Any input on that? Thanks,Bill

 

[Ark68SS]

Disconnect the main power to the MSD (big red wire) and see if the light goes off. Then you'll know if that's where the drain is.
BillL

 

[rocks66ss]

Someone with more knowledge about MSD systems will need to help you there. I'm not exactly sure how the MSD factors into finding a drain on your electrical system. Explain to me how you would have power going to the Battery. The only way that happens is if the car was running.

All your kill switch does is break the circuit, just like a light switch, in the on position the car is in the normal run condition. You break the normal flow of electricity than you can't find the drain. The test light will only light if there is something using power. If the MSD is using power while the car sits idle, than the battery will drain.

To give you a simple example, if you put the test light on and it is not lit, open your door and than see what happens. the dome light becomes the source of power drain and the test light will come on.


Rocky

 

[65ragtop396]

It takes 70-80 mA (milliamps) to light a test light. This much draw is enough to drain a battery in a couple of days, and this is the reason the test light test works so well for finding battery drain problems.
If you leave your car with the kill switch in the off (disconnect) position your battery should not drain since the test light does not light with the kill switch off. If it does, there is a problem with your battery, like a dead cell. A load test and/or specific gravity test should reveal this. Could also be your charging system isn't working correctly... what is the charging voltage?

 

[driver]

I took the battery and had it tested which read good. It has 13.2 when running and 12.8 not running. The ALT reads 14 volts. I noticed a few times the car cranks hard (slow) as tho the battery is low??

 

[65ragtop396]

13.2 volts at the battery when running is a bit low (this is above idle speed, right?).
Does this happen when the engine is cold or when hot? If it happens when hot, you may have some starter heat soak going on. Also check the battery cables and connections, at both ends, make sure nothing is loose or corroded.

A fully charged battery, at rest, should read around 12.2 volts. The charging system needs to put out 1.8 to 2 volts more than this in order to overcome the internal resistance in the battery and actually charge it.

 

[driver]

13.2 volts at the battery when running is a bit low (this is above idle speed, right?).
Does this happen when the engine is cold or when hot? If it happens when hot, you may have some starter heat soak going on. Also check the battery cables and connections, at both ends, make sure nothing is loose or corroded.

A fully charged battery, at rest, should read around 12.2 volts. The charging system needs to put out 1.8 to 2 volts more than this in order to overcome the internal resistance in the battery and actually charge it.

Yes, it's above idle speed. I have thought about the starter as well. This all started after putting in a new motor last week. The other motor was 10.1 compression while this motor is 13.1 compression but the starter is built for a high compression motor. I just need to do some more checking.