DanG144
Top Post Dawg
Do rdkern's battery voltage check first.
Using a multimeter to directly measure the resistance of high current carrying cables is not the best way to test the wires. Even one strand making good contact will give you low resistance, but it cannot carry the required current. (and your resistance is much too high, anyway; a starter pulls hundreds of amps, 300 amps times .5 ohms total resistance is 150 volts... you see the problem? Or to put it another way 12volts divided by .5 ohms = 24 amps, and you need 300 amps. Remember V=I*R, V/R=I, etc)
The best way to check heavy cables is to measure voltage drop under high current load.
So while trying to start the car measure the voltage from:
1)The starter solenoid (heavy wire from the battery) to battery + (good if near zero)
2) The starter solenoid (heavy wire from the battery) to Battery -(good if near 12 volts.)
3) The transmission to battery - (good if near zero)
4) Chassis ground to battery -(good if near zero)
It sounds as if your cable resistance is high. It should be zero when measured with a multimeter.
Clean all high current connections. (Battery +, -, battery to chassis ground, starter) Check the cable ends where they go into the lugs. If one is getting hot when cranking, that is a problem. Many people report bad connectors on the solenoid end of the heavy cable from battery +. Clean the grounds under the battery, and on the transmission.
Dan
Using a multimeter to directly measure the resistance of high current carrying cables is not the best way to test the wires. Even one strand making good contact will give you low resistance, but it cannot carry the required current. (and your resistance is much too high, anyway; a starter pulls hundreds of amps, 300 amps times .5 ohms total resistance is 150 volts... you see the problem? Or to put it another way 12volts divided by .5 ohms = 24 amps, and you need 300 amps. Remember V=I*R, V/R=I, etc)
The best way to check heavy cables is to measure voltage drop under high current load.
So while trying to start the car measure the voltage from:
1)The starter solenoid (heavy wire from the battery) to battery + (good if near zero)
2) The starter solenoid (heavy wire from the battery) to Battery -(good if near 12 volts.)
3) The transmission to battery - (good if near zero)
4) Chassis ground to battery -(good if near zero)
It sounds as if your cable resistance is high. It should be zero when measured with a multimeter.
Clean all high current connections. (Battery +, -, battery to chassis ground, starter) Check the cable ends where they go into the lugs. If one is getting hot when cranking, that is a problem. Many people report bad connectors on the solenoid end of the heavy cable from battery +. Clean the grounds under the battery, and on the transmission.
Dan