battery, starter and alternator
roque11
08-14-2013, 10:10 PM
Hi, I'm looking to see if these readings I've had in recent weeks are too low.
Two weeks ago my battery tested at 12.57 voltage and 12.65 the next day. The starter was at 11.23v and then 11.19v. Alternator was 14.06 no load and 14.03 loaded. The next day no load was 13.91 and 14.00 loaded.
Tonight I did a retest and the battery was 12.69, starter 11.37, alternator 13.95 no load and 14.01 loaded.
Are these readings good or bad? I seem to get conflicted opinions.
Two weeks ago my battery tested at 12.57 voltage and 12.65 the next day. The starter was at 11.23v and then 11.19v. Alternator was 14.06 no load and 14.03 loaded. The next day no load was 13.91 and 14.00 loaded.
Tonight I did a retest and the battery was 12.69, starter 11.37, alternator 13.95 no load and 14.01 loaded.
Are these readings good or bad? I seem to get conflicted opinions.
shorod
08-15-2013, 06:33 AM
I'm confused what you mean when you say the starter was at 11.xx volts. The starter does not source voltage, it sinks voltage. Are those readings what you measured at the battery when the starter was engaged, are those readings you took at the starter when the engine was off, or are they readings at the starter when the engine was running?
In general I don't see a problem with the readings. The alternator appears to be charging within the acceptable range and the battery voltage at rest is reasonable.
If the "starter" reading is the voltage at the battery when the starter is engaged, that would be reasonable as well. However, if the "starter" readings are at the starter at the time the battery is at 12.xx V, that would be unacceptable voltage drop and indicate you have a bad connection or bad cable between the battery and the starter.
-Rod
In general I don't see a problem with the readings. The alternator appears to be charging within the acceptable range and the battery voltage at rest is reasonable.
If the "starter" reading is the voltage at the battery when the starter is engaged, that would be reasonable as well. However, if the "starter" readings are at the starter at the time the battery is at 12.xx V, that would be unacceptable voltage drop and indicate you have a bad connection or bad cable between the battery and the starter.
-Rod
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