Outdoor Adventure USA

What is a good way to determine if my Yellow Top is reaching end of life?

CactusJK wrote:What is a good way to determine if my Yellow Top is reaching end of life?

Have it tested for capacity and internal resistance. Testing the battery with a voltmeter will not give you a complete picture. Most battery specialty stores and garages will have the testing equipment to check the battery's health and capacity.

CactusJK wrote:What is a good way to determine if my Yellow Top is reaching end of life?

When the battery doesn't seem to hold the charge like it used to, then its toast. I replaced my yellow top with a red top yesterday (in my mustang, not jeep). I killed my yellow top by letting it get super dead at least 5 times. (and its 7 years old). The red top has 1000ca.

jgorm wrote:

CactusJK wrote:What is a good way to determine if my Yellow Top is reaching end of life?

When the battery doesn't seem to hold the charge like it used to, then its toast. I replaced my yellow top with a red top yesterday (in my mustang, not jeep). I killed my yellow top by letting it get super dead at least 5 times. (and its 7 years old). The red top has 1000ca.

7 years on a yellow top is awesome...a red top is a better choice for a starting battery than the yellow top - more cold cranking amps, and (usually) a longer life.

IMO, just feeling a battery is not working as well as it used to be is not an effective way to tell remaining battery life of a deep cycle / AGM type battery. The yellow top is designed fro 500 charge cycles, and an average life of 2-4 years. Best way to check is on a meter that tells both voltage and internal resistance changes (health). You can have a battery with full voltage, and yet no available amperage under load. It could die very quickly, leaving you stranded....

Part of the reason i wanted the red top is for more "rush" current. On my mustang i was getting a voltage drop while at full throttle and I'm hoping that the drop will be less with this battery. While it may be better to test the battery, my "feeling" has worked well. When i hear the starter go a little slower than normal, the battery has a couple months left. On my camper i have a "trimetic" (sp) and it shows all the battery stats. When the batteries start to die faster than normal, then its time to replace them. Its not really that hard to "feel" a battery on its way out if you are tuned into the warning signs. Keep the batteries charged up and they will last WAY longer.

jgorm wrote:Part of the reason i wanted the red top is for more "rush" current. On my mustang i was getting a voltage drop while at full throttle and I'm hoping that the drop will be less with this battery.

You are correct that the red top has more CCAs ("rush" current). But, if you are getting a voltage drop in the system when it is running, it is not likely the battery at fault - it acts as a capacitor once the vehicle is running, and if it's charged, has no effect. Of course, if the battery is bad, the alternator works harder to keep up; but the battery would have to be pretty dead, not just on it's way out, to cause a voltage drop from system charging. Could be a voltage regulator on it's way out...

You sound like a skilled technician; but most folks are not that sensitive to their vehicles minor changes. My point about getting the battery checked properly is that most can't "sense" a battery going bad, and most batteries will not give you a warning when they fail. So, it's a good idea to have it checked on a meter regularly, just like checking tire pressure is better that guessing if the tire is inflated properly.

cruiserlarry wrote: You are correct that the red top has more CCAs ("rush" current). But, if you are getting a voltage drop in the system when it is running, it is not likely the battery at fault - it acts as a capacitor once the vehicle is running, and if it's charged, has no effect. Of course, if the battery is bad, the alternator works harder to keep up; but the battery would have to be pretty dead, not just on it's way out, to cause a voltage drop from system charging. Could be a voltage regulator on it's way out...

Its sort of a complicated issue. There are no voltage issues at part throttle, but at WOT i see a ~1v drop from the start of the pull to redline. It did this with the new yellow top, and was not part of my "battery is toast theory". Part of it is probably due to spinning the alternator backwards (needed to flip it to clear the blower), and the other part is the additional fuel pump, bigger injectors, etc. I have seen may other mustangs exhibit similar symptoms, with some much worse than others. Its not a huge deal, but I'm pick and like my voltage above 13.5 at all times.

jgorm wrote: Its sort of a complicated issue. There are no voltage issues at part throttle, but at WOT i see a ~1v drop from the start of the pull to redline. It did this with the new yellow top, and was not part of my "battery is toast theory". Part of it is probably due to spinning the alternator backwards (needed to flip it to clear the blower), and the other part is the additional fuel pump, bigger injectors, etc. I have seen may other mustangs exhibit similar symptoms, with some much worse than others. Its not a huge deal, but I'm picky and like my voltage above 13.5 at all times.

Yeah, there is a certain security to having a constant full voltage running all the time. Interesting, 'cause many of the trail rigs run tons of current drawing accessories - probably pulling more current than the injectors and fuel pumps - but rarely use WOT for more than a few secs...I wonder if the FJ or other vehicles would have the same symptoms in the same scenario...Just one more thought to occupy my over-charged and under-voltaged mind...