CAT279C with 5000 hours. I’ve had the machine since 4600 hours and I’ve gone through 5 CAT brand batteries. I’ve put in a battery disconnect switch, replaced the alternator to no avail. Every time I get a new battery, it lasts maybe 15 hours and then it acts like a dead battery and will only start with a jump. Battery reads 12.6 volts sitting in the machine, and my battery tester says there is a “surface charge” when it’s in the machine and when out, it says it’s a bad battery with only 400 CCA and a 46% health. Alternator and charging system is working, reading over 14v when it’s running. I got this battery in April and it has 13 hours in the machine. I know CAT will warranty this, but it’s getting old. Should I switch to AGM??
For what it’s worth......I bought a new ASV skidsteer around 2009. Dealer told me to keep the battery disconnected or it will drain when not in use. He was correct; I kept disconnecting the battery to stop the drain. maybe five years later, alternator died. Dealer put a new one in. Still had to disconnect the battery to avoid the drain. Alternator died again maybe three years ago. I put a new one in myself. My battery drain issue went away too. I leave my battery connected now, and it never drains. Even in the dead of winter, it starts fine. It’s just a basic battery; not an agm. so......the alternator or the wiring still may be your issue. It’s possible your new alternator was bad out of the box. Sounds like the alternator isn’t charging if the battery shows good voltage when not running. Is the alternator belt tight?
how often do you run the skidsteer and for how long? 14V is plenty running. 15 is getting too high. agree the alternator is the usual suspect if there's no computer draining the battery, and equipment was better than cars/trucks for a long time, maybe not so much anymore with ecu's etc on equipment too. Does a new battery hold a charge for several weeks with your disconnect? wondering if it's installed correctly? that is, no bypasses. Worst thing for batteries is constantly being undercharged. a battery tender and a disconnect is belts and suspenders for your battery's pants.
When you check the voltage with the engine running are putting your voltmeter leads on the battery posts or are you taking the readings from cable ends ? 5 new batteries indicate dirty or corroded connections, or a combination of the previously suggested problems. Are the batteries being boiled dry from overcharging ?
The alternator belt is tight and maybe you are on to something. Maybe the alternator is feeding all the machine's needed electrical needs when the machine is running, but not in fact charging the battery. I need to test that.
Yeah. that's on me. I bought a battery tender for this (NICO) last year when I had the last bad battery and I just never installed it. I just got back from the Cat dealer and they gave me a new battery after verifying that the battery was bad. I am absolutely installing the battery tender at the same time I replace the battery. Just curious how the battery could be installed wrong. What should I be looking for? I have the master disconnect in between the battery negative and the frame ground. All my testing shows that 100% cutting all voltage.
I meant the disconnect installed wrong, if you have the voltage 100% off, then that's what you want. If the BATTERY POSTS are at 14V when running, then the battery should be charging. Whether it wants to charge or not is the battery's problem, that's plenty of voltage to push the amps if the battery will take them. And none too many volts to boil the battery unless you're running 12/7 at more than 14.5 and/or the battery is in a really hot location. how often do you run the skidsteer and for how long? If you use the disconnect and put it on a tender every time it sits, the alternator could just about be removed and throw out. I guess you'll see what the new battery does.
I'm a homeowner with lots of land so it's not being used everyday, but i would guess that I use it once a week for about 4 hours at a time.
That's a perfect schedule for the battery to last ten years, no excuse for needing a disconnect switch, much less a charger.
If the Caterpillar dealer gave you battery #6 and said it was defective he may have had an unusual bunch of crap batteries. Those dealers don't normally keep trading batteries. Alternator belts can get a glaze on them and no amount of tightening will get it turn an alternator under full load. It would be unusual on a serpentine belt if that is what you have.
i agree with TINKERER- you should check the charging voltage at the batt posts in case you have a voltage loss in the cables or connections. for instance, if you check the charging voltage at the alternator output post and it is 14.5v and the voltage at the battery posts is 13.5, you have a poor alternator wire, batt cables, or connections. you should only have .5v max voltage drop between the alternator output and the positive battery post. and don't forget to check the negative(ground) side as well for poor connections etc
Update: got my new battery installed and the Nico battery tender. When running, voltage at the battery is 14.53. When not, 12.7.
I would sure like to see a millimeter connected between the pos. battery post and the cable while the machine is not running. Just to see if there is a parasitic draw somewhere. If there is one it would be interesting to track it down. Probably the alternator I would guess.
I have ruled out a parasitic draw, and installed the battery disconnect. I'm good there. All I can think at this point is either I've had bad luck with batteries, or there's a unique vibration or something that is killing the regular batteries and I'll need to go AGM. I'll be watching this new battery like a hawk.
One thing I am even hesitant to mention here but I will anyway. After I installed the battery, and before I installed the tender, I tested the battery at different locations. When I tested it at the positive post jumper block in the rear by the engine door, and grounded the black wire on the engine block lift hook, I got a Voltage reading of 36v...numerous times and even after making sure I had a good connection. It did read back to 12.7v when I took it all off an put it back on, but what in the world would cause that reading?
What did you do to rule out a parasitic draw ? I am not questioning your conclusion just your method.
One thing a battery does is smooth out the voltage spikes, both high and low. I can't figure out for the life of me how or where 36 volts would come from. I wonder if there is a capacitor somewhere in the system?
I measure across every fuse and then installed the master disconnect on the negative side.
Did you remove the fuse and actually measure the circuit ? The millimeter has to be the bridge in the circuit. That is why I always start between the battery post and the cable that is disconnected.
most multimeters can only handle a small current-maybe 10 amps or they may blow the internal fuse or overload protection (if it has one). i just touch the cable to the post first-big spark equals bigger current----small spark equals small current that your multimeter may be able to handle without damage. if you have a multimeter with an inductive current pickup attachment, use it first just to give you a rough idea so you don't overload your multimeter
Yes, I removed the fuse and measured across.