2000 Chinook engine battery died on trip.

[Astrodokk]

I charged my engine/starting/chassis battery a day before I left on a three-day road trip.
It did not start my engine the next morning, but I could hear some clicking when I turned the key.
Nonetheless, the rig started with the boost assist button on the cab ceiling, and I had to use that for the whole trip.
Later that day, I stopped at O'Reilly's and told them the circumstance. They tested the battery and it said "good", (probably from my charging the previous day).
We were plugged into shore power the first night, so I was able to enjoy the mood lighting and coach stereo.
The second night was at a different site with no hookups. I was concerned using anything in the coach because I felt I needed the juice to start the engine in the morning. In fact, in the morning, I tried to turn on the coach stereo and it did not even light up, and that concerned me a lot.
Luckily though, the booster fired up the engine very well.
I took the rig to a mechanic on the way back home. They tested the battery, and it was dead, but then they said that they thought the alternator was bad because of the voltage it showed and some code he mentioned.
My question is, what alternator should I replace the old one with? Should I just take it to a Ford service center for OEM?
I'm thinking that it is the alternator, and if it is, the old battery should hold a charge after charging, and if not, I'll just buy a Red Top and call it good if all goes well.

[caconcourse]

We had to replace the truck battery on a trip once. It was old and just wore out. I could never get the Boost function to work when the truck battery was low, and I found out when I removed the separator to put in lithium batteries, a rat had chewed the boost wire in half!

From the factory, one of the two coach radio power wires is connected to the truck battery in many Chinooks, including my 2001 Concourse. Our radio died when the truck battery died. After I upgraded to lithium batteries, I rewired the radio to run completely off the coach batteries.

The alternator may or may not be bad, but if replacing, use a high output alternator (> 130 AMP) to handle the coach battery charge load. I think the high output alternator was standard on our cutaway chassis.

I would replace the battery first, your old one is probably weak now from all the discharge cycles, even if it was working. You can test the alternator output by measuring the battery voltage while the engine is running, should be over 14V.

[Astrodokk]

Thanks for the advice.
It seems that the coach stereo may indeed be connected to the truck battery, as it did not turn on (and it's new!).
I had thought it was only connected to the two coach batteries. But even so, would the stereo not be able to function with only the two good coach batteries connected? Or does the stereo need both connections (truck and coach batts in together) to be able to work?
I had also been told a while ago that regulators/separators go bad and to carry a new one for emergencies. I was thinking that perhaps it could be that causing the issue.

[chin_k]

I don't think you need to carry a spare separator unless you already have the entire spare engine stowed away somewhere. Just carry a spare jumper cable, or use one of those lithium pocket size jumper. Unless you have a diesel engine, that may take more CCA to get started.

For the battery, the engine need to have a lot of amp to crank the starter motor, which is not idea way to use the coach batteries. That is why you have a chassis battery for that. For the coach, the chassis battery is not meant to be drawn down to 25%, so that is why you want deep-cycle batteries for the coach. The chassis battery is meant to be recharged right away after starting the engine. It is the specialization that each battery type is for.

If you do not use your rig for months, either disconnect the battery negative terminals, or periodically use a trickle charger to top it off if you are near a shore power outlet. The reason is that, as mentioned already, the chassis battery must be close to fully charged almost all the time to achieved expected life span.

[caconcourse]

Thanks for the advice.
It seems that the coach stereo may indeed be connected to the truck battery, as it did not turn on (and it's new!).
I had thought it was only connected to the two coach batteries. But even so, would the stereo not be able to function with only the two good coach batteries connected? Or does the stereo need both connections (truck and coach batts in together) to be able to work?
I had also been told a while ago that regulators/separators go bad and to carry a new one for emergencies. I was thinking that perhaps it could be that causing the issue.

The stereos have two power wires, but they are not redundant. One is supposed to be "always on" to maintain the radio settings, and the other is tied to the ignition, and is on when the key is on. Since there is no "ignition" for the coach stereo, that wire is just tied to the 12V system. The "always on" wire is connected to the truck battery. This is one of the main sources that drains the truck battery over time during storage. How the stereo uses the power lines depends on the manufacturer. My stereo would not work when the truck battery power was removed, which is probably the same as your case. It probably needs both to have power for all of the functions to work. When my coach batteries were dying overnight, my radio would turn itself on in the morning when the solar kicked in, as the LVD cut power and solar brought it back, so the radio power cycled and turns on at power up by default.

I would guess again that your problem was just caused by your truck battery getting old and weak. You don't seem to have trouble with your coach batteries charging. If they recharge while you are driving the alternator and separator are probably fine.

[Astrodokk]

Thank you.
Today I will buy a new truck battery. I heard that the Red Tops are good.
Then, I will get the alternator checked, and if it falls below a certain parameter of performance, I might as well replace that too.
Also, I'm thinking of replacing the 50W solar panel with more wat6tage, but that will fit in the small area up on the roof.
Anyone know of a higher wattage replacement solar panel that will fit the same space?

[chin_k]

What is the voltage when the engine is running? It should give you a good idea if your alternator need to be replaced. Sometimes, you just need to replace the regulator on the alternator, for example.

I looked very hard for newer panel that can fit in the same area in past few years, but it is very difficult to find because it is not efficient use of the space from the manufacturer's view. Square is the best use of material, for example. I end up getting a slight wider version and just deal with having overhang on the side of the rig and call it a day. If you do come across something that match, let everyone know for sure. Good luck.

[Astrodokk]

What did you replace the 50W solar panel with?
I don't mind if it overhangs a little. I want the function, not the cosmetics (to a limit that is).
My deep cycle batteries are relatively new (bought in Reno while on a road trip in 2021). But I don't want the single stage Magnatek 7345 to boil them, so I'm also looking at replacing this charger. The PD 4645 is what I've read as a plug and play, but I've read posts that state that the PD 4645V version is not so easy to install. Are the two different?

[caconcourse]

What did you replace the 50W solar panel with?
I don't mind if it overhangs a little. I want the function, not the cosmetics (to a limit that is).
My deep cycle batteries are relatively new (bought in Reno while on a road trip in 2021). But I don't want the single stage Magnatek 7345 to boil them, so I'm also looking at replacing this charger. The PD 4645 is what I've read as a plug and play, but I've read posts that state that the PD 4645V version is not so easy to install. Are the two different?

I have a PD4645 you can have if you send me your shipping address via DM. I replaced it with the lithium version (LIV) so i don't need it anymore. It originally came with the shell, which probably made it a little easier to install, but my LIV replacement only came with the circuit boards, so I reused the shell from the last one. This is probably the difference you were referring to. You should be able to replace the Magnatek board with the PD4645 in the original shell. You may or may not have to drill new mounting holes but should be easy.

I'll add a separate post showing my solar upgrade.

[caconcourse]

What did you replace the 50W solar panel with?

I kept my original 50 (55?) watt panel and added a second one behind it that I bought from another owner that had upgraded. Then I added two 55 watt flat panels on top of the air conditioner shroud and the flat area right behind it. So I have a total of 210-220 watts. I also upgraded the controller with this Coleman model: https://www.amazon.com/gp/product/B004R ... UTF8&psc=1 which covered the opening nicely (had to shave the edges of the opening a little). These are the panels I bought: https://www.amazon.com/gp/product/B09BJ ... =UTF8&th=1 These new panels are more rugged and supposedly efficient that the flat panel I had previously used. I have all four panels wired in parallel so that one being shaded doesn't affect the whole array.