Engine batteries

Topic: Engine batteries (Read 1140 times) previous topic - next topic

Engine batteries

December 31, 2017, 10:02:16 pm

Went to the coach today to start it and let it run a while before it got cold tonite, I was also checking to make sure the roof heater was on. Well the engine batteries were low on power and would not turn the Cummins over without the boost button. While I was letting things run I did a little snooping around and found the trik l start was not hooked back up when the isolator was changed out in October , so I assume that they lost some power enough to not turn over the motor. So tomorrow I will go back and hook it up. I assume the trik l start will not be enough to charge them back to starting capacity and they will need to be charged .. 1st let me say they are old and were slow to turn over the motor. If I charge them with a portable charger what is the proper way on a 3 battery set up? Can I charge them all together or do I have to separate them and charge them one at a time? Can I run the generator for a while and let it charge them... this is my first rv so be easy on me.

Thanks in advance
Keith

Re: Engine batteries

Reply #1 – December 31, 2017, 10:06:50 pm

All together is fine.

If wet cell, could benefit from an equalizing charge. Best to disconnect before starting.

Then use any "stupid" charger. Monitor voltage or Specific Gravity. When no change in either for an hour, you are done. Probably around 15 VDC (which is why you want the batteries disconnected).

Then let them read and have them load tested.

We are talking about many yours of charging. Yes, you can start with the generator, but not really cost effective.

Re: Engine batteries

Reply #2 – December 31, 2017, 10:24:59 pm

They are optima red tops, and by disconnecting you are referring to from the motor not each other, but I will have to disconnect then to take them to have them load tested

Re: Engine batteries

Reply #3 – December 31, 2017, 10:31:25 pm

If you have access to shore power elsewhere and are going to remove them anyway, take pictures AND label each wire so you can put them back in correctly.

Take them in and charge-- might check with Optima's website for their take on equalization charging. But, certainly charge until voltage is in the mid 14's. Higher if Optima is OK with that.

Wear old clothes (or even better, clothes you don't like) as battery acid is tough on them.

Re: Engine batteries

Reply #4 – January 01, 2018, 07:10:52 am

I posted this in another thread. For any lead battery that is old and fails to crank, I recommend this test:

1. Fully charge, desulphate and do a full, professional load test at NAPA or other competent industrial-strength commercial battery purveyor. If this test fails:
2. Replace batteries.

If you want the full Cold Cranking Amps (CCA) you have to have known good batteries.

When I bought my U270, the coach batteries read 10 volts due to being cooked and required 1.5 gallons of water. I replaced them (one coach buck) because I had a 2,700 mile trip to bring the coach home. I did not want to be stranded because of a battery issue. Engine batteries are even more demanding due to their 1800 CCA requirement.

Re: Engine batteries

Reply #5 – January 01, 2018, 11:28:50 am

If you have to buy batteries, in my opinion, Red Tops are a huge waste of money. I like Johnson Controls batteries like Autozone Duralasts. Mine lasted over eight years and two of them are still good. I just put in a new set of 31 series Duralast batteries although the OEM size always spun the engine well. When we bought the coach in late 2008 I paid about $300 for all of them in North Carolina before we started for home. The latest Duralast were right at $300 with trade in for ALL THREE. When you go to purchase your batteries, ask for a discount. Autozone discounted mine from $117 to $98 each when I purchased three.

Check the weight for any battery you purchase. Sam's Club and Walmart had 31 series for less $$ but were 5 lbs lighter. With a battery, more weight is good. At just over 60 lbs, they are about all I like to pick up.

Do a search and read about Optima batteries. Here is just one: Problems with Optima Battery? | The H.A.M.B.

Pierce

Re: Engine batteries

Reply #6 – January 01, 2018, 01:38:51 pm

Red tops are made by Johnson Controls. I think every unicoach made had either red tops or yellow tops new.

Yes they are more money.

The loud stereo kids run a red top in addition to their car batteries for its instant power production to use on their base speakers amps. Otherwise the alternator needle fluctuates in time with the bass speaker. Some run a capacitor along with the red top

Optima sells a digital smart charger that extends their warranty by a year if bought at the same time. Not our use.

Almost all of us here are running dumb single stage alternators to charge their batteries which costs battery life.

I took Wolfe's suggestion and set my alternator to 13.6 volts max at the batteries and my solar panels ended up at the same voltage.

Shore or gen power is the "smart" magnum charger which will top the battery banks up when used,

All of us really need a "smart" alternator to optimize their batteries life's better IMO.

That way driving would optimize the battery banks charging profile like the newer chargers in the inverters

Re: Engine batteries

Reply #7 – January 01, 2018, 02:29:48 pm

Agreed. I now believe that regular VRLA (Valve Regulated Lead Acid) AKA Maintenance Free batteries are the best for the money. I don't think the spiral-wound techniligy is not worth the extra money.

Re: Engine batteries

Reply #8 – January 01, 2018, 02:30:26 pm

Quote from: Caflashbob – January 01, 2018, 01:38:51 pm

All of us really need a "smart" alternator to optimize their batteries life's better IMO.

That way driving would optimize the battery banks charging profile like the newer chargers in the inverters

Something like this? Xantrex Alternator Regulator

Re: Engine batteries

Reply #9 – January 01, 2018, 02:43:38 pm

Quote from: rvtinker – January 01, 2018, 02:30:26 pm

Something like this? Xantrex Alternator Regulator

Have used that exact model on our sail boat high output alternator for years.

Re: Engine batteries

Reply #10 – January 01, 2018, 03:56:35 pm

How involved would it be to install the xantrex unit in a u320? What's a P type alternator?

Re: Engine batteries

Reply #11 – January 01, 2018, 04:10:43 pm

I've used a Balmar model similar to this one for over 10 years (mine was an older model) and found it easy to install and adjust with magnetic screwdriver they provide. Unit seemed well sealed, must follow directions to not burn unit out. Good product and good support, reasonably priced. Originally it was recommended to me by a marine tech that said he had the least trouble with this brand. Balmar Max Charge MC-614-H Regulator

Re: Engine batteries

Reply #12 – January 01, 2018, 04:51:08 pm

Quote from: Caflashbob – January 01, 2018, 03:56:35 pm

How involved would it be to install the xantrex unit in a u320? What's a P type alternator?

That is what was in mine and almost caused a flash fire. I would not replace with that brand.. If they blow up like mine and several others did it is a potential fire hazard.. That wasnt explained in the manual

Re: Engine batteries

Reply #13 – January 01, 2018, 04:51:30 pm

Would you need two units to be able to temp monitor both battery banks? Interesting comment from Wyatt here about plus 95 degree F needing 13 volts max. Being a desert driver at times....

My small solar setup is not temp controlled either. 13.6 regardless of temp. Same as alternator.

Leece Neville has an adjustable output on its output panel wonder if its worth it to turn down its output for the duration of a hot weather drive in lieu of the temp controlled multi stage charger and disconnect the solar while driving

If I follow this thought farther it might definitely relate to everyone's battery life.

Many here have posted that they have setup their alternators to produce over 14 volts all the time.

Obviously not correct for hot weather. Only time 14 volts is correct is in very cold weather.

The overcharging voltage issue may need to be factored in to reports of various battery bank lengths of service?

My original heart freedom 25 was a serial number below 100,000 so the optional battery temp control hookup was not available. By 1998 the later units could accept the BTS systems.

So the inverter/ Charger makers found it necessary 20 years ago to alter the charging voltage to avoid damaging users batteries.

I definitely would not run 14,15 volts continuously into the coaches battery banks any more regardless of temp.

Yes I know this is more hassle. What if your batteries lasted twice as long? No idea of the actual numbers involved but hours of driving in high temps putting 14+ volts into both battery banks can not be good.

Boiled and killed countless batteries long ago with the single stage chargers then available.

Would seem to be a cost effective over long term versus replacing batteries and the reduction of capacity from overcharging damage could be substantial.

Do any of the solar controllers offer temp compensation?

Sorry for reopening of this idea but.......

Re: Engine batteries

Reply #14 – January 01, 2018, 05:59:01 pm

Consumer Reports test on batteries results showed Sears Gold were the best in 24F, but how long will they be around? Interstate also scored well. Optimas are, in my opinion, a waste of money and I found that their warranty required you to bring them back to wherever you purchased them. Whatever you chose make sure it's a national chain so warranty replacement is easy. Also buy the largest CCA rating available and replace all at the same time.

Keith

Re: Engine batteries

Reply #15 – January 01, 2018, 06:15:18 pm

Yes I bought my optimas from o'riellys

Re: Engine batteries

Reply #16 – January 01, 2018, 06:37:10 pm

Current Consumers Report only tested one Optima. In Group 51r. It was a yellowtop.
Their scores
-Napa 82
-Duracell 81
-Autocraft 76
-Optima 74

Re: Engine batteries

Reply #17 – January 01, 2018, 07:16:53 pm

Yellow top is a deep cycle plus start battery
Red top is start only.

A spiral wound may well sacrifice some capacity for the quicker power delivery as evidenced by the stereo guys use.

Re: Engine batteries

Reply #18 – January 02, 2018, 12:25:16 pm

I replaced 2 of my 3 start batteries in 2012 and the other one in 2013 after failing the load tests. I replaced them with Optima 34M dual purpose blue tops from Napa. The batteries ride on the back bumper and these are designed to take a lot of punishment. I use a TRIK-L-START to keep them topped off. It's probably overkill but I've had zero problems with them. I'll do another load test on them this year but so far I'm happy with them and don't expect any problems.

Jerry

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Engine batteries

December 31, 2017, 10:02:16 pm

Re: Engine batteries

Reply #1 – December 31, 2017, 10:06:50 pm

Re: Engine batteries

Reply #2 – December 31, 2017, 10:24:59 pm

Re: Engine batteries

Reply #3 – December 31, 2017, 10:31:25 pm

Re: Engine batteries

Reply #4 – January 01, 2018, 07:10:52 am

Re: Engine batteries

Reply #5 – January 01, 2018, 11:28:50 am

Re: Engine batteries

Reply #6 – January 01, 2018, 01:38:51 pm

Re: Engine batteries

Reply #7 – January 01, 2018, 02:29:48 pm

Re: Engine batteries

Reply #8 – January 01, 2018, 02:30:26 pm

Re: Engine batteries

Reply #9 – January 01, 2018, 02:43:38 pm

Re: Engine batteries

Reply #10 – January 01, 2018, 03:56:35 pm

Re: Engine batteries

Reply #11 – January 01, 2018, 04:10:43 pm

Re: Engine batteries

Reply #12 – January 01, 2018, 04:51:08 pm

Re: Engine batteries

Reply #13 – January 01, 2018, 04:51:30 pm

Re: Engine batteries

Reply #14 – January 01, 2018, 05:59:01 pm

Re: Engine batteries

Reply #15 – January 01, 2018, 06:15:18 pm

Re: Engine batteries

Reply #16 – January 01, 2018, 06:37:10 pm

Re: Engine batteries

Reply #17 – January 01, 2018, 07:16:53 pm

Re: Engine batteries

Reply #18 – January 02, 2018, 12:25:16 pm

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