Specific Gravity varied widely after topping up.

I am in Coastal San Diego. Rarely drops below 40f.

Cold temperatures thickening oil are not a factor in my engine starting, and even with weak batteries the engine has no issues cranking in the morning. I usually just use only the 7.5 year old wally world 27 to start it, and after 20 seconds or so, bring in the depleted Crowns to the alternator circuit. My Ammeter goes from ~7.5 amps, to ~58 when I turn my battery switch to both in the morning and more rpms will send the amps up into the 90's

Cold weather thickens the oil in your crankcase and oil pump on your motor. It's normal for it to crank a bit slower in colder temperatures. When is the last time you changed out your motor oil?

Yes, access to my house batteries is a bit complicated, and uncomfortable on my neck and knee's.

I have been plugging in only rarely. I probably will tonight as I have some 18650's to refill as well. Sometimes My schumacher brings them into the 15's with 9 to 11 amps for a few hours and goes way over my amp hour counter 0 from full, other times it decides 14.7 for much less time is plenty and illuminates the green light, kind of agreeing with the Battery monitor within a few A/h. I'd say I plug in 3 times a month and every 4th time plugged in, it does an EQ cycle.

Still need to acquire an Iota or PD to replace Schumacher.

These past two sets of Crowns have used lots of water, much more than previous batteries. The rate of loss is increasing as they age.

My house battery box kind of stuffed to the gills with 2 27's, the limiting factor being length of 2 batteries side by side. I need 26&1/2" and perhaps more for 2 group 31's, I have 25&5/8". I've had to modify the battery handles so that the 27's fit.

MOdifying the battery box is not going to happen, it is a mistake I will live with, and honestly I've never needed the full capacity I've carried around for the last 5 years.

I'm seriously thinking of 3 agm's in parallel always via my Guest manual switch. The Engine battery is ~20 feet away, from house battery, total circuit length over 2awg wire. So it will not be a perfectly balanced battery bank. Perhaps I can rotate them yearly.

The crown DC27s are 115A/H when new and 62 lbs each, 230 AH total. I pretty much never take more than 70A/h overnight.

If I get 3 marine DHP group 34's for a total of 204 A/H I'm still not taking these Figurative 3 batts below 50% in normal usage Even just 2 in parallel is only ~50% DOD

lets Say my Crowns are rated at 600 CCA each, and my WW 27 is 650. All three together, 1850 CCA 345 A/H for 176 lbs

Thr 3 DHP' group 34 will have 2640 CCA 204 A/H total and 159 lbs.

My engine always starts easy, Only requires a single 650 CCA starting battery and my 7 tear old 650 cca battery has no issues.
I don't think even reducing my overall capacity is going to affect me being able to start the engine. 204 a/h of agms with 100 a/h removed from them probably still have more CCA then 345 A/H of flooded deep cycles with 100 a/h removed.


I occasionally forget to isolate my engine battery now, and cycle it with the house, and the engine still cranks fast and with authority first thing in the morning, but certainly not as fast as later in the day when engine is warmer and solar has all 3 batteries up in the 13 to 14 range.

I'm more worried about The 3 hungry AGM's together overwhelming my poor alternator, as I have fatter cables direct from alternator to battery switch, in parallel with original circuit path

Agreed about your need for AGM, if access is a nightmare.

They are no longer teetering on the edge of a cliff - the ground is rushing up. fast.

AGMs are what you need with that access problem in that RV. Big PITA having Wets in there now

IMO you did well keeping those damaged batteries going. Yes, replace them now before winter. ISTR reading that batteries fade quickly at the end.

Hi,

I would replace them--but not with lower capacity. I'd get three identical batteries. I'd add a trik-l-start for the chassis battery.

When did you last equalize/desulphate the bank?

landyacht318 wrote:

Thinking bout replacing all 3, at once, with smaller/ lower capacity AGM's, cause I've had a lot of work lately, and watering( lack of) has been my primary battery killer over the last 5 years.

That sounds like a good plan to me.

Update:

With the somewhat colder weather kicking in, and now with the time change, my usage has gone up, and the voltage under load is dropping into the 11's well before I goto bed, and I am waking upto ~11.7 with 11.5 minimums recorded with ~60 A/h removed from the batteries.( 2 group 27's, 115A/h each)

Nothing is not working properly at these voltages. They are still accepting 60 to 90 amps when I start the engine and bring them into the alternator circuit, but their voltage does climb higher quicker under such current than before.

I can tell that when they are fully charged and I have all 3 batteries cranking the starter, it cranks much slower than just a few months ago.

I'm just wondering how long I am going to push these. I think they are perhaps teetering on the edge of a cliff. As I type they are at 12.1 under a 7.8 amp load @ 30a/h from full, and the alternator was just feeding them 90 minutes ago.

My Wally world dc-27 engine battery is due for replacement too at 7.5 years old.

Thinking bout replacing all 3, at once, with smaller/ lower capacity AGM's, cause I've had a lot of work lately, and watering( lack of) has been my primary battery killer over the last 5 years.

Considering just leaving a future 3 in parallel always with the option to disconnect the engine battery if/when I start drawing them into the starter "click" realm, which honestly, has not ever been an issue, not since I've gotten solar.

Deleted.

Hi Landyacht,

It is not the temperature that causes the issue. H2S04 has a greater volume as the state of charge increases than water.