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Trojan Battery Info and Tips

Tom Cherry

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Note....the moderators and myself ask that all replies stick to the INFORMATION presented.  This is not, nor will we allow it to be, morphed into a discussion of why Flooded Batteries are buggy whip holders or why they are the best thing or a discussion of the merits of AGM or Lithium.  This is strictly informational for the 75% or so that still have or still prefer flooded cells.  

OK....now that we got that out of the way.  Over the years, we (the moderators) and several other folks have tried to provide helpful information on how to maintain and/or test flooded cell batteries.  There are certain of us that have biases as to which brand to buy....  Trojan ranks as MY best and others concur.  Some say....cheapest you can find.  OK....without debating the brand merits....I am going to do a short review, as informational, of what I have learned and confirmed again.  Since we all will be getting our MH's out and doing the spring stuff....I thought it was timely.

Be AWARE... copious amount of Caffeine may be required....but here goes.

I have (if you read my post) a gremlin in my Hydraulic Slide circuit that I THINK is a high resistance connection   It vibrates and sometimes the slides are flawless and the other times I have to actually push or help them.  The "tech" (name witheld) that sold my buddy a $2800 "In Motion" sat dish and tore off his old Kingdome and installed an SD ONLY in motion unit rather than putting on a Winegard Traveler so he could get HD on his DT System.....was NOT a lot of help.  His first fix....How old are your batteries.  7 years and starting into their 8th season.....  Go get new ones....they NEVER LAST.  I know some very smart folks that post here that have Trojan T-105 that are about the age of mine and we never have had issues.  The tech refused to even discuss anything else....and when I gave his voltage and Specific Gravity readings and such, his eyes glazed over.

Bottom line, my Trojan T-105's were installed in the spring of 2013.  I have exercised them religiously for about 4 or 5 years.  I have the Pulse Tech units that defultonate them.  In the spring of 2018, I load tested them via a know amp hour load and then after calculating the amp hour drain, checked the SG and voltage and they were about 90%....or they would ONLY take or provide 90% of their rated capacity.

This year....they are down to 75%.  SO....I decided to get new ones.  Doubt I will dry camp that much....but I now have a Samsung Res Refer and don't need the hassle.  I DID win a mini lottery (NO....it was just an unexpected windfall....I got a refund on my unused ACC Tournament Tickets and decide that money...which was already "spent" would be used for new batteries as I located some at a great price).  

OK....before I pulled them, I was able to do the circuit trouble shooting that Frank (Mr. Wizard) M had suggested.  i pulled all shore power.  I must have cycled the short hydraulic slike in and out 15 times.  The old Trojans still were healthy.  I had exercised them before our last outing and I knew that they were "Fair to Good or 75%).  They came through with flying colors.

OK....got new T-105.  Curiosity....  Did the voltage and SG testing.  The batteries were 6 months old and had been sitting under a shelter in a golf cart shop.  I called and talked to Trojan Tech Support and he and I discussed them and maintenance and my practices.  

The new batteries, as expected, were discharged to around 80%.  My SG Meter ($20) from Amazon is calibrated nicely.  By measuring the "sitting" voltage....he confirmed that the SOC was 80%.  AS EXPECTED.  The SG readings that I got correlated (1.2375) with the Voltage of 12.25 or so.

So, my SG meter is correct.  His advice.....INSTALL THEM....and Charge them.  He understood that I have a Magnum inverter charger with 3 stage charging.  That was GREAT.  BUT, he said they needed to be used....or they would not be properly exercised.  Most of the time, these are going into golf carts and then you run it down and recharge.  BUT, if I were going to put the MH into storage....that I needed to probably (not required....but recommended) run them down a time or two to get the SG to equalize.  I will do that.

We also talked about electrolyte levels.  The Trojans were filled from the factory at the bottom of the well.  That measures 7/8" from the plates to the bottom of the well.  I have a wooden dowel that I use as a dip stick gage.  I have a "fill" line that is 5/8" from the bottom.  He said that after you used them, that you should replenish the level and NOT fill to the bottom of the well.  He recommended the MAX at 1/8" BELOW the well line.  That would be 3/4".  Since I was using a 5/8" fill line, he was totally cool with that and said that would be what he would have told a customer.

One final note.  I have NOT serviced (shame on me) the MH since May, 2019 due to my injury.  BUT, my electrolyte level was 3/8" or right at HALF.  That is ONLY due to the Water Miser caps that Mr. Wizard recommended and many of you use.  SO....I got 7-8 years out of my Trojans compared to 4 years on the OEM Interstates.  I have posted that one of the Senior electric techs at Lazy Days that that one you dry out or let the level drop on the Interstates....they are TOAST...but if you refill the Trojans, you have about a 75% chance of them recharging and getting a few or maybe several more years out of them.  He used the Timex line....Takes a Licking and keeps on Ticking.

That is about it.  Hope this is of interest.  It is intended that way.   Happy spring maintenance (like us retirees have anything else to do...).  I have set up a perimeter and will be in self imposed "Quarantine" until all this ugliness passes....I will make an appoint to drive across town and see my GK's in May....


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Thanks for posting Tom.  I'm expecting to be replacing my 2013 Interstate Flooded batteries this year before we head out west and have to boondock at the Balloon Fiesta.  I'm waiting to see if Sam's Club puts their Duracell 6v AGM's back on sale hopefully before this Fall.  It sounds like from your experience that you advocate using flooded batteries instead of AGM's.  I'm still a little on the fence about them.  I currently go top off my batteries with Di-Ionize water once a month with my 8 house batteries taking about 3/4 - 7/8 gal.  The Pro-Fill system helps but I know I have over filled them on occasion.  I really don't look forward to wrestling with replacing eight 70 pound batteries.  😉

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Your call on whether you stick with flooded or go AGM.  I put mine in in 2013 when I did the same trip you are making.  MY MISTAKE was not annually exercising or dry camping.  IF I had done that prior to my "Enlightenment" circa 2016, my old workhorse Trojans would not have been replaced.  75% Max SOC was a bit puny.  

Personally, I would do some price comparisons.  IF I could get Trojans for say 20 - 25% more....then that is a no brainer.  I did debate about whether, at age 75, I will be doing all the things we did in the last few years....BUT, doing the Balloon Festival is probably one we will repeat.  SO, it was Trojans and use that as an advertising point if I decide to sell the Camelot.

If you follow what I learned, from our Mr. Wizard and also Trojan, you should have NO issues.

I SHOULD have said...but GOD...would that have opened a can or worms....  a sustained MEDIUM to LOW drain (as in only some lights and a res refer) can be safely taken down to 11.8 on the Magnum.  The actual voltage....after years of verification will be around 12.0.  Also, occassionally, you can go lower.

Magnum says to LET THE BATTERIES stabilize for at least an hour with NO LOAD (disconnected).  THEN measure the voltage.  BUT, if you have a good calibrated SG Meter, then you can use that to determine the SOC.  I had a basic SG meter and upgraded.  Sure enough....when I measured the new Trojans, the Voltage and the SG readings were corrrelated perfectly.

The REAL SOC measurement or condition is the RESTED for an hour Voltage or the immediate SG reading.

Hope this helps you....if you have 2013 batteries, this ain't your first rodeo.....



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