Batteries Going Dead

[DerekJ]

I haven’t used my car much in the last couple of years. I keep it on a trickle charge and when I tried to start the car the battery was flat. No great surprise as the battery is about seven years old. I replaced it with a new one, which is the same type, an Optima dry cell model, which are used quite a lot here in competition cars. I cranked the car over just to see it was working and it was, although I didn’t actually start the car. I then connected it to the trickle charger as I wasn’t going to use it immediately. One week later I try to crank up and it was completely dead. I should mention that I have a red key type cut off switch on the dash which was turned off during the course of that week.

So I guess I have a current drain problem somewhere.

What is the best way to go about tracing which circuit is pulling current?

Also, I’m a bit surprised I can have a current drain if the battery cut out is off, unless maybe the switch is the problem?

Any suggestions or ideas?

thanks

Derek

 

[red57]

The one common component you mention is the trickle charger - could it be bad? Have you checked its output?

 

[DerekJ]

Good question. Could it drain the battery instead of charging it?

I just tested the cut off switch and it seems to work Ok. That means there is no current on the other side of the switch so the problem must be befor the switch, or the charger as you suggested. does that make sense?

 

[DerekJ]

The charger is just just a trickle charger for maintaining voltage but it has charged the old battery from 12.8 volts to 13.1 volts overnight so I think it is OK.

 

[DerekJ]

Just had a thought. The start push button switch could be faulty. I’ll check it tomorrow.

 

[John Turney]

Also check the battery disconnect. It kept me from starting many times.

 

[Patrick67BJ8]

Try Repairing the battery. I repaired my golf car batteries. Go to YouTube. Also a episode of Samcrac shows it being done.I forgot which episode, but maybe I can find the info later today.

 

[Bob_Spidell]

...

What is the best way to go about tracing which circuit is pulling current?

...

I just went through this drill with my '96 Ranger work truck that wouldn't hold a charge more than a couple days. There are scads of videos on YT on how to chase down a drain; most are for modern cars with oodles of fuses and breakers, so this is simple on a Healey. This method requires a DVM that can measure DC current; cheap ones only tolerate 10mA or so, better quality ones--you really want to have one anyway--can read up to 10A or more. Basically, you pull fuses or relays and breakers until the draw ceases. A key point, on a modern car anyway, is to let the car settle down before measuring current; the modern electronics can stay alive for several minutes (and most will continue to draw up to 40mA for alarms, lock sensors, etc.).

After several days of not isolating the drain I decided to try another battery even though the one I had was only a year old and tested OK on a digital battery tester (you want one of these, too, much more info than a load tester). The battery was still under exchange warranty and although the parts counter guy was skeptical I got a new one and the it holds charge for a couple weeks.

 

[PAUL161]

Optima batteries take a special charger. (Is your charger made just for an Optima-type battery)? I've been told to never use any other charger on them! I bought an Optima charger and used it once in the beginning to check it but wasn't necessary as the battery was fully charged. The car sets in a temperature-controlled garage, I start the car maybe once a month bringing it up to temp in the winter to circulate the oil and remove condensation, if any. The battery has been in the TF for 5 1/2 years now. I have never used the charger again since the battery has never failed to start the car in that period! PJ

 

[Bob_Spidell]

Optimas are AGM batteries; any charger with an AGM setting--not 'gel/AGM'--will charge them:

https://d26maze4pb6to3.cloudfront.net/optimabatteries/1213/4333/7097/Battery_User_Guide.pdf

My opinion is that battery quality has overall gone downhill (and the prices have gone WAY up). Mike Martinez of Star Electric--who does good work on Brit car starters and generators (NFI)--told me most batteries, including Optima, are now made in Mexico and he no longer recommends them. If I can find them, I'll buy Deka brand, made in Pennsylvania; they're also sold under other brand names, though the one that failed in my Ranger was Napa brand and likely made by Deka. This failure was odd in that it tested good on a load tester and digital battery tester, mine and the store's, but the replacement holds a charge longer. A certain brand--I won't name them but they come in a green and white case--used to be reputable but I had two fail, with no warning and with proper maintenance, in my '08 Mustang (exactly, of course, the length of the car maker's factory warranty).

I got tired of pulling my BJ8's gas tank and neutralizing the spill in the boot and put one of these in many years ago and it's been flawless:

https://www.batteriesplus.com/product-details/auto_light-truck/battery/x2power/sli24agmdp

It also seems that quality voltage regulators are getting harder to find; I have several used ones in my parts bin. Mike sold me one that's worked well with the X2, but, theoretically you'd need a VR set up to work with AGM as they require a higher charge level. My guess is that this VR 'overcharges' just enough to do the job. Smart chargers are good, but if you leave them on for long periods be sure to check the electrolyte levels every month or so,

Now if I could just find a couple Group 17s to put in my BN2