Hey guys,

I've owned a few cars over my lifetime that I've stored over winter. I just start them about every two weeks, let them idle 15 mins, and never have any problems until recently.

This winter, I let my 93 Rx7 sit about 4-5 weeks without starting. By the time I went to start it, it was completely dead. I jumped it, let it idle 15 mins, then let the car sit another two weeks.

Again, the car was dead after this two week period. I jumped it, let it idle 15 mins, reved it at various rpms once warmed up. I tried starting it again only 5 days later to find it dead (not completely this time, but still not enough juice to start).

Do you guys think I am not letting the car idle long enough for the alternator to fully recharge the battery? Or maybe my battery just needs replaced? Isn't it hard on the alternator each time I jump start the car? Also, should I disconnect the battery while the car sits in storage, and if so, do I disco both terminals?

Thanks,
Tony
93 Rx7
94 Camry

 

You should disconnect the battery when storing it. However, in the past, I have let my FD sit for months with the battery connected and never had a problem.

It could be your battery just needs to be replaced. You might also check places like your glove box, hatch or other places that might not close all the way and put a drain on your battery.

 

Mahjik: Thanks for the quick reply Would I need to disco both battery terminals?

Tony

 

disconnect the ground you dont have to disconnect both

 

Also, 15 min. isn't enough to charge a dead battery. Use a good quality charger, and leave it connected for min. 8 hrs. Make sure the voltage doesn't go over 14.5 or so. I recharge mine every 2 weeks. I use a constant voltage current limited charger.

It's really hard on a 3rd gen to start it in winter (temps. below freezing). The oil is too thick and when the turbos spin it can trash the bearings because the oil can't flow properly until it warms up.

 

Go to Interstate Batteries and get one of these for each car you own. It a trickle charger. They go for 30 bucks each. It takes the hassle out of disconnecting **** and takin out batteries, and jumping. Keeps your battery nice and new. It puts a constant low charge on them, and once it falls below a certain voltage it automatically kicks in to a higher voltage till they come back up, when they come back up it automatically goes back to the lower voltage. I works great and I got a mini battery.

 

Battery's (non deep cycle) need to be exercised. Letting them sit will cause the led plates to oxidize. A non conductive film will build up and restrict the internal chemical reaction needed for a battery to operate to its potential. I would use the battery once a week or so running the lights or radio a bit, then charge the battery with ether a trickle or normal rate charger. I would charge at a low rate around 10 amps. NO reason to heating up the battery. I have worked in General Motors dealers doing tune up and electrical for 20 years and have never seen the Battery capacity test in any manuals or during any training sessions/classes. The test is simple to preform.
Charge the battery at around 20 amps, connect a volt meter and watch the voltage rise. The battery voltage should not exceed 15.5 volts in the first 3 minutes. If so the battery will under preform. It may pass any other test you give it but still fail in service. If your not sure keep the charger up to an hour or so and if the voltage goes over 16 volts again it should be replaced. The simple idea is if a battery will take a charge too quickly it will louse it fast as well. The typical symptom with this type of conduction is a no crank after sitting overnight. Now you could have a subsystem screwing up and drawing higher levels of current with the key off and that should always checked. Typical draws are under 100 MA. The battery capacity test has "never" left me out in the cold.

 

I thought about the trickle charger route, but problem is I live in a condo building where the car sits in a common parking garage. Because the outlet is far from my garage space, I'd have to run the electrical cord across the garage and in front of several other people's cars, possibly causing them to trip.

Given this, might it be best to jump it once more, run it longer (say 30 mins), then shut it off, disco the battery, and then hopefully it will start on its own once/week?

BTW, my car is stored in a 50 degree heated garage.

Thanks,
Tony