black_88

well I bought a 1988 n/a rx-7 and it had a dead battery. so I went and bought a new battery which I was told was the right one. and the one that was in it was a 900 cranking amp battery and the one that was put in is 525 cranking amps. so when i went and tried to start my car a couple days ago and it whould not start. and when I looked at the battery it was a lot smaller then the battery tray. so is the car supposed to have the 900 cranking amp one or the 525 amp one.

Richter12x2

iTrader: (1)

I don't remember exactly, but it wasn't 900 - in fact, I've run it off the battery from my little Mercury Capri convertible - a BMW 326i, and ran it using one of those little quick jumpstart battery boosters and no battery. If it doesn't fit the battery tray, it's probably not the right one for your car. In a pinch, check the Mazda parts lists - someone's got them somewhere, I'm sure - the description should tell the specs on the battery.

Patman07

summit has those red tops that putout like 725 or something, surely would start an rx7 onsale for 150 i think. Only if you like optimas I guess.

Turbonut

iTrader: (1)

525 is fine. Original battery is only 55 amp/hr, or in a cold climate 65 amp/hr.

NCross

iTrader: (18)

mine is like 795 i think. the old battery was 500 or so and i could tell a huge difference after i swapped it out.

black_88

see the thing is I put in this new battery and it started by it's self twice on the same day. but then I left it for two days and the battery died. so now the only way to get it started is to jump start it. so I got the idea to drive it around for a little and charge it up and then take it out. so I drove it around and killed some civics (stuiped ricers) and when I got back home I pulled the battery out of the car and put it in my house. so the next morning I put the battery in and it just barley turned the car over. the car's volt meater is charging at about 13-14 volts. so what is the problem here?.

Richter12x2

iTrader: (1)

I'm not in favor of Optima batteries. To me that's the official - "I've got a buttload of money that I want to waste on useless things for my car" battery. Like bling for your engine bay. Your battery's cranking amps has so little to do with anything once your car's started, and with the tolerances of the electronics involved, you could almost run it on a rechargable 9-volt. Just save your money and buy some silicone radiator hoses or something.

My5ABaby

iTrader: (7)

The stock CCA were around 400.

black_88

so if the battery in it is fine and more then capable. dose any one know what chould be the problem.

unek87

i have a optima red top that puts out 920 cca . since me putting it in i have not had one problem starting it in less it was flooded. its a lil bit smaller then the battery tray but put out so much with the lil six pack design plus it only costed me $150 instead of the normal 225 plus .

Richter12x2

iTrader: (1)

If your battery is brand new and good, but only worked for a few days, my money would be on the alternator.

RDAVEX7

I also have an 88 n/a and I have had three different battery's. The first was an optima 900 cca that is now in my durango, the second was an Interstate with 625 cca that I messed up by not starting the car for a while and letting it drain down to many times, and the new one is a duralast 525 cca that is smaller than the battery tray. The duralast seems to work out just fine. A mechanic once told me that these cars need alot of cranking power from a bigger battery, but since I took out all the stereo equipment and disconnect the battery when I dont drive it for more than a day it works just fine. I got tired of buying expensive battery's when all I do is kill them or use them in another car.

black_88

ok thanks for the help. but the volt meter is saying it is charging at at 13 volts. so is it still the alternator that is bad?. or chould it mabey be the starter solenoid that is bad?.

Richter12x2

iTrader: (1)

That would be easy to tell - when you get in your car to start it, and it doesn't start, do your cabin lights still come on? If it's too bright and you can't tell, turn your headlights on. If your charging system is bad (either bad battery or low battery because the alternator's not charging it) then the lights won't come on or will be very very dim.

If the lights are fine, then just hit Start a couple of times in a row - from what I've heard and seen myself, the starter solenoid will usually free up if you hit it a couple of times in a row - for example, mine was every third time - *click* *click* *vrrrmmm*.

black_88

so I put the battery back in and I went and checked and the lights are fine. and I went to crank it over and it went and started right up. but I still dont know why the battery is being drained?.

Richter12x2

iTrader: (1)

Pull fuses - if there's something in your car that's drawing down the battery when the car is off, then you should see a pretty good spark jump when you plug the fuse in for the circuit it's on. Otherwise your alternator just isn't charging the battery. If you have an ammeter, you can put connect it across the fuse terminals after you pull the fuse and see how many amps are being pulled through that circuit.

FCKing1995

iTrader: (3)

800CCA/1000CA for $59.99 at AutoZone. Been doing well for over 6 months now. Havent had a starting issue yet

magus2222

iTrader: (22)

Richter is right, start pulling fuses and check any possible electric leaks. and btw, there is nothing wrong with optimas, people just misuse them, they are designed for higher output stereo systems. they also have side mount terminals for aftermarket systems. (im running 1500 watts (120something amps) and need a good deep cycle battery). but to just run your car, all you need is like a duralast or some offname brand for cranking the engine over. if you arent running high amp systems, dont go with optima, they are expensive.

Richter12x2

iTrader: (1)

More or less, that's what I was trying to say. If you don't have a monster audio system in your car, you don't need a $200 battery.

black_88

which fuses should I pull so I know where to start looking first. the fuse block in the engine compartment or the one by the drivers foot. or should I take the battery back and get it replaced first.

black_88

right now it still has the stock raido in it. and evary thing on it is still stock.

Richter12x2

iTrader: (1)

I'd start with the ones in the engine compartment, because the fusebox in the passenger cabin gets it's power from one of those.

black_88

are there any other fuse blocks I should test to.

JoshN9123

I work at a battery store, so I am constantly checking batteries and alternators day in and day out. We go by a few standards when checking a battery and alternator. The group size that fits in the fc's are a group 35. They are normally rated at around 550 or 600 cca. We usually recommend atleast 550 cca in anything under 32degrees for any passenger car really. You can test your alternator with a voltmeter, by placing the positive right on the hot wire to your alternator, and grounding anywhere, and with everything on (lights, radio, heat, wipers) the alternator should be putting out 13.6 or better. Also check your battery voltage and see if it is below 12.5, if it is then it's been ran down by either the alternator or a drain in the electrical system. If it's at 12.5 and the car still won't start, the battery is most likely bad.

I don't know if that helps or not, or even if thats a proven way of checking it out, but thats what we go by, and it seems to work just fine.

JoshN9123

Also, if everything looks alright, go try another battery, batteries can come bad right off the shelf, just like any other part, and could be your whole problem.