firstRX-7

I think I may have an alternator problem, my car won't start by it self and when I boost it is just stalls when I'm driving. does that sound like an alt problem????? I also put a new battery in and nothing changed.

firstRX-7

whats the benifit of putting in a 2nd gen altenator???

riffraff

2nd gen is just a higher amp rating...

yah. that does sound like your alt could be bad. out of curiosity, have you check the belt?

firstRX-7

no I havn't checked the belt.....is it slipping maybe?

82transam

iTrader: (18)

yea that does sound like an alt problem. I would just upgrade to the 2nd gen alt. The later models, like the later 80's put out 80 amps. Plenty of power to put juice to anyhting you want. There have been numerous threads on how to do this.

firstRX-7

what do you think a used 2nd gen alt will cost me?

mar3

iTrader: (8)

Some hot dog claims he bought an '89 alt for $15 on Ebay, but most boneyards will charge $20 or so if you get it yourself. Here's the rest of the info you'll need to get the job done...

Ahhh, the '89-'91 2ndgen alt into an '80 rex thread yet again!!

Everything you need minus the alternator...kinda strange that a new battery wouldn't keep it running for at least a couple of hours before weakening. I'd check your battery cables thoroughly for good contact everywhere and make sure you've got a solid connection cable-wise from the block to the frame....why, I believe I even had a thread on that subject, too!!

The key to superior grounding and thus, never worrying about stereo alt whining....


Hope that covers all the important ground for you! Good luck, amigo!!

crankit

In reference to the above post on superior ground. It would be much easier to attach a ground cable between the engine and frame and leave the originals alone. Tell me why its not.

mar3

iTrader: (8)

The above thread was to actually benefit the starter. The superior grounding is just another benefit of the modification. It is a little out of context for this guy's problem, I'll give you that...

hanman

FirstRX,
Do your self a favor, before you do anything else. Upgrade/replace your battery cables.
Buy 4' of 2ga wire, 4' of 4ga wire, 3 4ga brass crimp ring connectors, and 1 4ga brass crimp connector. Buy two new battery post connectors, I like the "toolless" type, so you can disconnect the battery without tools in 1 second. Also buy some sort of battery preservative.
Cut the 4 ga. wire the same lengths as the stock negative cable. You will have enough left over for a spare grounding cable. Then hook the crimp connectors on both ends of one cable and on the one end of the other. Make sure to use the preservative inside these connections, or you could solder them. Then on the remaining end put the negative toolless terminal and you are done with the negative cable. The positive cable is even easier.

To give you an idea how important battery cables are..... I just bought a 85 GSL-SE with a diagnosed low compression (bad) engine. It wouldn't start without injecting oil in the rotor housings and then pull starting it. After doing the above replacement, it fires up by just barely turning the key!
The cables in our old RX's are just too old and corroded.
just my opinion,
hanman

by the way, if you are going to replace the alt. with a second gen, I advise you to upgrade the fusible links with a second gen fuse block. Again, there is a thread on this subject.

firstRX-7

ok, thanks alot guys.......I don't know how long it would have taken me to figure this out without the forum.......I love this place

82transam

iTrader: (18)

Hey Mar3 I'm that "hot dog" that claimed to get my 89 gtu 80 amp alt for $15. Don't believe me check the link. the auction is still up there.

http://cgi.ebay.com/ebaymotors/ws/eb...935734&r=0&t=0

82transam

iTrader: (18)

hanman I agree with you 100% I am upgrading my fuseable links to a second gen fuse block. I just got it from a guy so hopefully I'll do it this week. I'll let everyone know how it turns out.

mar3

iTrader: (8)

Take pics of your project and give us the real time it takes to do the job right...............................hot ddaaaawwwwgggggg........

firstRX-7

ok things keep getting worse and worse.....I charged the batterey fully using a trickle charger. and the car started but it only ran for about 30sec before it stalled out. Now, one of the above posts said that the car should still run for a while on the battery alone. It didn't. anyone else have any Idea what the problem might be????? I'm at a real loss here guys. I've had this car for about 4 days now. This is absolutly devistating!! and when I drive the car it almost feels like it is out of gas.......thats what I though the problem was at first but it's got a full tank now, and still nothing. and the car runs normal when it's hooked up to the other vehicle using jumper cables.....but as soon as I remove the cables the RPMs drop and shortly after it stalls out..which leads me to believe this is an elictrical problem.....but I cant figure it out. sorry I keep running on like this but I don't know what to do anymore.

Directfreak

iTrader: (2)

Replace the battery. After being totally drained a few times, a battery loses its potential to store energy.

If this is gonna be your daily driver...

Replace the battery AND replace the alternator, as it was probably overstrained trying to keep the amperage up with the dead battery and lost its charging capabilities.

Try swapping the battery from another car, and seeing if it runs for more than 30 secs.

If it does, then listen to my advice. Many moons ago (ok, years) my 81 GSL suffered this same fate.

mar3

iTrader: (8)

When the car stalled out, were any of your other electrical systems still going? Specifically, listen for the fuel pump in the rear after the car has stalled. Play the stereo. Hit the hazards. Does all this stuff work normally once the car has died? I'm trying to rule out an electrical problem with these questions...

82transam

iTrader: (18)

Haha mar3, knowing how lazy I am it'll take me a good month or two just to get started on it. But yea, I'lltry to take extensive "work in progress" shots for everyone as this seems to be a popular swap to do. Very easy from what everyone has told me. I plan to go overkill and use the 4ga wire I have left from when I installed my amp. I'll have virtually no resistance in my car!!!

back to the original thread; firstrx-7; it almost sounds like the electrical system is not at fault here. Sounds like either fuel or spark problem. Check to see if the plugs all have spark and that you are getting fuel into the carb. I don't think a battery, even a crappy one would run for only 30 secs. One of my lawnmowers has a shot alternator and the battery will go for months of weekend useage before it needs a recharge. Just a thought. Hope you fix the problem, these cars are fun as hell but also very frustrating sometimes, don't let this taint your view of the rx7. Peace

firstRX-7

to answer mar3's question I ran the radio and my headlights but turning them on is usually enough to stall out the car. It seems like the car needs all the power it can get just to stay moving. The only reason I think it's elictrical is that when it was on the booster cables hooked up to my friends car it ran fine.....radio lights everything, but as soon as the cables were removed the radio cut out lights faded and the engine started to run really rough......and the voltage gauge in the dash dropped as well. Would a worn out plug or wires cause this??

firstRX-7

ok and yeah I can hear the fuel pump.

firstRX-7

ok I pulled all the plugs out to check them out......the tips of them were all black and covered in dirty oil so I cleaned them a bit and tested them and they still fire..I'll probably replace them anyway, but could that be my problem?

82transam

iTrader: (18)

Well, if jumper cables make it run fine probably not. But, it might not hurt to get some cheap autolite plugs and new wires and try it out. maybe the plugs are so shot they need the extra voltage just to fire right. I can't tell ya for sure, just a guess.

mar3

iTrader: (8)

This absolutely screams "battery!" Even if it's bought brand-new, don't assume it's good. Return it no matter what the store test equipment says and get a replacement and try that.