Altenator Problem

[sneatherlin]

I have just bought my first Nissan Infiniti. A 1992 Q45 V8. The guy I bought it from said the Alternator needs replacing due to going through two new batteries. The battery after being charged will be totally drained the next day. I am unemployed/laid off and had to work off the cost of the car (landlord helped) working for him. That being said is to point out money isn't exactly flowing atm. I love the look of this car though and really want to try and get it running again. I plan on buying books on the car and continue researching it on the web so any sites and or book recommendations would be appreciated. Back to my original question, any advice/help on replacing the alternator on this car is desperately needed. I am also a mechanical newbie to let you know at what level you will be talking too. There are other issues but will put in separate posts in case they need to fall under different categories. Thank you in advance for your help.

[elwesso]

Welcome to NICO!! Sorry to hear about your work situation, but hopefully the Q will work for you..

I hate to break it to you, but the alternator on a Q isnt really something you want to cheap out on. Its not exactly an easy thing to replace (maybe 3-5 hours to replace), and almost always cheap rebuilds result in repeat performances. Your best bet would probably be to find a good used OEM one or go for a new OEM one (expensive but worth it)..

Do you have any history on the chain guides? how is the transmission?

[sneatherlin]

Thank you for such a quick reply elwesso.

Due to a possible problem with freeze plugs ( car getting hot and fluid leaking around the transmission ) I haven't driven it yet so not totally sure about the transmission. I have found a yard with a 90, 91 and 93 Q45 that they said the Alternator is compatible with. Price on one of those is $65 bucks hopefully they have already pulled. Would that classify as OEM? I am worried about doing it myself somewhat because one site I had read that you have to pull the Air Compressor. I sure hope that isn't the case. I am thinking to try and get the car continuously running to move on to other issues. I don't know anything about the Chain Guides. My wife is already eyeballing reselling it and getting my $400 back. I am hoping that doesn't happen because I can really see myself in this car going down the highway. It just has class.

[OwnerCS]

The alternator on mine was working fine. When I had the belts off for another reason, I gave the pulley a spin to hear the sound of dry bearings. I know those dry bearings would not be lasting too much longer as I replaced the alternator with a Nissan re-manufactured OEM version. Back then it cost $270 + $70 core charge. I kept the old alternator so I can have the bearings replaced and keep it as a spare. I recently checked the price and I can get one (OEM rebuilt) for $286,46 with no mention of a core charge. I might have paid too much but I have it anyway. Replacing the alternator is one of the hardest jobs I've done to the car. I think I can do a timing chain job with less effort than an alternator job.

Here's a slide show about replacing an alternator.

Once you start the show, you can sit back and just let it run.

http://s286.photobucket.com/albums/ll11 ... =slideshow

Craig

[sneatherlin]

Thank You OwnerCS,

Watched the slideshow and fascinated to look at all the pictures. The white one looks almost identical to mine, mine just not being in as good as shape as yours is. On the Valve Cover picture what is the little box attached to the Valve cover? The previous owner has those off and loose. My landlord thought maybe the brain for the coil packs.

[Skibane]

The guy I bought it from said the Alternator needs replacing due to going through two new batteries. The battery after being charged will be totally drained the next day.

Are you absolutely certain that your alternator is the problem? Have you had it load-tested, or measured the battery voltage when the engine is running?

The reason I ask is that there are other problems which can drain the battery over night, even if the alternator is working normally - For example, stuck relay contacts are notorious for doing this.

[kevindanielk]

Thank You OwnerCS,
On the Valve Cover picture what is the little box attached to the Valve cover? The previous owner has those off and loose. My landlord thought maybe the brain for the coil packs.

Those little boxes are the ignitors for the coils.

[sneatherlin]

Truthfully no, not sure about the alternator was just an assumption that was given to me by the previous owner. How would I narrow it down to one of those other things?

[Lokim]

Check the voltage while the car is running. If you're charging properly you should be getting anywhere between 13.7-14.5 volts. Take the car down to your local auto parts store and have them do a battery test, charging system test, and starter test. These should all be free and will only take a few minutes. Let us know what they find and we'll tell you where to go from there.

[sneatherlin]

Will do this weekend Lokim thank you :-)

[ThatsMyQ2Go]

OK Time to bring an old thread back...I too am having this problem with over night drain on my battery. My ABS light came on so I put two and two together and decided to pull the fuse on my ABS (30 amp block style fuse in engine bay). It held fine for several weeks. Now that I have my Q back from the stealership (seatbelt replacement) I am draining my battery again over night. I took the Q to AAP and they did a charging system test...all is good. My question is where do I go from here??

[Skibane]

Pull the positive cable off the battery post (with the engine not running), connect a DMM between the cable and post, and measure the current flowing through the connection as you start unplugging fuses and relays. When the current drops to zero as soon as you pull one particular fuse or relay, you've found the source of the problem.

A little faster technique is to pull half the fuses and relays all at once, and then see if the current drain is still there. If so, pull half of the remaining fuses and relays, and check again. Repeat until you narrow it down to one fuse or relay.

If you don't have a DMM, seriously consider getting one. They're available for dirt cheap (Harbor Freight often sells them for under 4 bucks). Once you buy one, it'll pay for itself many times over - can be used for fixing many electrical problems in the car and house.