bad starter or bad ground connection? - & activating starter from engine bay?

[onosqv]

Auto 89 240sx. Autozone Starter...

Ok, recently my starter has been acting up again - you can hear the relay click one time, the starter solenoid (or whatever it is) click loud one time, the battery voltage level dropping... but no cranking.

1st autozone starter lasted 2 years til around January of this year.Replaced it, the starter gear gets stuck and shaves itself off in the first 2 days.Got it replaced again - was fine for maybe a week or two. Then the problems came back.

The starter solenoid seems to get stuck. The way to solve it is to have to people: one starting the car, one tapping on the starter. Happens approximately once a week.

Typically seems to happen when I need to make 2 or 3 short trips, one after the other. But has also happened when I left the car sitting there one day for about 12 hours... so who knows.

I'm trying to figure out if it's the autozone starter, or my electrical connections. When I bring in the autozone starter (the original one that failed), they keep testing it, and it keeps turning out "good"...

If it is the electrical connection, where do I check? Everything seems connected ok, no corrosion (battery is in trunk - this mod was done way before any starting problems occurred).

Lastly, is it possible to hook up a switch or something to activate the starter from the engine bay? This will save me a lot of hassle so I don't need 2 ppl to start my car during the meantime til I figure out this problem... so I can tap the starter and activate it at the same time.

THANKS!

[jdm_master_X]

if it requires someone to shake the plunger to pull out, the starter is most likely defective. half the time the solenoids arent getting the correct voltage and try to scavenge for more power from the battery, which can still be insufficient.

the best way to test the starter is to remove it and bench test it with a battery and jumper cables. connect one end of the cables to the battery and another to the proper terminals on the starter. when you do this, it should spin up on its own. try this a couple of times and see if it can do it by itself. also, if u have a voltmeter on hand, place it own the battery and see how much voltage is being drawn to the starter. if its too high, get a new starter.

[onosqv]

Happen to remember which terminals are the correct one on the starter? I have a multimeter, just need to buy a new battery for it.

The big wire to the starter = 12v or ground?Small wire = opposite rite?

The battery level (measured @ the ecu bcs I have a safc) is about 11.7-11.9 depending on how long it's been since I drove the car.

Starting the car, battery level will go down to 10.8-11, depending on how long I crank.

[benemorius]

First take care of the battery. Those numbers are hideously low. If that doesn't fix it then it's probably that cursed autozone starter. Just because it tests good doesn't mean it will work consistantly in the real world. If you wish to test it, the positive terminal is the outermost bolt on the solenoid; the negative is any good connection on the metal housing; the signal wire is the small wire coming off of it.

[onosqv]

What voltage is it suppose to be while cranking the car?

[benemorius]

It depends on the strength of the battery so it varies quite a bit. With no load it should be at least 12.5, though, and seeing as how the starter isn't actually turning there should be NO significant drop when you turn the key.

[onosqv]

Well, I'm not sure, every car I've ever multimetered (which isn't that many, but still) was always around 12v when car is off...

From what I figured, power is getting to the starter, and the starter is trying to turn, but the solenoid is stuck.

I figured if the battery is bad, wouldn't there be more consistent problems?

The smaller wire is the signal wire - ok, I have an idea . Anyone know off the top of their head if it's a 12v signal or ground signal?

I think this will allow me to do my temp solution to starting my car when I'm alone in the middle of the night and the starter gets stuck.

[benemorius]

It's 12v signal, as I recall.

12v is too low, and 11.7v is stupidly low. At the very least you really should temporarily borrow a good battery while you finish diagnosing the problem. Everything you have experienced so far can be caused by a weak battery. You need to be sure that the battery is not the sole cause everything.

[onosqv]

I'll do just that, thanks.

I'll swap the battery w/ my other car.

[onosqv]

O, and I'm not sure if it matters or not. But the battery is a dry-cell, which they claim will have starting power even when voltage is low. Good to the last drop