Wonderful news... *pbbththt* Alternator and starter

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Bookworm
Posts: 764
Joined: Fri Nov 05, 2010 11:21 am
Location: Houston, TX

Wonderful news... *pbbththt* Alternator and starter

Post by Bookworm »

My starter was starting to occasionally spin the bendix gear, especially when cold. Today, the car wouldn't start. After pulling the negative terminal clamp, cleaning a bit (soda to remove the buildup, and scraping), and putting it back on, I was able to start it up and drive home.

Battery voltage, 12.59 volts, reasonably nominal.

Problem - After pulling clamps, cleaning (vinegar and wire brush), and remounting - everything _seemed_ right, until I turned the key. Click.

Voltage on battery sagging like crazy. Started rapping the starter, with my wife turning the key, and it started.

Problem - with low RPM, the voltage of the alternator .... wasn't there. The battery basically just showed the battery voltage. Rev the engine, and the voltage went up to 14.1, but you had to hold up the RPMs. Let it idle, and the voltage drops to next to nothing.

Classic signs of alternator failure. (I doubt any of my grounds are bad; no other signs)

So I just picked up a replacement starter AND alternator. Not looking forward to it, but I have to replace them ASAP. Luckily, I can use my wife's car for a couple of days, but I'm going to try to replace them tomorrow. It's a bit dark to do it right now unless desperate.

Edit - At 178k miles, I'm not surprised at the starter, but I am surprised about the alternator.
Bookworm
Posts: 764
Joined: Fri Nov 05, 2010 11:21 am
Location: Houston, TX

Re: Wonderful news... *pbbththt* Alternator and starter

Post by Bookworm »

Adding another thing.

Hooked up battery charger on 2 amp, just to give the battery a good solid charge, then went out to buy alternator and starter - and had dinner.

Came back home, 90 minutes or so later.

Car started easily. Scratched head.

Checked voltage - 14+ volts.

Waited 2 minutes.

Voltage dropped to 12.56 (the battery voltage, basically) and started downward.

Now I have a P2111 code as well. So I guess I'll be cleaning the throttle body as well as replacing the alternator, and probably the starter as well. (Even if it's not the starter, the bendix gear was whirring off and on, so I know it's heading south)
Bookworm
Posts: 764
Joined: Fri Nov 05, 2010 11:21 am
Location: Houston, TX

Re: Wonderful news... *pbbththt* Alternator and starter

Post by Bookworm »

Not certain about the alternator as of yet.

Autozone said that the battery was toasted just from the swollen outsides (2.5 years old, but Houston heat, stored in the sun), and I got a slightly pro-rated replacement. Still no starting, and weird voltages.

Pulled and replace the starter. Car now starts, idle is FUBAR. 500 RPM, which is nuts compared to before. I figure that 20 minutes of freeway driving may help that. (Need to replace the starter solenoid switch clip - the retainer broke when pushing gently)

Replaced the electric radiator fan - it had been off and on rattling and grinding against something, so I bought a replacement a year+ ago, and never actually put it in :) (Mostly because the rattling stopped). Since I pulled the old one to make it easier to reach the starter, I replaced it.

So, I'm still not happy that at normal idle, it's 13.3-14.1 volt, but at the low idle, it drops all the way to 12.39 volts. No alternating current apparent coming out of the alternator. Ground for the car looks good.
zbyers
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Joined: Thu Apr 03, 2014 6:12 pm
Location: Sheffield, Pennsylvania

Re: Wonderful news... *pbbththt* Alternator and starter

Post by zbyers »

Sounds like it likely could be the alternator if it's dropping to ~12.39 volts at idle.
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Bookworm
Posts: 764
Joined: Fri Nov 05, 2010 11:21 am
Location: Houston, TX

Re: Wonderful news... *pbbththt* Alternator and starter

Post by Bookworm »

The starter was definitely a problem.

I'm going to get my wife to help me test the voltage at high RPM. The 500 RPM voltage is either the same or lower than the battery voltage, and I didn't think they were supposed to do that. If the car was idling, it should have 13 volts or so. Once the learning cycle was over, it jumped over 800 RPM, and stabilized at 13.2 volts or so. This morning, the car was idling at 1200 RPM right after start.

I'm going to give it a day or so (Plus testing voltage at, say, 3000 RPM) before dropping the alternator into the system.

I don't think I've had to replace an alternator in 20 years. They just don't fail that often.
Bookworm
Posts: 764
Joined: Fri Nov 05, 2010 11:21 am
Location: Houston, TX

Re: Wonderful news... *pbbththt* Alternator and starter

Post by Bookworm »

Okay - after driving it all day, I had my wife come out. Immediately after starting engine, voltage was 13.56. After running RPM up to 3000 or so, voltage was at 13.71. This is with a fully charged new battery.

I'm going to assume that the alternator may be fine, but I'll drive it a few more days before returning the alternator.
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