Alternator coil question

Topic: Alternator coil question (Read 3191 times) previous topic - next topic

Alternator coil question

October 22, 2007, 07:11:29 PM

I found I have a bad alt since its been sitting for almost 3 years in the garage. what usually goes bad on an alt from sitting? the coil brushes or something else? I see they cost 150 bux for a whole new alt and thats too much money for me. I found a coil off ebay for possibly 10 bux.

Alternator coil question

Reply #1 – October 23, 2007, 03:04:37 PM

How are you testing the alternator to know it is bad?
Does it have an internal regulator?
Can you post the link to e-bay so we can see what "coil" you are talking about?

Alternator coil question

Reply #2 – October 23, 2007, 04:49:14 PM

If the car's been sitting there are a few things that could go wrong with the alternator. Most common would be bearings seizing up and brushes sticking in their holders, but you can also run into moisture getting into the windings, causing them to expand, which breaks the insulation and causes shorts. Since yours has been sitting in a garage this is unlikely. I'd check the brushes.

Alternator coil question

Reply #3 – October 23, 2007, 08:43:13 PM

I think it has to be the alt because I`m getting suck a weak spark and I have gone through the whole ignition system except the coil but I ran a spark tester on the coil and got a strong spark from it. everytime I hook the tester to the distributor I get a really dim spark. The alt pulley came off before and it wouldnt pull enough power through and shows the same signs.

Alternator coil question

Reply #4 – October 23, 2007, 08:51:07 PM

If there's enough juice in the battery to spin the starter, there's enough juice to fire up the coil. Hell, I had an alternator fail in my old '85 and tried to drive it home anyway - home was 100 miles away and it was dark and raining. I had given up on headlights and wipers (thankfully the rain stopped), and was following another car. It got to the point that there wasn't even enough juice in the battery to power the digital dash or clock, but the engine kept running. I made it about 75 miles. I would have made it even further but I got pulled over by the police for driving without my headlights off, and the cop told me to shut the car off. As soon as I did I knew it wouldn't start again...

Alternator coil question

Reply #5 – October 23, 2007, 09:39:50 PM

see it ran last spring and almost started like a week ago and it was trying to start but wouldnt do nothing now.

Alternator coil question

Reply #6 – October 23, 2007, 09:44:39 PM

Does the car start?

Alternator coil question

Reply #7 – October 23, 2007, 09:47:25 PM

You answered my question before I could ask it.

The alternator doesn't do anything until the engine is running.

Alternator coil question

Reply #8 – October 23, 2007, 10:08:06 PM

Pull the codes.
Check the fuel pressure.
How does the spark look while cranking?

I am not familiar with the spark tester. How does it work?

Alternator coil question

Reply #9 – October 24, 2007, 01:05:13 AM

the spark testers just plug in to the plug wire and gator clip to ground. They substituted for a spark plug in a way.

im not really sure what this problem is here but a weak spark should be dizzy related with the tfi or the pick up/stator assembly.

Alternator coil question

Reply #10 – October 24, 2007, 01:51:48 AM

whats a pick up strator assembly? or a tfi? Is the pick up the orange looking thing inside the distributor? every time I check the obd codes it says cyl 1 and 6 problem.

Alternator coil question

Reply #11 – October 24, 2007, 10:55:50 AM

What year and engine do we have here? Is it stock?

Alternator coil question

Reply #12 – October 24, 2007, 01:00:34 PM

Its an 88 5.0 from a thunderbird sport. No matter what I do I get a weak spark. Its pretty much all stock.

Alternator coil question

Reply #13 – October 24, 2007, 08:29:30 PM

It looks like worn out brushes in the alt

Alternator coil question

Reply #14 – October 24, 2007, 08:45:19 PM

Are you not listening?? The alternator has [COLOR="Red"]NOTHING [/COLOR]to do with the car starting or not starting.

How about checking your battery cables?