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TR6 TR6 ignition light faint - this can't be good

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Thanks everyone. I will pick up a meter this weekend and double check just to be sure. I fell asleep before I had a chance to read my Bentley. Is it possible to check out if an alternator is good without actually putting it in your car? I figure for a long trip it would be nice to have a few spares with me just in case.

Kevin
 
Add my voice to the chorus since you said that, Kevin.

Real starter and alternator shops will test your alternator off the car. They hook it up and spin it to the max, which you probably would not want to do installed on the engine.
Around here testing is free.
 
ichthos said:
Is it possible to check out if an alternator is good without actually putting it in your car?
Click to expand...
Yeah, but it basically involves a simulated installation. Spin it up, apply some excitation, see if it works. I built a little stand using a washing machine motor, but that's probably more than you want to tackle. Also my washing machine motor wasn't strong enough to handle full load, so I couldn't really do a complete test. It was only 1/4hp or so, and you'd need over 1hp (depending somewhat on the alternator rating) to achieve full output.

Pep Boys (a west coast auto parts/service chain) used to do the test for free, but I don't know if they still do.
 
I thought about it, and it wouldn't be that big of a deal to put my spare in and see if it works <span style="font-weight: bold"><span style="font-style: italic">in</span></span> the car. Then if it doesn't work I can do further testing. Thanks again,
Kevin
 
If you're going to DIY, be sure to check out the bearings as well as the function under full load.
 
TR3driver said:
ichthos said:
Pep Boys (a west coast auto parts/service chain) used to do the test for free, but I don't know if they still do.
Click to expand...

Actually, the first Pep Boys Store opened in 1946 in Philadelphia. Currently, Pep Boys, headquartered in the Allegheny West section of Philadelphia, has 600 stores and approximately 6,000 service bays in 35 states and Puerto Rico
:smile:
Click to expand...
 
If the shaft moves smoothly with my hand, wouldn't that mean the bearings are good? Putting the bearings under load in my car would make more sense to test them, but how would I know if they were bad unless they were so far gone that they started making noise?
Kevin
 
Ok, my mistake. Didn't remember seeing them outside of CA & AZ. Anyway, I was just trying to explain what a "Pep Boys" was.

Looks like there are even a few of them in WA, but they may not be convenient for Kevin.
 
Mine were kinda noisy, but so is an alternator when it's charging.
I followed my own advice, though and brought it to an alternator shop, where the diagnosis was made.. free of charge.
 
If bearings are the problem, then you'll either hear the racket from the bearings, or the belt squalling.

Besides, I'd say there is essentially no chance that the belt is slipping just the right amount to cause the light to glow dimly. Belt slip (due to bad bearings or whatever) can be a problem, but you'll get either no light, or full bright.
 
Worn out bearings are loud; ones not so far gone aren't quite as obvious. Maybe the shaft will be a little loose, too, if you have a good one to compare.
 
I think we're scaring Kevin.

Current one appears fine, if you have a spare that Autozone checks out to OK then I'd not worry about it and enjoy the drive!
 
I agree with that alright.
I'd trust someone who has the equipment and knows how to use it to give it a complete check-up rather than Kevin just trying it out on his car.
 
Kevin, pull it and bring to an Auto electrician in Oly. I know they have em there.

Just do the Google thing
 
ichthos said:
I thought about it, and it wouldn't be that big of a deal to put my spare in and see if it works <span style="font-weight: bold"><span style="font-style: italic">in</span></span> the car. Then if it doesn't work I can do further testing. Thanks again,
Kevin
Click to expand...

Kevin, put in the spare, that is what they are for. If the light goes out, you know it was the old alternator. If it stays on, then the problem is elsewhere.

The last time I looked for alternator bearings, only Rimmer Bros. in the UK had them.
 
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