FJ62 Alternator

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Cruiserdrew

Cruiserdrew

On the way there
Joined
Mar 15, 2003
Threads
219
Messages
15,839
Location
Sacramento, CA
Not really tech or a question, but my alternator went bad yesterday. The failure mode was interesting and that's why I'm posting.

Driving down the freeway going flyfishing. It was early so lights were on and so was the Defroster/AC. I noticed that the normal running voltage was at the lowest white bar, where as for the last 2 years, it's been significantly up from that.

About 10 minutes later, the battery light, the brake light and the AT temp light all came on. I shut off all the loads, exited the freeway and as I pulled off everything went back to normal. I turned the loads back on and things remained normal. Strange.

Over the next 20 miles the charging was 90% normal, with short periods of battery light and lower voltage. Stopped at a Napa store in a small town east of Lodi, battery checked out good and the alternator charging voltage was normal. Since it was only another 20 miles or so and I have 100 mile towing we went for it and drove to the stream. Fishing was crappy-3 rainbows by 2pm. Still an absolutely beautiful day on the water.

Started the truck, charging was normal and remained that way the entire drive home-90 miles. Had almost enough daylight to get the alternator out. Holy shiite that is a tough job in a 62. I ended up pulling the smog pump to get exposure. Even then it sucks and you have to pull all the brackets and pivots. Got it to the Electrical shop just as they were closing.

At the auto electric shop-they were absolutely great. Put the alternator on the spinner thing-looks like it was made in the 50s. The output comes out on an oscilloscope and by the pattern you can tell what's wrong. Very cool and way better than the mystery box they use at Napa. The rectifier was bad-one of the diodes had failed.

It was ready to pick up at 1pm today. The tech rebuilt the alternator-new bearings, new voltage reg, new brushes, cleaned it up, painted it--it looks brand new. The reg was OEM Toyota. All for $110. Reinstalled. What a massive pain and the FSM is not very good. Even tensioning the belts in a 62 is hard and you need to spend some time to puzzle out the logic. Anyway, it's working great and I can tell it puts out more power at idle-the voltage does not dip at all even with the lights and blower on.

So now the tech. I asked the rebuilder tech to spin the rebuilt unit. It puts out 86 amps! That is actually better than the rating, and it's a completely stock alternator. You could also see immediately the difference in the oscillscope tracing. He had high praise for the unit itself-thought is was well constructed from the factory.

So when your alternator goes bad, do not turn it in and get a generic rebuild from the parts chain. Instead, go to your local rebuilder and you will learn something, and likely get a superior product over a production rebuilt unit, and it isn't even very expensive.

If you are local to Sacramento, these are the guys: Lehr Auto Electric. They have been in business locally for 50 years and are top notch. The guy there that rebuilds the starters and Alternators is a good dude and very helpful/talkative.
 
The question I have is why did the diode and voltage regulator go bad? Is there a better answer than it's a 20 year old truck?
 
Nice,
Thanks for posting Drew.

I was quoted much more for a rebuild here in SF. I'm going to keep your Sacramento people in mind.
 
Randy88FJ62 said:
The question I have is why did the diode and voltage regulator go bad? Is there a better answer than it's a 20 year old truck?
Click to expand...

I think they just do. This one was original to the truck and last year it had a hard life-my son left the lights on 4-5 times and discharged the battery to zero. I understand that this can be hard on the alternator when it restarts. Don't otherwise know. It had 127k miles.
 
There's a very good auto electric shop here that I go through as well. They rebuilt my 120A Beck/Arnley unit when it went bad (same thing, rectifier took a dump), and have guys that really dig deep into parts catalogs to trace parts or find a particular non-stock part you might be looking for. I found (story in another thread I posted a while back) a Nippondenso voltage regulator that matches the off-brand one originally used in my B/A alt, so when the original VR went out I replaced it just a couple weeks ago with the ND unit and it charges beautifully. When it comes to electronic components, ND is simply better quality.

Anyway, if it weren't for these guys I wouldn't have been able to get my hands on the ND regulator as quick as I was able to. 'Nother name to throw out for the Inland Northwest guys: Toby's Battery & Auto Electric, LLC in Spokane, WA. Jason is the guy I always talk to when I go in.

I say with as cryptic as our electrical systems can be sometimes, we keep this going and post other auto electric shops that guys have had good dealings with.

edit: Andrew, you're exactly right. Using the alternator to charge the battery when it's been drained not only shortens the life of the battery, but dramatically shortens the life of the alternator and can toast a VR in one shot (been there, done that). Best thing you can do when the battery is killed like that is to put it on a 2A charger and just let it trickle charge overnight. That not only minimizes the wear & tear on the battery, but helps avoid damaging your alternator as well. I use a good quality Craftsman one that wasn't cheap, but gives great piece of mind to have around when I do need it.
 
Spook50 said:
...I say with as cryptic as our electrical systems can be sometimes, we keep this going and post other auto electric shops that guys have had good dealings with...
Click to expand...

I agree:clap:
"We have one here in Tampa, Elmer Dykes Auto-Electric. Havn't had the chance to use thm on the FJ62 yet (will soon however:frown:) , hut I have used them many times in the past.

Try having an electrical gremlin on an old Ford Tarus SHO:eek:

They found and fixed it, quickly and very reasonably.

I'll post back here when I have them diagnose the LC.
 
Do any high output "bolt on" units exist to buy?

Today on the way home it was raining. I had the wipers on, headlights/park lights and with the turn signal on the voltage would dip to about 10-11 volts every time the turn signal blinked.

Kind of 5hitty if you ask me
 
NYC FJ62 said:
Do any high output "bolt on" units exist to buy?

Today on the way home it was raining. I had the wipers on, headlights/park lights and with the turn signal on the voltage would dip to about 10-11 volts every time the turn signal blinked.

Kind of 5hitty if you ask me
Click to expand...

If you need high output and don't want to go custom I would suggest getting the coils rewound...
 
Randy88FJ62 said:
If you need high output and don't want to go custom I would suggest getting the coils rewound...
Click to expand...

You know, I asked the guy about rewinding for higher output. He discouraged that, since it makes the diodes in the rectifier work harder and run hotter. He said he could do itt, but clearly did not want to. If you want a higher output unit, just run a bigger GM alternator. There is a great thread about a 140 amp GM alternator that almost bolts up.
 
NYC FJ62 said:
Do any high output "bolt on" units exist to buy?

Today on the way home it was raining. I had the wipers on, headlights/park lights and with the turn signal on the voltage would dip to about 10-11 volts every time the turn signal blinked.

Kind of 5hitty if you ask me
Click to expand...

There is a Beck/Arnley 120A unit that's bolt-in. P/N 1860449 available from Rockauto for $180 (including core charge). You won't get rid of the dipping voltmeter when the turn signal is on though. It's just the nature of the beast.

I'd recommend making an extra charge wire to augment the factory one though. I used 1ga welding cable from the B terminal to the battery's positive terminal.
 
Try Mean Green alts. But bring your wallet, they are double that Beck/Arnley unit noted above.
 
I totally agree that if there is a good electric shop in your area, it is better to get yours rebuilt than get an off-the-shelf cheapo rebuild from the parts store. You'll get a better product, have someone who can answer questions, etc. I think this is the way to go if you want to keep the stock alternator.

I know I've preached about alternators before, but once again won't hurt. Just as Andrew's electric guy said, rebuilding for higher output is a bad idea. Not only aren't the parts up for it, but even a bigger problem is that the cooling of the unit is not up for it. Heat is a real killer. More amps = more heat. Alternators are designed for a certain amp rating and the cooling is designed for that amount of heat. If you increase the amps out, there is insufficient cooling and the alternator will run hot. That really shortens the life of an alternator. Additionally, an alternator's output varies with heat. As they heat up, their output goes down. So remember, that 140 amp alternator only puts that out when cold. Some high-end alternators (often used in ambulances) will actually have an external rectifier (diodes). This moves the item that generates the majority of heat out of the alternator so that the output can remain towards the maximum since the alternator will be running cooler and enables various cooling solutions (fans, placement in front of radiator) of the rectifier.

If a larger alternator is in your plans, check out Leece Neville alternators. And I do mean a larger alternator. They are quite big and super heavy duty. You'll have to fab the bracket, but that is basically it. The one's I've used have nothing to hook up but battery plus and ground. Designed for big rigs, motor homes, ambulances, etc. Easy to find and service. These are popular with the mobile high power people who run insane CB radio and also car stereo setups. I've run one for years and my radio buddies will run 3 or more! Good stuff. Considerably cheaper than a mean-green setup (I've never paid more than $150 for a 200 amp unit), but does require some work on your part. As always, JMHO.
 
Wow, Cruiserdrew, I wish you had posted this two days earlier, when I replaced my alternator. I was literally getting your exact same symptoms. I went with a rebuilt alternator from O'Rielly's. Got a lifetime gaurantee, so hope it does the trick, and yes that was the most difficult alternator I have ever removed in my life, I had to remove the smog pump, and the brackets. Of course as i was putting the smog pump back on, I caracked the check valve. so had to order a new one, next day there it was and now she runs like a champ.
 
I don't know if they are still available, but I bought a rebuilt Toyo alternator from the dealership when mine failed a long time ago. Much more than $110 though.
 
Same exact symptoms, I changed mine on thanksgiving.. I wasn't very greatful at the time, took me out of the thankful spirit. Hardest Alt i have ever changed. Have done a vette, a jeep, and a 66 stang. Took me and a buddy about 4 hours to get it put on. I too just went with the the replacement, I had to get that baby on the road, drove to dallas right after we got it in, and she rolled perfect the whole way. Now I just have to get that main seal leak fixed.
 
My '62 stumbled on Sunday. Brake light came on, charging system light came on, and the charging needle dropped to well below it's normal position. I stopped at Toyrod's place, which happened to be right near by. He stuck a meter on it, and he said it looked to him like a bad alternator. Later, I inadvertently compounded the problem by leaving the headlights on for an hour in the zero degree cold. Later still, when I turned the key, nothing, zip, zilch, nada, she was dead.

Happily, I have AAA+ which has the extended towing; 100 miles. Unhappily, I was 130 miles from home! I had to pay the difference, which turned out to be $90. Ouch!

At the moment, she's sitting in the garage. I'm gonna pull the alternator tonight and run it to the electric shop tomorrow and see what they think.

Funny how the symptoms are all similar. I never looked to see if the ATF idiot lights were on.
 
Dang...that's quite an epidemic of alternators!

It's just like a few weeks ago there was discussion of blown galley plugs in the head and mine went while that thread was still on the first page. Unbelievable.
 
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