FJ62 Electrical Demons

[Ming89FJ62]

Ok, this is probably the 4th or 5th alternator in our FJ62. Installed a Toyota reman about 4 months ago to replace the one that died. At idle w/ the head lights, radio, heater etc. on I'm barely at 12v on the voltage gauge. If I use the directionals i dip even lower into the 10v range. I've replaced all the battery cables, the fusible links (just this last weekend), and even replaced the ring connector on the alternator that leads back to the battery to make sure that the connection is sound. Am I stuck with this - or should I replace the alternator w/ a GM that has higher output at low RPM.

Ming

 

[Mike S]

You can have your existing alternator rebuilt and rewound to produce over 100 amps - cheaper than a new GM with brackets. etc. and stock. Just about any gen/alt shop can do this. My shop says that they can rewind my stock 2F alternator to give me 120 Amps at hiway speed and as much as 90 Amps at idle.

Call your local guy and ask him what he an do.

 

[Ming89FJ62]

Tried the upgrade/rewind at a local shop. Apparently the alternator for the 3FE is not an easy candidate for upgrading. The only alternate from the OEM alternator that I'm aware of is either a GM or Mean Green and I really don't want to drop $300+ for a Mean Green if it won't solve the low RPM out-put problem. Does anyone elses 62 have the same problem at idle? I know that the truck is 15 years old and that there could be some oxidation in the connectors of the wiring harness but this is driving me nuts. Is there a different I/C voltage regulator?

Ming

 

[jwest]

I would make sure you have good clean connections.
Clean battery posts... simple sand paper will do this. Then clean and check all your grounds, both at the block and the body.

Yes, 12v at idle is too low, even under load. But, I'm not sure why you'd need to deviate from standard unless your power requirements call for it. If the alt's bad, take it back ...isn't it under warranty? They'll bench test it.

 

[Rollin'in'Zona]

62 volt meter

I know this is an old post, but...

Have you tested the actual output on a volt meter under the hood? I had this problem, after replacing alternators, on both a 60 and 62, and both times the voltage was fine!

So in my case, the issue was either 1) the guage was off, or 2) there was a loss of juice in the wiring to the guage.

I just re-calibrated the guage in the 60 and all was good!

The 62 has two Optima batteries and Mean Green isolator. The islator will rob about a volt.
When everything is on (wipers, highbeams, stereo, GPS, CB, ham) the volt meter in the truck dopr to about 11, BUT, under the hood, it reads 16+.

Go figure.

Ok, this is probably the 4th or 5th alternator in our FJ62. Installed a Toyota reman about 4 months ago to replace the one that died. At idle w/ the head lights, radio, heater etc. on I'm barely at 12v on the voltage gauge. If I use the directionals i dip even lower into the 10v range. I've replaced all the battery cables, the fusible links (just this last weekend), and even replaced the ring connector on the alternator that leads back to the battery to make sure that the connection is sound. Am I stuck with this - or should I replace the alternator w/ a GM that has higher output at low RPM.

Ming

 

[Doc]

I don't know if it matters, or if you care- but my 87 fj60 runs at about 11.7v at idle. It's never been a problem. Everytime I have someone test my battery or alternator they say I need a new alternator, low output. So I bought a brand new alternator. Installed it, and guess what? Low output.

So I measured the output with a handheld meter and it was the same as the old one. Put the original alternator back in and took the new one back for a refund.

It's never left me stranded, or failed to crank the engine. So I don't worry about it.

 

[dd113]

I know this is an old post, but...

Have you tested the actual output on a volt meter under the hood? I had this problem, after replacing alternators, on both a 60 and 62, and both times the voltage was fine!

So in my case, the issue was either 1) the guage was off, or 2) there was a loss of juice in the wiring to the guage.

I just re-calibrated the guage in the 60 and all was good!

The 62 has two Optima batteries and Mean Green isolator. The islator will rob about a volt.
When everything is on (wipers, highbeams, stereo, GPS, CB, ham) the volt meter in the truck dopr to about 11, BUT, under the hood, it reads 16+.

Go figure.

Exactly! meter at the B+ terminal on the alt with no load and full load. Rev the motor a bit when you go to full load then let it go back to idle. Do the same thing at the battery. Reading should match within 1/2 a V or so.

Re do the main connector on the harness going to the + terminal as it usually is bad, the + line from the alt to the bat has the nut connection just after the batt and corrodes. Re do that into a single wire connection.

 

[swank60]

Okay, so it's an old post but, for the sake of it all: is it the right pulley size? I got a rebuilt alt a year or more ago and it had the wrong pulley on it - the diameter was okay for mine, but the width was warong and wouldn't take the correct belt. If the diameter is too small, or the belt is wrong, you could have low output at idle.