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Toyota 22R alternator

Posted: Thu Oct 04, 2012 10:10 am
by LowandLoud
So this has been the summer of alternator issues.

My truck has been down a total of 7 weeks for alternator issues. Blew up the original,no surprise as it is only a 60amp unit. Replaced it with another original i had in the garage. That lasted about 2 weeks. Finally pulled it again to be rebuilt and hopped up(rewound) at a reputable local guys shop. Installed it only to find no current coming out at all. Apparently it passed the rebuilders bench test. Removed and returned it to the shop to find a "burned out stator"? Strange but he came good for it. Finally got it back, installed and charging. Now it seems to be overcharging as i am getting 15.3V at the alternator stud, and 15.2 at the battery with my DMM. My lights and gauges are "pulsing" continually, even with the inline fuse removed. I have just had a brand new Sylvania Silverstar headlight go out and i think it is caused by this overcharging.

My question i guess is this: Is there anything i can put inline to slightly decrease or adjust the voltage reaching the battery? I know pulling it and taking it back is what will happen at the end of the season but its almost over now and i would like to enjoy what little cruising time i have left. It is a real PITA to get this alternator out and i have already re and re'd it 3 times so far :doh: Any ideas?

LL

Re: Toyota 22R alternator

Posted: Thu Oct 04, 2012 12:55 pm
by ajaye
I'm sure someone with more expertise can give you a better answer, but it sounds like the alternator's voltage regulator isn't doing its job properly or was modified improperly. I would ask the rebuilder, but I'm pretty sure even if you add some type of voltage dividing network, if the regulator isn't functioning properly you're still going to have issues.

Re: Toyota 22R alternator

Posted: Thu Oct 04, 2012 1:55 pm
by ttocs
I know this is going to make you roll your eyes just like when the tech bench tells you to reboot your pc, but check your grounds. If the ground from the chassis to the block has corroded it would cause problems like this either burning them out from seeking a ground through sensative circuits or having no ouput. I am willing to get the day you measured 15v your meter acted as a ground, where did you attach the ground at the batter or the alts chassis? Not sure where the factory grounds are at but look for them and give them a good tug/pull/wiggle to see if they move AT ALL or just come off. At the very least clean all the connections or even better yet upgrade/add a ground to it as it will be one less thing to worry about in trouble shooting.

You could also test this by setting your meter to read current and then connecting between the chassis/block. If the ground is good then your meter should have a very low/nothing reading for current.

Re: Toyota 22R alternator

Posted: Thu Oct 04, 2012 4:30 pm
by LowandLoud
Thanks for the ideas guys.

The voltage regulator is new with the rebuild. I know that doesnt always mean its good but its a fact. One thing i did notice is that it wasnt an exact match to the old one as the ring terminal on the power wire did not line up and sit flush. I had to make a slight notch in the plastic of the regulator because there was a raised collar around the connection. I have checked/cleaned and retightened all the grounds except the one on the block. I will look for that one tomorrow. I will be replacing all of them with 0 gauge when my spools come in. When i got the 15V, I was grounding the meter to the battery for both measurements. It would rock if it was that simple and i didnt have to remove the alternator again.

Thanks again for the quick responses, this is the single most helpful website i have ever been a member of.

LL