Hi all ive got an odd one. The alternator on my 89 3vze recently went kaput all at once. The battery still read strong 12.6v but was getting nothing from the alternator when the car was started. It has done this about twice now, Ill drive it to work and everything is fine, shut it off, try and start it soon after and will get nothing from the alternator. Come back to it after a few hours and the alternator will work fine and get me all the way home with no issues. The alternator light works just fine and i have a volt gauge that reads around 14 when its working and 12 when it isnt.

Ive cleaned the connectors to the alternator, the belt is well tensioned. Im not sure where else to look

I have no idea what can take a good strong alternator and make it suddenly seem to have hot start problems?

 

How many miles has the alternator run??

Maybe worn brushes. Not too hard to change them.

 

Its been in the truck as long as ive owned it, so 30k minimum... Would worn brushes output a strong 14 or so volts when working properly? Sorry im used to alternators dying slowly.

 

Yes, short brushes can cause intermittant no charge conditions.
Eventually leading to complete failure to charge.
No excitation, no output.

 

Gotcha, ill have it out tomorrow and will give it a check. I don't wanna get rid of my otherwise good working original toyota alternator. Know of a source to get good replacement brushes if that is the problem? It seems likely.

 

I always keep a spare set or two in my parts cabinet.

I get 'em from Ebay. $8 or $10 for the cassette.

Possible to get the internal regulators too, or even rebuild kits complete with bearings.

 

Any specific part numbers you'd care to share?

 

The number on my spare brush cassette for my 92 3vze runner is :

39-8203 and says Denso BH 2 terminal w/shield.

This number gives several Ebay results.

If you then look at the Ebay listings, some of them give interchange numbers from Toyota and quite a few others.

I am sure that with a little digging, spare parts can easily be found for just about any Denso alternator.

I am not familiar enough to rattle off the various models of units as found on different year/model trucks, but when I have had one in my hand, I've never had trouble finding the right stuff to keep them going.

I haven't had to buy many new complete alternators of any type.

Most dead alternators can be repaired for small money.

 

Cool, toyota dealership is closed tomorrow. Ill post pictures once i get it cracked open

 

Yes well that might be the case living in That dry climate of AZ .

Here in the great Brine and Rust Belt the overall corrosion tends to make things real interesting .Till the cost of replacing all the needed parts and the time involved I just buy a new alternator . Not rebuilt!!

Being in my advanced years and not in the habit of taking pictures of everything I never think of taking them.

 

Well I did the 4 dollar soldered on brush fix because I needed to get to work and Toyota was closed. Now the lights pulsate. I was gonna grab the Toyota brushes tomorrow, should I grab a regulator too? Or do I probably just have a bad soldered connection?

 

whelp now it flickers and the voltage has jumped to peg my gauge at 16 volts... seems my regulator is done.