testing your alternators

[carctruck]

Im looking through the maintenance manual on testing alternators, and Im sure everyone else has seen that a test bench is the preferred method for testing. My gen 2 light is sweeping bright to dim, and Im reading 30VDC cycling to 28VDC in sync with the light, meanwhile my voltage gauge stays motionless at the high end of green. Anyone else have this happen to them?

 

[Oldsouthernboy]

MY gen 1 did the same thing, Diodes and voltage regulater was both bad. I had a rebuild did at local shop, while i ran my spare alt 1.

 

[MrBouncer]

What was the cost on rebuilding your alternator?

 

[Oldsouthernboy]

Cost me 76.00 I got a year warrenty and a local shop to bitch to

 

[niferous]

My Gen 2 light comes on sporadically web though the alternator was rebuilt. The voltage does not drop and the alternators test good. Any ideas? It only does it at idle.

 

[DaNZaVaR]

is the gen 2 alt. on the drivers side? i am having the same problem

 

[Warthog]

My Gen 2 light comes on sporadically web though the alternator was rebuilt. The voltage does not drop and the alternators test good. Any ideas? It only does it at idle.

Just because the alternator was rebuilt doesn't mean the parts are good. I have seen new "china" parts fail before and shortly after installation.

Have it tested.

 

[niferous]

Just because the alternator was rebuilt doesn't mean the parts are good. I have seen new "china" parts fail before and shortly after installation.

Have it tested.

Have it tested at a shop or test it myself on the truck? They both put out the required power.

 

[gaunt1969]

sounds like the voltage regulator. you can get the parts for around $40 and do it yourself in less than 1hr "30 min" if u done it b-4. its very easy to do.