'84 Chevy RV BB 454 Alternator Repair

[Jbray]

After I have determined that my alternator is not functioning, how do I determine which part to replace? Is the stator bad very often and how do I test it?
Thank You!!

Jim

[drew]

Well, my application guide doesn't have Chevy RVs in it. You can find a model number stamped on the case, next to the output amperage. If I know the series alternator, I can direct you through troubleshooting procedures.

[Jbray]

Thanks, I will get it this afternoon. The RV is on a P-30 chassis. Will probably be the same as a 454 Suburban with AC. I appreciate the help. I stumbled onto this site last PM and I will surely pass it on!

Jim

[drew]

According to my application guide, it should have a 94 amp 12Si alternator, which is good news. If the alternator is still on the vehicle, you should check the output voltage at moderate engine speed, it should be between 14-15 volts. If not, you can test the voltage regulator by inserting a screwdriver in a special D shaped hole on the rear case, by the plug. There are a number of D shaped holes on the 12Si, but the test hole is not on the perimeter of the case and has a small tab of metal in it. Ground this tab to the case using the screwdriver and your alternator should start full fielding, bypassing the voltage regulator. Do this for only a short period of time. If you get proper voltage this way, your voltage regulator is bad. If you still don't get 14-15 volts, then you should probably remove the vehicle and go through some standard testing procedures which require the use of an ohmmeter.

[Jbray]

Thanks again.. I have not been able to get to the RV yet. It may be as late as this weekend. If it is not the 12Si I will get back with the other type.

You mentioned that it was good news if it was the 12Si. Why is this model good news?

Thanks again for the help.. I really appreciate it!

Jim

[drew]

The 12Si is really easy to take apart and repair and it can be interchanged very easily.