Do I Have to Replace the Rectifier & the Stator?

If a stator goes bad and needs to be replaced, does that mean the regulator-rectifier has to be replaced as well? It’s a more common question than you might think.

John Talley does weekly live Q&A sessions every Friday at 3PM Eastern on our YouTube channel. In this session, several electrical system questions came up, especially related to stators. Here’s what John had to say about a viewer’s question on whether a regulator-rectifier needs to be replaced along with the stator.

Stator testing

Testing Stators and Regulator-Rectifiers

If I have to replace the stator, do I have to replace the rectifier as well? I hear you have to replace both at the same time. Is this true?

John Talley: If you want to be absolutely sure, well I don’t know. I’ve said this many times, nine times out of 10 it’s just going to be the regulator-rectifier. That’s just the way it is. The stator itself is very, very seldom the problem unless it’s just being overtaxed to where it actually breaks down and causes an open or a short in the windings. Because it’s basically just a big coil with a magnetic field being generated, which generates electricity. But they typically don’t fail unless there’s just way too much of a draw on them and they overheat, hence either breaking connection or making a connection where it shouldn’t be. And there are ways you can test that, and we’ve gone through several videos, including a standalone video for how to test a regulator-rectifier just using a volt-ohm meter. If you see an extreme where you have a really low resistance rate or it’s completely open, well then you know you need to do something about it. If your machine’s still running, you could do a static test to see. If you’re reading somewhere in between 25 and 50 volts AC, well then you know it’s ok, and it’s just going to be the regulator-rectifier. But as far as testing the rectifier, that’s easily done as well, and we have several videos that can walk you through how to do that.