Is my bendix toast?

[andy.262]

so the starter on my 97 SPX is having some issues, and I suspect the bendix. When I hit the start button it sometimes engages and starts the engine, but usually just makes a whirring noise and doesn't crank the engine. My guess was that the whirring noise was the starter motor spinning but not engaging with the flywheel. So I took out the starter to examine the bendix, and this is what I found. I have no experience with starter motors so I'm actually not sure if this looks good or not. In my head it makes total sense that this would be the thing that's broken, but visually to me it looks like it might be OK. What do you guys think, is my bendix toast or not toast?

 

[AKnarrowback]

CLEAN EVERYTHING.

The bendix gear should only turn in one direction, if it spins in the housing in both directions replace it.

The rust evidence is a concern.

One, it could be stopping the internals from working properly.

Two, there shouldn't be any water getting into that part of the motor to cause rust in the first place.

Make sure you use some fresh grease on the starter shaft, the battery is charged and give things a try.

There is a chance, based on the rust evidence, that there would be water damage inside the starter. If the starter isn't spinning fast enough due to water damage then it won't operate as designed.

Clean things up.
Grease things up.
Seal things up (water).
Charge things up (battery).
Give things a start and tell us what you see.

 

[andy.262]

I will clean and grease it as you say, and give it a go. The previous owner didn't take the best care of it so I'm not surprised it's got a little rust. A few seasons ago I rebuilt the engine so hopefully whatever was allowing moisture in there was sealed up during the rebuild.

 

[AKnarrowback]

A USED OEM starter with new brushes installed is better than a brand new aftermarket starter any day.

 

[andy.262]

That's a good idea, I should get some new brushes in there while I have it out anyways. I already have to order a new snap ring for the bendix since I had to cut the original one off, so I'll add some new brushes to that order too I guess

 

[andy.262]

Ok so now I'm really frustrated with this thing. First of all that stupid circlip that holds the bendix spring is impossible to work with. Second, even after rebuilding the starter motor with new brushes and cleaning and greasing up the bendix, it still does that whirring thing. I posted a short video clip on YouTube at the link above so you can see what I mean. The starter definitely sounds and spins stronger than before the rebuild, but I don't think it's engaging every time still.

 

[POPPS]

Its possible,,,that you have burned out windings,,,do a draw test.

 

[andy.262]

so that test goes like: place a multimeter over the battery (or starter?) terminals and then crank the engine and see what the voltage drop is?

what would be considered a "bad" voltage drop?

 

[andy.262]

so testing the voltage like I said above, tester leads on the battery, it drops 1-2 volts (down to 10-11 volts total) when the starter is spinning. I'm not really sure if that's good or not