Starting Delay - Seems to be Starter/Generator Related

[Springbok]

My 1987 gas cart has had a sporadic 1-2 second delay for a couple of years now and I've just lived with it and not really dug in to try and fix it. Well now over the past week it's gotten worse. When I hit the gas now, the starter/generator jumps initially, seems to get power right away...but it doesn't start actually spinning right away, and when it does, it starts out very slow and then catches and starts spinning. Once I'm up and running there's no issue. Because of the slow spinning I thought it was the battery (I had put the voltmeter on the battery while running and was still getting 14V+). The battery was over 7 years old so it's probably good that I replaced it, but the new battery hasn't changed the slow-spin, slow-to-start-running issue. Will replacing the brushes in the starter/gen help this issue? Any ideas? I've not ever opened up one of these starter/generators before.

[Springbok]

My motor is doing almost exactly what this motor is doing at around 0:44 seconds:

https://www.youtube.com/watch?v=u448t_MW7gE

I'm guessing I have a flat spot in the armature and should just replace the starter/gen, which is what the guy in the video is doing to the one he's working on.

[Cartmaster]

I have no idea what a set of brushes cost in your neck of the woods, but i have always managed to save these starter / generators with a new set and cleaning the armature. In the UK, its a costly job replacing with a new motor.

I love the classic statement in the video,

I cant seem to find my short 10mm socket.

I believe that all short 10mm sockets are programmed to disappear when you really need them as are the 13mm.

[Springbok]

New brushes are pretty cheap here. I'm pulling the starter/generator off today to inspect them.

Yeah my 10mm socket is always managing to hide out in my tool box too.

[Springbok]

I pulled the starter/generator out, and the brushes are in good shape and have plenty of life left. Commutator doesn't look burned or anything like that. The s/g was full of black carbon dust. I blew it all out with compressed air, cleaned up all the connections with a wire wheel, and re-assembled. We've been driving the cart around for about 2-3 hours today. The cart still has a small 1-second delay occasionally (which is what it's had for the past few years), but the slow crank and long delays I was experiencing over the past week seem to be gone.

[CP241]

I was just going to say check the connections, particularly the grounds for dirt and corrosion. That made a huge difference on my carryall

[Springbok]

Been over a month now and the cart is still running and starting very well.

[Cartmaster]

Good to know, it would pay to blow out the carbon dust a couple of times a year anyway. Less if not used regularly.

[Springbok]

Yeah there was ALOT of black dust. Was a large black cloud that I had to step back from. Not sure when (if ever) it was cleaned out.