Why won’t my 1989 g2 Yamaha gas cart move

Anna first determine if your engine still turns over or if it is seized. Remove the spark plug and see if you can turn it by hand. Attach a ratchet with the proper socket to fit the nut on the pulley and try to turn it in a clockwise direction. If it turns over, you know it is not seized. Good. You said you replaced the brushes in the starter. Pull the starter and try to engage it while it is not mounted in the engine. This will quite forcefully jerk the starter. Make sure that you somehow secure it to prevent bodily harm or damage to it or the other parts around it. Does it turn and engage while you try to start it in the conventional way.

So we can try and find out what exact engine your cart has. There should be a serial number on the left hand size of the crank case. Let us know what you find. Most likely it starts with something like J38, JA2 or J55

It will help us to help you if you can post plenty of pictures of what you are looking/working at. That way we can see what you see and hopefully guide you with more detail. Post these pictures with your QUESTION. Use this guide Bilder zu einer vorhandenen Frage hinzufügen for that