The pump and the float can both be tested before you pull the carb apart or order any parts.. The pump should pump, and the float, you tilt the carb on it's side so the float will be hanging down and away from the float needle, then as you blow through the fuel inlet you slowly tilt the carb so the dangling float will start to swing towards the needle. The fuel inlet should get closed off fully as soon as the weight of the float starts to press on the needle.

Yup.. About the only other parts you are likely to need would be a float needle jet, or the diaphragm on the fuel pump, part 9. Those are both inspectable though, and testable.

It does seem a bit loose, but I doubt that oil soaked part is going to make a squeak. So when you say it went into forwards and was quiet then reverse and it was quiet and then forward and it made the squeak.. Do you think it was the shifting that changed something, or was it just a matter of time needed for the squeak to start ? It's really important to diagnose things before we pull them apart, because we can't do any tests or find the technique that will repeatedly and predictably cause the issue once they are apart. If we don't know the technique to repeatedly get the issue to manifest, then we can't test things after the repair to be confident we have fixed it. We might have just temporarily cured the symptom without fixing the problem.. If I was you Mat, I'd be putting it back together and riding it and testing it till I'd found the problem. I definitely wouldn't be splitting the cases. Oily parts don't squeak. Squeaks that appear within a certain speed range only, don't sound like anything from inside the engine to me..

I got into quads because I started working on lawnmowers and wanted to expand my knowledge.

Look the parts up on an online parts place like partzilla and they will likely have some way or where, that they will tell you what else that parts fits. https://www.partzilla.com/product/yamaha/5GH-17660-00-00?ref=a5a2e51fd1b12c786666c251d29374489d129825 At the top of that listing click on the button called "clutch" and it will take you back to a parts diagram where you can check each part..

I have always had motorcycles, wanted ATV to move my boat around the yard and do work, haling dirt logs ETC, I needed something stronger than my John Deere lawn tractor, they are a blast to ride, but be careful they are addictive I now have three.