I'm rebuilding the carb on my 96 Xplorer 300. I have 2 vent lines that come off the carb and tee into each other. From there there is a short section of hose connected to a vacuum check valve, then another section of hose not hooked to anything, anyone know where its supposed to be hooked up? Also, how do you know which direction of the check valve goes towards the carb?

 

Any hints as to starting points and fine-tuning for the adjustment screws (idle and air?) on the carb would be greatly appreciated too. Thanks!

 

They ALL fall off (vent lines) eventually! I just replaced the vent line on each side of the carb and would vent up under the tank and zip tie. The one way check valve(bottom of carb) on a lot of em were missing and I would just use a longer vent tube and hook to bottom of carb and let it hang slighly below the bottom of the frame so if any gas leaked it wouldn't get on the trans or any rubber parts. BUT on the left side of the carb(below the upper air vent is the oil injection tube,mounts horizontally into carb body),make sure it hasn't slipped off!!! OPT

 

Thanks OPT. Pretty much confirms what I thought but just wanted to make sure.

The bike seems to be running way too lean. Seems too hot. Pings a lot when I floor it and when releasing the gas. I can dial the air screw almost completely closed and alleviate a lot of the symptoms, but I'm afraid it's not really fixing the problem. The bike doesn't smoke at all and it seems like it should, at least some, to me. Every 2-cycle I've ever owned smoked at least some.

I just put a new jug and a new Wiseco piston and rings in it too. I broke it in with the oil line hooked up and running 32:1 through a full tank.

Any ideas?

 

If in doubt,just pull the small oil injector line off the left side of the carb and if its oily its working! You are NOT the first to complain about the "pinging" noise on the 300s!! They did this straight out of the crate and a lot of hunters wouldn't buy em for this reason! They were just noisier than the 250 engine regardless of what brand piston is run in em! One of the reasons they aren't around any more! BUT they were tough atv engines and I never had an oil pump problem on em!They just pinged and rattled! If you have doubts (seems like people panic on injector systems too much) you can always add a little oil (say 50-1 or 60-1 ratio) to the gas! OPT

 

Thanks OPT. It really helps hearing you confirm all that for me. It makes me feel better because the bike did it when I bought it and rebuilt it the first time over 10 years ago.

I'm pretty sure the oil pump is working because I primed it fine when I rebuilt it and it's consuming oil.

I was just concerned about the lean condition. I really think that's fine too and maybe it's just my imagination. I tuned it a little bit more this afternoon and got it surprisingly better just by riding and re-adjusting, repeat.

Having been raised in a garage and having worked on these things all my life (granted, mostly Yamahas but same difference), I just know that too rich will scare you to death but too lean will kill you.

I may just run a couple more tanks and break it back down just to inspect everything.

I'd just as soon sell it but I doubt I could get much for it. Everything is in surprisingly great shape for one that's 15 years old, so I really don't mind keeping it even though I bought an '09 800 x2 just last week so I really don't need it.

Anyway, thanks again. Your expertise and sharing is sincerely appreciated.

-bob

 

I got the same, don't know where is the hose go or just hang loose