Just bought a 2006 Yamaha Bruin 350 4x4 on Saturday.

Problem #1
It seemed to run pretty good, but after riding it for a half hour it died. No warning...just shut off and died. Tried starting it, wouldn't turn over or make a sound. When I turned the key, no lights, no dash indicator, nothing. Figured it was electrical. Took the seat off, and checked the fuses. Noticed that the 30 amp fuse in the starter solenoid relay was toast. Walked to the truck, went to walmart, bought a box of fuses. It blew every fuse every time I turned the key. I was about to leave it and come back for it later, but a buddy of mine showed up to save the day, and we used a screwdriver to jump the posts and get it running. I rode like a bat out of hell to make sure I got it to the truck, and it got me almost out of the woods, and it did it again. This time, I noticed that it was trying to cut out several times while I was riding it. So, tried jumping the posts again....didn't work, but at least the engine was turning over. We got it on the truck, and I dropped it off at my buddies house. He is an ex-mechanic, and now a technician that repairs surgical tables at hospitals, so he is good at troubleshooting, but I'm trying to avoid a trial and error process. Any thoughts on what this could be? Battery is brand new.

Problem #2
Turning the gas to the "On" position doesn't work. Only runs when the **** is on "Reserve". Suggestions?

Problem #3
There is a hose that runs from the bottom of the carb to the back of the engine that drips gas. It usually stops after a little while once the fuel is off (which it shouldn't do anyway), but I noticed when I came back the other day from getting fuses, that it leaked the entire time I was gone, and there was a good bit of fuel on the ground. This does not work for me, because I bought it to take hunting, and the smell of gas is not conducive to being scent-free when I go out to hunt. Any idea what this is?

 

#3 sounds like a sticking float,or needle. Two good vids on it.




or

 

TLC...thanks for those videos. My first thought was a stuck float, so we're on the same page. Once I nail down the electrical problem, I'm gonna take the carb apart and see what's what with that.

 

The fuel issue only working on reserve is the fuel switch or "petcock". It has 2 tubes that stick in the fuel tank with a filter on each tube. The tube and/or the filter could be stopped up. You could easily take it out and blow through it with some air or replace it.

The electrical issue is you have a short somewhere, that is, a positive wire is shorting out to the frame(ground) or an electrical device is shorting to ground. I would start by looking for a wire in the harness that has rubbed the frame to the point the bare copper is rubbing the frame.

 

Think we've got the electrical prob figured out. Previous owners did some backyard mechanic experimenting with the wiring harness...found a lot of splicing and bare wires, and poorly routed wiring (too close to exhaust, some melting, etc.). Picking up a replacement wiring harness and that should take care of that.

Haven't fooled with the carb yet.

 

Update!!

Found a nice used wiring harness on eBay, and I should have it in hand by tomorrow. The other one wasn't secured to the frame, and leaned up against the exhaust in spots, melting wires and leaving them exposed. There were some wires that were cut, and some spliced together. We are assuming this machine experienced a serious electrical problem, and some fool that owned it before me thought he could troubleshoot it.
So, hopefully a new wiring harness will solve that problem.

As far as the carb goes, the float was sticking, and one of the jets came loose (don't know how that happened). Got that all taken care of, and it should be running normally by tomorrow. I'll update with pics as soon as I can.