I need a gas tank for a 4000 watt Buffalo generator.

Could be lost exciter current. This is how to restore it - Connect 16 or 18 gauge wires to a 12 volt battery. With generator running, insert bare ends of wires into AC outlet - one to Hot, the other to Neutral. Insert and remove quickly. There should be a flash and power will be restored. If not, repeat until you get that flash and output current restored. Using light gauge wires is so that if you are too slow to remove them once AC is restored. they will burn out before the battery suffers from the AC incoming. Be quick and be careful.

There have been several factories in china that have made the motors used on buffalo generators, a couple of these are Lifan and J.D. as in Jiangdong.All of these motors are very similar to honda motors.The 6.5,13,and 15 h.p. motors are real brutes and hold up very well.

Fuel will go stale if left for a long time. Drain and clean fuel tank and also drop float bowl on carburettor to remove any old fuel. If there is any sediment in the float bowl a carby clean could also be necessary.

Some of these are delivered with gel cell type batteries. They are often undersized and have limited starting capability.

Frankly the best way I have found is to MEASURE the maximum size fo the battery and note the terminal type. The go to the NAPA site and check the dimensiona to find the biggest battery you can fit in... usually a motorcycle type. Usually you need one that has lugs with holes to use bolts to attach the wires.

Idle speed jet or passage and/or high speed jet/passage is clogged. Remove the carb and inspect and clean thoroughly, then re-install. Set idle and high spped screws approx 1 turn and tune to run smooth from there.

If it has been in storage with gas in it. it is gunked up. Need to remove carburetor and take to someone to clean carb.

wow, that is high, i would think voltage regulator is faulty also

The generator engine is jetted for sea level. When you run at 24 hundred feet, it's flooding out. That's what you smell. The carb will need to be jetted for high altitude.

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All generators need to be run once a month. All things from the tank to the and including the carb will get gummed up with dried out fuel. I have a whole house generator and a 5500 watt gen set on my motor home. I keep fresh fuel in the stand alone house generator in California in case of a bad earthquake. I drain the gas after every run and keep all vehicles full of fuel just in case. Run gen sets at least once a month or pay pay pay!!

Do a ohm test on armature slip rings with brushes removed.You should have continuity between rings but not between either ring and shaft.