Amazon.com: Briggs & Stratton # 807962 KIT-CARB OVERHAUL: Industrial & Scientific Absolutely correct, 808728 carburetor is no longer available. If your engine data plate has numbers 303777 1118-A1 code 95012611, this is your carburetor kit, shop for best price. My son & I had same carburetor problem with SR1642, ordered kit from Amazon, disassembled carburetor & ran small wire from loaf of bread tie or trash bag tie, minus paper, through all orifices & cleaned with carburetor cleaner, ran like a champ after final adjustments. Take your time & be patient. I would also check air filter & foam pre-cleaner for replacement. Let us know how it goes.
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This is just concerning carburetor, Honda Tech has right idea concerning power loss.