tnhomestead

Old craftsman tiller, pull behind 8 hp B&S, Just out of the shop! Runs fine for 30 sec to few minutes,then cough sputter pop cough then sometimes dies, sometimes goes back to running fine, AHAH says I -- Water in the tank!
So drain the gas, change fuel filter, pull needle valve and drain carb. add fresh gas and vroom,then cough sputter pop, vroom Hmmm maybe gas bad? Added from pump at station! Add HEAT, same ole same ole still!!!! Any ideas? When coughing some black smoke, when running fine none.

manic

Is there a bunch of rust in the gas tank? Might be pinholes in the diaphram
in the carb. The needle/jet may have some bits of debris clogging it.
Only takes a grain of sand. Black smoke=gas=carb issue. Imo..

k2skier

A non seating intake valve will cause a rich running condition. It runs OK cold, after warming valve clearance is gone. When the intake valve doesn't seat it lets in too much fuel. Something to look at.

tnhomestead

Thanks for the suggestions -- I thinkits got a pinhole diaphram leak will find out later thi week~

k2skier

You said you have a 8HP B&S; correct? No 8hp Briggs ever used a diaphragm carb.

tnhomestead

Had to go back on the road, so hauled it to the shop--thanks for all the suggestions,I think its the carb is messed up!