6216 engine problems

[TimE]

I recently got a 6216 that didn't run. I cleaned the gas tank and the carb. Now it runs but it seems low on power and shakes like maybe it has a miss. What it the proper spark plug and gap? What else should I look for? It is a 16 hp Briggs V-Twin model # 402707 type 014501 code 85031312. Thanks in advance for all your help.

[Josh6216]

The B&S repair manual recommends the following three plugs, with a gap of .030" (.76mm). I'm not an expert able to recommend what else to look for though... Good luck. Standard plug, Champion J-19 LM Resistor Plug, Champion RJ-19 LM Resistor Plug, Champion RJ-12