ChemtoolB-12 in riding mower engine November 26, 2014 Solutions Central › Category: Choke › ChemtoolB-12 in riding mower engine 0 Vote Up Vote Down Batman asked 10 years ago Is it safe to use Chemtool B-12 in my riding mower engine? 1 Answers 0 Vote Up Vote Down chemtooler Staff answered 10 years ago Yes! It is safe as long as it is properly diluted at 1 oz. per 1 gallon of gas. Please login or Register to submit your answer Username or Email Address Password Remember Me