Need a little advice please. have a husq, 2454. 3 years old. shut off when done and would not start. gas, spark, took to dealer, said it was pushrods bent. told ,me to never shut off engine on full throttle. OK didn't know that. got back cut grass yesterday, turned throttle down and shut off, would not start again. what am I doing wrong? new pushrods and labor 200 dollars. cant afford that everytime...... thankyou