QuestionWhile cutting today on a Toro TimeCutter 17-42Z Model 74350 the engine speed/rps suddenly changed to an extremely high rpm. There was no noticeable difference in the forward speed of the machine, just the rpm's on the engine.
The throttle adjustment had no impact on the rpm's. Attempting to lower the throttle or raise it gave no effects at all. Pushing the throttle to a full choke position would cause the engine to stall out.
After removing the plastic cowl and looking at the carb it appears that as as soon as the engine is cranked one of the valves slams into a completely open position. Looking down at the carb there are 2 valves. The left or rear vale is the one that opens completely. The front valve if manually positioned will cause the engine to return to it's normal rpm's. It sounds as if the governer is messing up or a tension spring popped off.
After looking at several diagrams of the assemply I cannot see where one is missing but then I am mo mechanic either.
Any ideas or suggestions as to what I need to look at to brings the engine rpm's back to a normal level?
AnswerTake a look at the link below and let me know if it helps.
http://www.briggsandstratton.com/engines/support/frequently-asked-questions/Adju...
You can also check out Toro's website. I did see a set-up manual which may cover throttle cable ajustment. Based on what you described though I would check the governor system.
Let me know what you find.
Eric
