I've heard of it but never witnessed it. I used 90 psi and never had problems. Someone told me I shouldn't be using more than 25 psi or damage may occur.TownWrench said:Has Any One Ever Heard Of Not Using Compressed Air To Clean Out Carb Reason Being This Can Damage Inturnal Check Valves?
The current carbs used on saws and trimmers are different than what was used even a few years ago. I mainly work on Stihl, and most current models may have several very small and delicate check valves as well as an accelerator pump with an o-ring that squirts a small amount of fuel into the venturi when the throttle is snapped open, to aid in smooth accelerating and not have the engine bog down or stumble. So to answer your question, use a brake cleaner spray, not a carb and choke spray, to rinse out all the passageways in a carb you are cleaning. I always wrap the carb in a rag and just expose the hole I want to spray through, because no matter which hole I am spraying into, the spray always comes out and right into my eye! Choke spray is too harsh and may actually damage a check vale, but brake spray is much gentler, and will flush out old fuel. Then use some air to spray out the carb, just don't force high pressure air through every little hole or you can damage the check valves. If a carb is all varnished up with stale fuel, I have had very little success in getting the check valves to work properly. I have tried an ultrasonic cleaner, and it does a great job of cleaning, but the check valves usually leak and so the carb will not work.TownWrench said:Has Any One Ever Heard Of Not Using Compressed Air To Clean Out Carb Reason Being This Can Damage Inturnal Check Valves?