mtsu_av8er
Well-Known Member
If you can't preheat the engine when it is below 20F you shouldn't start it peroid!
LMAO . . . close the banks and cancel the mail!!!:rotfl:
NOT an option once you leave flight instruction and fish spotting.
If you can't preheat the engine when it is below 20F you shouldn't start it peroid!
Very risky!!
not good advice
Why will pumping the throttle increase the risk of a fire? Because of extra fuel being injected? How about in aircraft without a fuel pump connected to the throttle? How is this different than pumping the primer when the engine catches?
Just curious...I've never heard of this being risky.
I believe it's a matter of where the fuel is going when you pump the throttle. It's going into the carburetor, where it can pool if the air is not flowing steadily into the engine. A backfire could cause it to ignite. When you prime the engine with a primer, the fuel is going directly to the cylinders. If you did not have an accelerator pump attached to the throttle, there is no risk, but no benefit either, since pumping the throttle would do nothing.
Our chief mechanic used to lecture us on not to pump the throttle at flight instructor meetings and, after he was done, our Chief Flight Instructor would tell us how to do it properly.![]()
If you pump as you crank, there is probably little risk, since the atomized fuel will be sucked into the cylinders. It's when you pump for a while and then try to start that the larger danger occurs, so they say.
Since the flight instructor turnover has been so quick in the past decade, this issue might be less well known than it used to be. The prevalence of fuel injected engines also makes it less relevant.
Good to know!
I always pumped as I cranked, and never saw a reason to pump before cranking, so I guess I've been safe without knowing it.
But yes, only pump when cranking. . .no other point for me to pump the throttle just for the hell of it.![]()