Maximum safe RPMs

[loneagle]

I am wondering what the max safe RPMs are for my Tecumseh snowblower engine? I also need to know how to limit the throttle opening to make it live for awhile? I'm not sure if the governor will still adjust with the way I've hooked up the throttle. Suggestions please!

 

[Kenny_McCormic]

I wanna say as high as it can spin.

 

[oscaryu1]

No idea about Tecumsehs, but I'd say not over 5000.

 

[Russ2251]

Probably between 6 to 7k. No fear of flywheel explosion unless some other mod has been made.
Engine manufacturers take into account that governor failure is a real possibility and purposely "over build" them. They don't want customers to be injured or possibly killed.
No stock engine has unlimited rpm's.
An undersized venturi is one way of limiting top end speeds. This is true of all unmodified 'all purpose' engines.
Nothing to fear if governor is not used, as long as nothing else has been changed/modified and engine is used under a load when excessive rpm's are encountered.
Loads are really good at smoothing out combustion pulses.

 

[oscaryu1]

Probably between 6 to 7k. No fear of flywheel explosion unless some other mod has been made.
Engine manufacturers take into account that governor failure is a real possibility and purposely "over build" them. They don't want customers to be injured or possibly killed.
No stock engine has unlimited rpm's.
An undersized venturi is one way of limiting top end speeds. This is true of all unmodified 'all purpose' engines.
Nothing to fear if governor is not used, as long as nothing else has been changed/modified and engine is used under a load when excessive rpm's are encountered.
Loads are really good at smoothing out combustion pulses.

Is that really true? A Clone with just the governor removed can hit 5300RPM-5900RPM before the valves float. I recently read up where a flywheel shattered at 5700RPM...

But then again, China doesn't have quality control...

 

[loneagle]

Thanks, Russ! Another very informative post. You're a great asset here.

Sorry, but I prefer not to buy the Chinese stuff. I go out of my way to avoid it!

 

[Kenny_McCormic]

Is that really true? A Clone with just the governor removed can hit 5300RPM-5900RPM before the valves float. I recently read up where a flywheel shattered at 5700RPM...

But then again, China doesn't have quality control...

Thats china. Gov failure DOES happen, 30 some odd year old 8hp briggs log splitter decided to lose a linkage one day BRAAAAAAAAAAAAAAAAP!, SHUT IT DOWN!!!!!!!.

 

[jr dragster T]

Why shut it down? split those logs quicker:arf: Just kidding.

 

[Russ2251]

I recently read up where a flywheel shattered at 5700RPM

Yup, and some folks have been abducted and probed by aliens. It must be true because I read it somewhere. Believe nothing of what you hear and...you know the rest.
Only once have I witnessed a flywheel explosion. It was because flywheel was heavily modified and was then able to reach/pass its terminal rpm. Could also have been due to improper torquing.
An ungoverned engine running at full speed and no load is much more dangerous than the same engine with a load.
Loneagle will not have a problem. He will never achieve red line rpms with his application, governed or not. Same goes for most engines out there.

 

[oscaryu1]

Yup, and some folks have been abducted and probed by aliens. It must be true because I read it somewhere. Believe nothing of what you hear and...you know the rest.
Only once have I witnessed a flywheel explosion. It was because flywheel was heavily modified and was then able to reach/pass its terminal rpm. Could also have been due to improper torquing.
An ungoverned engine running at full speed and no load is much more dangerous than the same engine with a load.
Loneagle will not have a problem. He will never achieve red line rpms with his application, governed or not. Same goes for most engines out there.

I recently read where a CLONE flywheel shattered at 5700RPM...

 

[Kenny_McCormic]

Why shut it down? split those logs quicker:arf: Just kidding.

He was bottoming out the ram/slipping the belt to load it down while i ran and killed it.

 

[Jerryburger]

EITHER WAY........ If loneagle gets to run that motor safely up to 6k, that'd make for a pretty kart-able motor!