Small Engines (Lawn Mowers, etc.): Snowblower Engine Runs Way Too Fast


Question
QUESTION: Hello,
Was using my 10 year old snowblower when suddenly the engine started running really fast. So fast I thought it was going to blow. Shut it down but whenever I start it it takes off at a super high RPM. I may have hit something small but nothing alarming. It is a Yard Machine Mod #318140129. Is it possible a spring popped off?

ANSWER: Maybe the governor spring popped off or broke or the governor arm screw vibrated loose.  Do you have a Tecumseh engine?

Let me know.
Eric

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QUESTION: Yes it is a Tecumseh engine. I can't get a really good look until I remove the engine but it appears the arm has indeed come off. Guess I have my weekend project already planned out for me. This rough Chicago winter seems to have taken a toll on the old girl. Thanks for your help, I'll let you know what I find.

ANSWER: Be careful with the governor.  The manual can be found online for free.

If you send me the engine model and spec number I can send you the engine repair manual URL.

This is likely your manual:
http://www.smallenginesuppliers.com/html/engine-specs/tecumseh/Tecumseh_L-Head_E

Let me know what is going on BEFORE you tear the engine to pieces.  You can attach a picture of the governor arm so I can take a look at it.

Eric

---------- FOLLOW-UP ----------

QUESTION: Success! Thanks for the manual and the advice. I wouldn't have attempted to tear into the engine. Just needed to remove the engine from the blower to see what was going on. The governor arm wore through the plastic governor and came apart. Picked up a new plastic piece from the local repair shop for $3.50 and the old girl is back and ready for action. I just hope I won't need it. It's already been an awfully long winter.
Have a great day.
Tom K

Answer
Glad to hear you got it running.  FYI, many of the Tecumseh snowblower and tiller engine, horizontal shaft engines, have a good track record for NOT breaking the internal governor spool...this is a good thing.

There were a series of Tecumseh lawn mower engines that were prone to breaking the internal governor gear.  Got pretty good at replacing the internal governor spool but it takes at least an hour of labor to replace...with air tools and pending everything comes apart easy.  The point is to be careful if a friend ask you to repair their broken Tecumseh mower that is running too fast.

Eric