Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

On Jan 1, 2007, at 3:22 PM, Alan A. Keimig wrote:

> FROM:
> Alan A. Keimig
>
> EMAIL ADDRESS:
> alan-a-k@juno.com
>
> COMMENTS, SUGGESTIONS, FEEDBACK:
> I am seeking the probable cause of my Tecumseh engine failure. The
> engine is a HMSK80 8 HP. [From the Sears snow blower.]
>
> I noted the engine running rough and with some vibration just
> before it broke the connecting rod .
> The broken rod punched a hole 1\" x 1.5\" in the case. The
> \'plastic\' governor gear was almost melted beyond recognition, and
> had seized the adjoining gear.
> Please note that some engine hours ago , the engine would not turn over. A local mechanic removed the stuck \"Intake Valve Stem Seal\" used on \"emissionied engines\" .
> [See page 85 of Tecumseh Technician\'s Handbook {3 to 11 HP 4-
> cycle L-Head Engines}.]
> The engine ran well after that procedure.
>
> Thanks for your answers.
>
> Alan Keimig
>

Sounds like the engine was run without oil, seized, was then unseized, and then blew up when the rod bolts backed out.

Hi Guys!
Akemig wrote-
The
> \'plastic\' governor gear was almost melted beyond recognition, and
> had seized the adjoining gear.
> Please note that some engine hours ago , the engine would not turn over. A local mechanic removed the stuck \"Intake Valve Stem Seal\" used on \"emissionied engines\" .
> [See page 85 of Tecumseh Technician\'s Handbook {3 to 11 HP 4-
> cycle L-Head Engines}.]
> The engine ran well after that procedure.

If the governor gear was melted in the first seizure how could it have run well after the repair of the valve stem seal before throwing the rod?
Sounds like low oil or WRONG wt. oil caused the problem in both cases.The melted governor gear indicates some really high heat.
Marc

well first off i dont think on the initial seizure, the problem was a stuck seal.  these are only in place to prevent excess oil from working its way into cylinder head.   where was the break on the connecting rod????  what color is the connecting rod??  does it look burnt??? are there metal deposits on the crank journal?? are the thread on the rod cap stripped or elongated???

Pictures of all the areas that Mech12 mentions would take a lot of the guess work out.