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Why does my Craftsman Mower run for a short time then lope and foul plugs?

The mower is three years old. It lopes high and then low. Had to replace stretched govenor spring and thought that was the problem. Replaced plug and two minutes later it is black and fouled.

CRAFTSMAN 91738841

Craftsman , Lawn Mowers , Wall Ovens , Lawn & Garden
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1 Answer from this member:
Manage My Life
Since the spring for the Governor was stretched also, check that the governor lever is operating at all. It might be a failed governor assembly is not allowing the engine to increase RPM properly when you increase the throttle setting. Since the carburetor would still be opening, the engine would run poorly and too rich and the spark plug would eventually load up with unburned fuel and foul out.

If moving the governor lever manually seems to help, or the lever will not move at all, then that is likely your problem area.

If the governor seems to respond properly, check that your air filter is clean and installed properly as too little air also means too much fuel in the incoming mixture.

If there is still no improvement you might have a problem with the carburetor itself.

You can see more details, such as those below, in your

Owner's Manual

or at the

Sears PartsDirect

site using the model of your engine, which is 143.006714, but we recommend any carburetor work or repair be done by a professional to assure the unit runs safely to its full potential and still meets all emissions standards.
by Manage My Life
April 29th, 2008
0 votes
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