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On our 21 HP Briggs and Stratton JD lawn mower, the valve stem…

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On our 21 HP Briggs...
On our 21 HP Briggs and Stratton JD lawn mower, the valve stem came loose. We adjusted it. The motor starts and runs even at high rpm. However when I try to mow the lawn, demanding power from the engine, the engine shuts down. I can mow on half speed.
Submitted: 3 years ago.Category: Small Engine
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Answered in 1 hour by:
6/24/2015
Technician: Rex L., Small Engine Technician replied 3 years ago
Rex L.
Rex L., Small Engine Technician
Category: Small Engine
Satisfied Customers: 761
Experience: auto-diesel graduate. small engine and John deere and silver certified in stihl.
Verified
I believe your saying the rocker arm came loose on the valve and you tightened it back up. I would check the push rod that is on that rocker arm and make sure it is not bent. If it is bent that cylinder will be down on power.
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Technician: Rex L., Small Engine Technician replied 3 years ago
Just wondering if you got it fixed.
Please rate my response.
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Category: Small Engine
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Experience: auto-diesel graduate. small engine and John deere and silver certified in stihl.

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