So here's the kicker for me. My mower is a Craftsman 21 HP 46" desk Model 917.288522 / Briggs & Stratton Enging Model # 331877 Type Number 2371-G1. I have an issue with my Craftsman B&G 21HP motor. It won't turn past 1/2 but if I have my Dad manually hand turn it past while I'm turning it over it will start. When we take out the spark plug the motor turns over like normal no problem. We first replaced the starter no luck. Then we replaced both intake / exhast valves and rods thinking that was the problem. Still no luck. Any and all suggestions / brainstorming will be welcome.
B&G 21 HP stops on first turn when turning over but turns when sparkplug is out
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SeniorCitizen
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Re: B&G 21 HP stops on first turn when turning over but turns when sparkplug is out
That cranking symptom is usually attributed to incorrect valve lash. If you were to place an amp meter on the starter cable you may find amp draw to be very close to the battery cold cranking amps when it should be only around 150-175 amps.
Can also be a faulty de-compression system. Can be checked with a feeler gauge as a piston approaches TDC on the compression stroke. Try the exhaust valve lash for de-compression first.
That cranking symptom is usually attributed to incorrect valve lash. If you were to place an amp meter on the starter cable you may find amp draw to be very close to the battery cold cranking amps when it should be only around 150-175 amps.
Can also be a faulty de-compression system. Can be checked with a feeler gauge as a piston approaches TDC on the compression stroke. Try the exhaust valve lash for de-compression first.
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Tinkerer200
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Re: B&G 21 HP stops on first turn when turning over but turns when sparkplug is out
"Try the exhaust valve lash for de-compression first."
The exhaust valve has nothing to do with compression release on this engine. I can send you detailed instructions for setting the valves AND checking the compression release IF you like. Address below put in proper format and remind me engine model number and what you want.
Walt Conner
wconner5 at frontier dot com
"Try the exhaust valve lash for de-compression first."
The exhaust valve has nothing to do with compression release on this engine. I can send you detailed instructions for setting the valves AND checking the compression release IF you like. Address below put in proper format and remind me engine model number and what you want.
Walt Conner
wconner5 at frontier dot com
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Re: B&G 21 HP stops on first turn when turning over but turns when sparkplug is out
What's with this private message in proper format crap. Why in hell can't this information be put on this site rather than inventing your own private messaging system.
primerbulb120
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Re: B&G 21 HP stops on first turn when turning over but turns when sparkplug is out
It might be in a PDF or Zip file. Neither of those can be uploaded to this site.
It might be in a PDF or Zip file. Neither of those can be uploaded to this site.
SeniorCitizen
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Re: B&G 21 HP stops on first turn when turning over but turns when sparkplug is out
I treat it as spam anyway so whatever it is let the administration accept the nonsense if they like. However it is, it isn't doing this site one bit of good.
I treat it as spam anyway so whatever it is let the administration accept the nonsense if they like. However it is, it isn't doing this site one bit of good.
Tinkerer200
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Re: B&G 21 HP stops on first turn when turning over but turns when sparkplug is out
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bertsmobile1
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Re: B&G 21 HP stops on first turn when turning over but turns when sparkplug is out