Valve adjustments

small town guy

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I have adjusted the valves on a Briggs 17.5 HP OHV motor to .004. When it is cool or sets for a while it fires right up. If it warms up and then is shut down, it is a problem to start and acts like the valves haven't been adjusted and either starts very hard or not at all. Any ideas?
 

BlazNT

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Adjust valves at a little past top dead center on power stroke. Both valves closed and engine cold. Since you did not include model number no way to tell if you are setting correct gap.
 

small town guy

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Adjust valves at a little past top dead center on power stroke. Both valves closed and engine cold. Since you did not include model number no way to tell if you are setting correct gap.

Thank you for replying. It is a Briggs, model 31C707. I am fairly mechanical but am not a mechanic and have never adjusted valves before. I simply watched a youtube video for instruction. Apparently, I didn't have things in the proper position while doing the adjustments.
 

BlazNT

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Intake .003 to .005
Exhaust .005 to .007
A lot of people like to set it in the middle. I on the other hand like to set it at the smallest then it will have more area to cover over a period of time before it goes out of spec again. So I would set them at .003 and .005
 

small town guy

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Intake .003 to .005
Exhaust .005 to .007
A lot of people like to set it in the middle. I on the other hand like to set it at the smallest then it will have more area to cover over a period of time before it goes out of spec again. So I would set them at .003 and .005

Thank you. I followed your suggestions and it now starts and runs good. I appreciate your help.
 
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