Valve adjust

Carscw

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I was taking to race cart engine builder. He showed me a fail proof way to adjust valves. I know this will start a big thing just like what oil to use so I tried it on 6 different brands and hp engines. Then checked the valves the way the manufactures manual said to do them. All valves were dead balls on. Take the valve cover off take spark plug out turn fly wheel counterclockwise until one valve is open adjust other valve to specks repeat for the other valve. I did this on a briggs , kohler , and Tecumseh single cyl And on 2 briggs and a Kwai twin cyl I have always adjusted valves on a Chevy and ford v8 this way but never thought to try it on a small engine. I if you do not agree with me of my findings just say so. Be nice and I shall be nice.
 

Mike88se

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Let me find the specs for a Briggs 12F702 and I'll try it out.
 

pugaltitude

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Thats the way I was taught when I was an apprentice as in theory with one valve open the other should be closed.
That was on cars.

The only thing on small engines is the decomp can sometimes cause adjustments to be wrong which is why I do 1/4 past TDC on the power stroke.

But when you do a leakdown test on a cylinder it says to have piston at TDC. :confused2:
 

Carscw

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The 1/4 past TDC is what confuses people they don't know how to find it.

I use a dowel I put a line on it with piston up and a line with piston down then a line a 1/4 from the top line.

Turning the fly wheel counterclockwise I was told is so the decomp will not engage.
 
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