valve lash

gregjo1948

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Working on a Briggs single cylinder 17.5 hp. I need to know what to set the valve lash at. thanks, gregjo1948
 

ILENGINE

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Assuming OHV engine and not flathead the setting would be .004-.006 for both valves.
 

gregjo1948

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Thanks ilengine. It is an overhead valve engine. Did Briggs even make a 17.5 hp flathead? gregjo1948
 

ILENGINE

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In theory I am sure they did. Could of just been a relabeled 16 or 17 hp engine. There was a lot of that several years ago. I saw a 40 series opposed twin briggs several years ago with a 12.5 sticker on the housing. that was normally a 16 if I remember correctly.
 

Tinkerer200

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Actually the 40 series opposed twin started out as a 12.5 hp. It grew to a 14 hp then finally a 16 hp. At the end of the run of 42 and 46 opposed twins several different stickers were stuck on the remaining engines, lower than their original rating and generally ending in .5. All the other remaining flat head stock was done similar.

While Illinois is a pro and his settings will work, actual spec is .003"- .005" for the Intake and .005"- .007" for the exhaust. I go for the min. on the Intake for compression release reasons.

I can send you detailed instructions on setting the valves AND a Service Manual 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
 

PTmowerMech

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I have an 11 or 11.5hp opposed twin out there somewhere. But with everyone wanting 20+hp's now, I haven't bothered with it.
 

ILENGINE

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I have an 11 or 11.5hp opposed twin out there somewhere. But with everyone wanting 20+hp's now, I haven't bothered with it.

And that is a story for another time. Everybody knows horsepower sells, but why does it now take 25 hp to run a mower that used to only take 10 hp years ago.
 

PTmowerMech

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Has anyone tried to put a 10hp on a zero turn that came with a 25? I wonder if it would last very long. I'm sure with the right carburetor mixture , it would turn the blades fine.
 

7394

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A Zero has a lot more load on the engine from the 2 pumps & super fast blade tip speeds. I think the makers know what power a Z needs.
 

cpurvis

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Plus ZT's have upped the mowing width and mowing speed.
 
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