Another small engine question. Briggs 10.5(speeco splitter)

[Davej_07]

Well, I know its not the pump...... Upon further digging I found the exhaust connecting rod and rocker VERY loose and the exhaust valve not opening very much.......im assuming this isnt good?
THe rod doesnt isnt bent or worn anywhere, in fact nothing looks worn or otherwise unusual except its loose. Mayhap I need to take it apart further to find something broken?

Dave

 

[Whitespider]

Dave, your question lacks details and specifics, as well as being a bit confusing.

First of all, a “connecting rod” connects piston to crankshaft… it doesn’t have anything to do with the valves.
Second, what “Briggs 10.5”?? What model?? Horizontal or vertical?? I’m gonna’ assume OHV because you mention “rocker”.
Third, exactly how much is “VERY loose” and “not opening very much” anyway?? C’mon man, your idea of “VERY” and “not very” may be nowhere near mine.

OK, assuming OHV design, a cold engine and valves closed on the compression stroke, the rocker arms should be “loose”… that’s called the valve clearance (sometimes referred to as valve lash). Most any OHV design has adjustable valve clearance, typically by way of an adjustment screw and locking nut affair. The valve clearance specification is model/serial number specific and may even be different for intake/exhaust… I’ve seen Briggs engines with specs as little as .002 and as much as .020 (By-the-way, .020 is what I call “VERY loose”).

 

[Davej_07]

After re-reading my first post, yup.....didn't make sense to me either

It's a model 210000 vertical. The rocker was so loose that that the push rod was not in contact with the cam or the rocker. The rocker would spin so it was not in contact with either the valve stem or the push rod. The VERY part of loose was definately more than the .005-.007" lash so I adjusted it after finding the tolerances on the Internet. Purring like a kitten once more.
I just can't imagine why the nut loosened up so much in the first place.

Dave

 

[Walt41]

Vibrations do strange things, I have watched fasteners unbolt themselves while an engine is running. It has also been proven that jet planes flying near buildings can back nails out but...back to your engine, you should replace the nut with a locking one like an automotive roller rocker uses. Just head on down to your local auto store and match up the thread, it will be a sleeved nut with a hex head in the center that you lock down to prevent it from coming loose.