Intake valve not opening.

bobson2

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Started the mower STC48V 24BS that has a 24 hp Briggs twin cylinder engine. It lacked power and, as I looked into it, one intake valve was not opening. The push rod was free and the adjuster and lock nut were lying loose having come off the rocker. I put everything back together but the intake push rod does not move it appears that the lifter is not moving. Any thoughts on what I should do next?
 

slomo

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Started the mower STC48V 24BS that has a 24 hp Briggs twin cylinder engine. It lacked power and, as I looked into it, one intake valve was not opening. The push rod was free and the adjuster and lock nut were lying loose having come off the rocker. I put everything back together but the intake push rod does not move it appears that the lifter is not moving. Any thoughts on what I should do next?
Sounds like you over-heated the engine. Valve guide moved away from the combustion chamber. Push rod laying in the engine push rod tunnel.

These are air cooled engines. You need to take the engine cover OFF every year or more, to clean the block and cooling fins. If you are scalping much or even 1 yard, you need to clean the fins. Scalping and bagging are filthy chores. This procedure is in EVERY mower engine slash small engine manual known to man. If it's air cooled pay attention.
 

ILENGINE

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Most likely the tappet is stuff in the up position and you missed the end of it when reinstalling the pushrod. Need to take a look down inside the pushrod cavity and find the tappet and us the end of the pushrod to push it back down, being aware that is may be somewhat stuck.
 

slomo

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Pull the engine cover. Take a picture of your block and cooling fins. Post them up here.
 

bobson2

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Sounds like you over-heated the engine. Valve guide moved away from the combustion chamber. Push rod laying in the engine push rod tunnel.

These are air cooled engines. You need to take the engine cover OFF every year or more, to clean the block and cooling fins. If you are scalping much or even 1 yard, you need to clean the fins. Scalping and bagging are filthy chores. This procedure is in EVERY mower engine slash small engine manual known to man. If it's air cooled pay attention.
I did pull the engine cover and there was some debris in the fins but not a whole lot. Blew it out. What would you do next? Take the head off or pull the engine and take a look at the camshaft?
 

bobson2

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Most likely the tappet is stuff in the up position and you missed the end of it when reinstalling the pushrod. Need to take a look down inside the pushrod cavity and find the tappet and us the end of the pushrod to push it back down, being aware that is may be somewhat stuck.
I will try to get a good look at the tappet but it is not easy with so much metal in the way.
 
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