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Discussion Starter · #1 ·
I have a 16,5HP Briggs & Stratton Engine model 28W707 Type 0121E1. Had it for 16 years and did some minor repairs including valve adjustements. Shortly after the last valve adjustement, I had a major failure that initially I thought was incorrectly adjusted valves. When opening the cover I found that the inlet valve push rod was broken, basically after 2 cuts after the adjustement and inspection (it wore out where it goes through the (seal?) plate. I bought a new inlet valve ord, but then when installed and rotating the engine the rod does not move at all. The exhaust valve does move normally. Could a broken tappet be the problem???? I could not figure aout any other explanation, but if so this could be a major repair.... any suggestion?
 

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Possible broken cam lobe or internal failure?
 

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Maybe you installed the rod incorrectly and missed the tappet? Very easy to do, I've done it a few times myself.
 
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I sorta agree with vortec....The tappets are pretty hard metal, doubtfull it broke...Push that rocker aside, probe down with the pushrod, while hand turning eng...till you can feel the cam lobe moving...?
 

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Discussion Starter · #5 · (Edited)
I went ahead and removed the engine and opened the crankshaft case. A major repair by my standards... what I found out was that the problem was that the inlet valve tappet was stuck in the upper position, so when the camshft rotated, it did not touch it (for those that do not know, the push rod does not ride on the cam directly, there is a tappet in between them). What happened is that when the push rod broke then the camshaft would push the tappet without any resistance back, so it would propell it high and "stuck it" in the upper position. Had I known this, I could had tapped hard in the tappet upper part using the metal (exhaust) rod and force it to move down, as I actually did since it would not come out by hand. I hope this lesson works for somebody else if this happens to somebody later on. It would have saved me a lot of trouble as I could have done it without removing the engine working from the valve compartment if I had know the root of the problem. I still have to put the engine back, unfortunately the starter broke while removing it so I still need to get the replacement part, and the crankshaft case gasket too. So more fun still ahead...
Thank you everybody that replied.
 
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