Out of ideas

I Briggs single cylinder 19hp 31N807 0440. On a Troybilt zero turn with 42" deck.
I changed the cam, put everything back together. And it ran fine & dandy. My compressor must've been low on air when I tightened the PTO up, because after about 30 minutes of mowing, everything started vibrating. Found that & tightened & down with the bigger air gun.
Mowed for another hour or so, then all of a sudden, it lost all power. It didn't smoke. But would run at like a really low idle. Then stopped. Now it won't crank at all.
It's got spark to the plug. I thought it might be the fuel solenoid, so I snipped the nipple off of it.
The compression check only showed about 48lbs. (I'm not sure how much compression it's supposed to have)
Also, I noticed that after only about 1.5hrs the spark plug was black & wet. Although the oil is brand new. Oil is showing a little low on the dipstick from where it was when I first refilled the oil.

Oh yeah, and I took the flywheel off, and cleaned it, blew the dust & dirt out of the alternator. Then inspected the key/keeper.

The fuel pump is pumping. It's getting spark.
There's no stalling when it it turns over at all.

Any suggestions?

Compression is to low. Did it have oil pump and you forgot to line it back up with the cam. Thinking if that was case it wouldn't have ran that long. But low compression. Leak down test it and listen to the air and see where it is coming from. Then go from there.

Luffydog said:

Compression is to low. Did it have oil pump and you forgot to line it back up with the cam. Thinking if that was case it wouldn't have ran that long. But low compression. Leak down test it and listen to the air and see where it is coming from. Then go from there.

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No oil pump. I checked the valves just a few minutes ago, and the intake push rod was bent. So, I replace it. It cranked and ran for about 5 seconds. Then popped and died.

Possibly and stuck valve or valves might be out of adjustment. Make sure the poppets are there

Did you pull the head off and change the gasket ??

Luffydog said:

Possibly and stuck valve or valves might be out of adjustment. Make sure the poppets are there

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What is a poppet? Never hear anything called that. I readjusted the valves yesterday, and they were moving fine, so it seemed.

Boudreaux In Eunice La. said:

Did you pull the head off and change the gasket ??

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No sir, not yet. Planning on checking what's under the valve cover today, and go from there.

The valve caps is what I meant

Luffydog said:

The valve caps is what I meant

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Oh yeah, they're still on. Ya gotta be careful with those little boogers.

Rechecked the valves, and they're still in adjustment. Now, it turns over about 5 rounds and has like a kick back sort of thing going on, with a pop. Since the push rod was broken, I couldn't compare the one I replaced it with. I could tell there was no major length differences. It was the aluminum intake push rod. The steel one (exhaust/Top) isn't bent.

Compression is too low for sure if it is only 48psi. Recheck flywheel key.

If the compression is low then you got a bad head gasket, those are a common problem on those OHV engines....

Make sure the push rod you put in there is in the exact spot for it... A lot of people including me have missed it by a 1/4 inch before......