flywheel stops when I try to start it.

2ball

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B and S 17.5 HP I/C. When I turn the key to start it the fly wheel stops at one point. I have to stop, turn the flywheel by hand past the hard point. I have to do this a coupe of times before it starts.
Its getting worse and worse. starter, battery warped cylinder?
 

slomo

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Valve adjustment time...... Should be done yearly if you want to keep a good running engine.

Battery needs to be LOAD tested.

slomo
 

StarTech

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First check and just valves then look for ACR bump of the intake valve. If no bump then camshaft has failed.
 

Rivets

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I’d almost check for hydro lock.
 

2ball

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Just throwing a little more info in this thread. I did buy the engine used and it was sitting in a tractor outside when I bought it. I used it all last season. Every time I ran it i shut off the fuel line before I put it away and let it run out of gas. This time I did not, the gas was left on, and it was very hard to start. After it’s started it runs great.
 
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2ball

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Just throwing a little more info in this thread. I did buy the engine used and it was sitting in a tractor outside when I bought it. I used it all last season. Every time I ran it i shut off the fuel line before I put it away and let it run out of gas. This time I did not, the gas was left on, and it was very hard to start. After it’s started it runs great.
I picked up feeler gages and I will check the valves and I will get to see if it starts after one try when I put the flywheel just after the hard spot. When I put it away I turned off the gas and ran it dry. I may be leaking gas because when I left the fuel line opened, I lost gas. And I could smell gas in my shed where I keep my mower.
 

Fish

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Check your oil level, see if it smells like gas. Take the plug out and see if it is wet with fuel.
 

2ball

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When I first got the engine the needle was completely dislodged from the seat. I put it back and hoped that fixed the gas in the oil issue. I’ll check the oil.
 

arch252

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This is the same problem I just dealt with. Exact same problem. Put your hand over the air intake into the carb as you first try to start it. That will keep it from drawing air into the engine and reduce the internal compression. If it turns over and starts while doing then your compression release has failed and you will have to replace the camshaft. $75 OEM, $30 aftermarket. Looking for the "bump" on the intake rocker will also show this, provided your valve lash is set correctly. Just covering the air intake is a much easier way to check it.
 

2ball

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Thanks for the direction so far. I still need to do them, life got in my way.

I do have gas in the oil. I changed the oil. (the last 2 times I put the mower away I just turned it off, I did not use the fuel cut off, or run it dry)
last time I put it away I turned off the gas and let in run dry.
When I started it up today there was no issue with the fly wheel stopping. It turned over 4 or 5 times until it got gas and started and ran great.

Oil in the gas is still a seat and needle issue?

In theory can I just use it like I am, or am I damaging something?

Arch thanks for the direction, I hope to check that this weekend.
 
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