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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?

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

Battery needs to be LOAD tested.

slomo

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

I’d almost check for hydro lock.

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.

2ball said:

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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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.

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

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.

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.

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.

Well do you like broken pieces of metal bouncing inside your engine? Here one fail so badly on a customer engine that it took out the governor/oil slinger.

here is my theory, using my limited knowledge. gas is leaking because of my needle and seat. If the gas is getting combusted, it wont leak into the oil. so when its running it wont leak into the oil. it leaks in to the oil when it sitting not running. so if I use a fuel shut off and run it dry, gas wont leak in to the oil. if no gas is in the oil the engine wont overheat and blow apart.

now fixing the seat and needle is so easy it does not make sense not to fix it.

is there more to it then that?

I have seen a few engines with needle/seat problems where the engine began running too rich.
If you have the engine i think you have, it uses a viton tipped needle, so its just dropping the bowl if there is room, pull the float pin out, take off the old needle , install the new one. Reinstall the bowl.
That way the carb will work properly and you can use the in line cutoff as a back up.

Scrubcadet10 said:

I have seen a few engines with needle/seat problems where the engine began running too rich.
If you have the engine i think you have, it uses a viton tipped needle, so its just dropping the bowl if there is room, pull the float pin out, take off the old needle , install the new one. Reinstall the bowl.
That way the carb will work properly and you can use the in line cutoff as a back up.

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thanks, I have a Walbro carb based on a reply from you last year, when I was trying to identify it.
is there more info that I need to order the pin, or are all Walbro needles the same?

get the engine model, type and code numbers. Should be on the OHV valve cover

Scrubcadet10 said:

get the engine model, type and code numbers. Should be on the OHV valve cover
View attachment 56496

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Is it located here?
I guess I don't really need the engine model number, I need the carb model number.

the carburetor is part of the engine assembly, you need the engine model which is in the picture you posted.
a wire brush or find sand paper/scotch brite will take care of that rust to make it easier to read.

Hoping to find the correct needle and seat from this. Not enough info here?

Engine model number is generally the easiest way.
quite a few LMT models, i personally don't know if they use the same needle. i would assume so. but assuming is not knowing... i think the P/N is usually on the other side of that carb.

The flywheel will be defective, most likely seized, or the battery lacks sufficient power to completely pull the mechanism.