Cub Cadet LT42 with Kohler KS540 engine. No start

McRider

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My mower has been getting harder and harder to start and now will not start at all. I have done the following diagnostic steps:

1. Checked it has spark. It does, and will run briefly with starter fluid.

2. checked it has fuel to the carb. It does.

3. checked that the fuel solenoid works. I took the solenoid off the carb and the plunger retracts when the ignition is turned on.

4. I disassembled the carb and blew out all the jets and orifices.

5. checked compression by turning the flywheel and it seems to have plenty

6. attempted to start with air filter removed and still no start.

Although I don't think it's part of the problem, I notice the choke linkage is pretty micky mouse but it works, But the throttle linkage does not have a direct connection between the throttle and the carb. I can move the throttle lever, but it doesn't move the lever at the carb. And yet, the link rod is connected at both ends. I saw this before I took the carb off and even tried to start the engine while manually opening and closing the throttle butterfly at the carb. Still no start.

Logic implies the carb is somehow at fault despite trying to clear it. When looking at replacement carbs on Amazon, I get $130 if I search on Kohler KS540 carbs, and I get $24 if I search on Cub Cadet LS 42 mower. Is it worth paying three times as much?

Mower has 93 hours on the meter.

Anybody have any insight on what I might try next?
 
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mechanizm

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see if it fires with starting fluid. if so then check to see if your carb float bowl is full of gas. If NOT, check your fuel lines to see if it's getting gas. If it is NOT, check your fuel pump. If the fuel pump is good then make sure your vacuum lines going into the fuel pump are not leaking even a tad. I sprayed all of my fuel line connections with a gas/2stroke mix and that seals the lines and allows the fuel pump to suck gas into your carb.

If your carb float bowl is full of gas it's likely a clogged passage. Remove and clean all of those little passages with a guitar string. Go on ebay and see what a cheap chinese carb costs. I kept fiddling with my John Deere L120 for years but then bought a $15.00 carb on ebay and it's been running great.
 

McRider

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  • / Cub Cadet LT42 with Kohler KS540 engine. No start
It does start with starter fluid. Float bowl has gas. There is no fuel pump, it's gravity fed. Took the carb apart and blew out all the jets and passageways.

Took the mower to a shop for diagnosis. Have not got a reply yet.
 

mechanizm

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  • / Cub Cadet LT42 with Kohler KS540 engine. No start
It does start with starter fluid. Float bowl has gas. There is no fuel pump, it's gravity fed. Took the carb apart and blew out all the jets and passageways.

Took the mower to a shop for diagnosis. Have not got a reply yet.
just buy a cheap carb on ebay slap it on and go.
 

McRider

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I did buy a cheap carb off Amazon. It wasn't quite a "slap it on" job, as the new carb had some differences that made the job more difficult, but it does work and the mower runs now.
 
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