'09 Cub cadet LTX1040 - won't start-

[motoracerx]

I've been posting in this thread, http://www.tractorbynet.com/forums/cub-cadet-l-g/338880-ltx-1040-wont-run.html, but figured I'd start my own.

I bought the mower knowing that it didn't start. I was told that they mowed the grass last friday, shut it off and attached the hose to the mower deck to clean it, then tried to start mower and nothing but a single backfire. Motor cranks but does not fire.

- There is spark
- No OEM fuel pump on this sv590-0220 19 HP Kohler, so there is no 'bad' fuel pump to contend with
- Good fuel flow from inline filter to carburetor
- New spark plug and correctly gapped at .030
- Clean air filter/breather assembly
- Removed and thoroughly cleaned carb with carb cleaner and compressed air
- Installed new carb solenoid repair kit from dealer
- New carb solenoid was tested by connecting the electrical connectors and the plunger engages/disengages with the key off and on
- I have 12 v going to the carb solenoid connector
- Battery is new and strong and I keep it charged after a series of 'cranking'.
- Fresh gas, 3/4 tank.
- Oil level is good

-If i throw some gas into the carb so that it gets into the cylinder, it will make one big backfire and that's it. Same goes for a shot of carb cleaner into the carb/cylinder.

One other point, apparently I have a fixed main jet and needle carb. However, the needle isnt seated squarely. Is that an issue? Here's a pic of the bottom of the needle, looking up through the bottom of the carb.


Any other thoughts, suggestions?
I feel I've covered everything except for some internal problem.

I have a compression tester but it doesn't fit the Kohler engine. Guess I could go buy one to check the compression.

 

[motoracerx]

....and, getting no fuel to the tip of the spark plug??? wth

 

[motoracerx]

0 psi compression

 

[motoracerx]

Took the valve cover off....the rocker arm on the EX side practically fell off the valve spring and push rod.

When I turn the motor by hand and the valve opens or closes, the rocker will become tight again.

The IN side doesn't have any looseness or play.

Did something break on the other end...?

 

[amaxwell]

Is there a cover over the valves to remove, so you can check to see if they are opening and closing properly. The backfire could have bent or broke one . Both valves open = no compression. Another possibility is a hole blown in a piston. (hopefully not).

 

[motoracerx]

Is there a cover over the valves to remove, so you can check to see if they are opening and closing properly. The backfire could have bent or broke one . Both valves open = no compression. Another possibility is a hole blown in a piston. (hopefully not).

Yes, I took valve cover a bit ago....EX rocker arm literally falls off the push rod and valve spring. Here's the pic.

When I turn the motor by hand, the EX valve isn't pushing outward. It retracts a bit and then extends just a bit...maybe broken valve spring.

IN valve is right at spec @TDC.

 

[amaxwell]

Is the push rod broken or bent ? It should be as tight as the other one.

 

[motoracerx]

Is the push rod broken or bent ? It should be as tight as the other one.

Nope. Push rod is fine. EX Valve is in tact as far as I can tell by looking through the EX port. Research and a youtube video is telling me it could be the valve guide on the EX side. Apparently when the engine gets hot or too hot, the valve guide can come loose and shimmies up the valve. Something is definitely wrong with the valvetrain.

I put the mower back together and been researching all dam n day.

Gawd, I didn't know these Kohler courage engines are the worst ever made...that's the consensus anyway. Can't find one positive review about them.

 

[Bob_Bainbridge]

The "bad" valve looks to be lower in height than the good one. Is that normal? If not it would indicate a stuck/bent exhaust valve which could also indicate piston damage.

Bob B.

 

[oldpilgrim]

broken valve spring ? Something stuck in the chamber, holding the valve open?