Kohler KT730 cranks but won't start

[gebo824]

My Cub Cadet riding mower with a Kohler KT730 engine cranks but won't start. It's barely a year old (48hrs on it) & ran it to mulch leaves 4-6 weeks ago. Plugs look good & tested it has spark. If I pour a little gas in the carb, it starts right up for a couple seconds, proving good spark & fuel. I removed & tested the shutoff solenoid that screws into the bottom of the carb. The plunger felt a little sticky, so sprayed WD-40 in it. The plunger moves when I turned the key. I ordered a new fuel pump & would have ordered a new shutoff solenoid but couldn't find one on Amazon that looks exactly like mine. One thing I did find was that the breather hose was just dangling loose from the bottom of the air inlet. Hopefully that hasn't been that way for very long or have been sucking dirt into the engine. It was not dirty/dusty under the air filter & sounds fine when runs the second or two from the gas dribbled in the carb, so thinking the engine is ok. I see the hole in the breather plate but no fitting/grommet to connect/hold the hose. I put a bolt in the end of the hose to plug it, thinking too much air & too lean a mixture, but still didn't start when cranked again. I can't find anything online that clearly shows how the hose connects to the plate. Even the service manual I downloaded just shows the hose & plate in a disassembled view with no fitting in between. Surely the hose doesn't just push into the hole! If the fuel pump doesn't fix it, I guess I'll take the carb off & spray carb cleaner thru all the holes/jet. Any other suggestions???

 

[MParr]

My Cub Cadet riding mower with a Kohler KT730 engine cranks but won't start. It's barely a year old (48hrs on it) & ran it to mulch leaves 4-6 weeks ago. Plugs look good & tested it has spark. If I pour a little gas in the carb, it starts right up for a couple seconds, proving good spark & fuel. I removed & tested the shutoff solenoid that screws into the bottom of the carb. The plunger felt a little sticky, so sprayed WD-40 in it. The plunger moves when I turned the key. I ordered a new fuel pump & would have ordered a new shutoff solenoid but couldn't find one on Amazon that looks exactly like mine. One thing I did find was that the breather hose was just dangling loose from the bottom of the air inlet. Hopefully that hasn't been that way for very long or have been sucking dirt into the engine. It was not dirty/dusty under the air filter & sounds fine when runs the second or two from the gas dribbled in the carb, so thinking the engine is ok. I see the hole in the breather plate but no fitting/grommet to connect/hold the hose. I put a bolt in the end of the hose to plug it, thinking too much air & too lean a mixture, but still didn't start when cranked again. I can't find anything online that clearly shows how the hose connects to the plate. Even the service manual I downloaded just shows the hose & plate in a disassembled view with no fitting in between. Surely the hose doesn't just push into the hole! If the fuel pump doesn't fix it, I guess I'll take the carb off & spray carb cleaner thru all the holes/jet. Any other suggestions???

There should be three hoses to the fuel pump. Could that hose go to the fuel pump?

 

[gebo824]

No, the tube in question is item B in the first attachment & J in the second. I just change the fuel pump & still won't run. The hose on the pump goes to the valve cover.

 

[MParr]

The breather tube should connect to the bottom of the air filter box and just to the left of the carburetor bowl.

 

[Tiger Small Engine]

My Cub Cadet riding mower with a Kohler KT730 engine cranks but won't start. It's barely a year old (48hrs on it) & ran it to mulch leaves 4-6 weeks ago. Plugs look good & tested it has spark. If I pour a little gas in the carb, it starts right up for a couple seconds, proving good spark & fuel. I removed & tested the shutoff solenoid that screws into the bottom of the carb. The plunger felt a little sticky, so sprayed WD-40 in it. The plunger moves when I turned the key. I ordered a new fuel pump & would have ordered a new shutoff solenoid but couldn't find one on Amazon that looks exactly like mine. One thing I did find was that the breather hose was just dangling loose from the bottom of the air inlet. Hopefully that hasn't been that way for very long or have been sucking dirt into the engine. It was not dirty/dusty under the air filter & sounds fine when runs the second or two from the gas dribbled in the carb, so thinking the engine is ok. I see the hole in the breather plate but no fitting/grommet to connect/hold the hose. I put a bolt in the end of the hose to plug it, thinking too much air & too lean a mixture, but still didn't start when cranked again. I can't find anything online that clearly shows how the hose connects to the plate. Even the service manual I downloaded just shows the hose & plate in a disassembled view with no fitting in between. Surely the hose doesn't just push into the hole! If the fuel pump doesn't fix it, I guess I'll take the carb off & spray carb cleaner thru all the holes/jet. Any other suggestions???

Make sure fuel pump is functioning. Correctly and thoroughly clean the carburetor.

 

[MParr]

Remove the fuel line from the carburetor. Leave it attached to the fuel pump. Have a container to catch any fuel. Crank it over and see if fuel is exiting the fuel line from the pump.

 

[slomo]

If I pour a little gas in the carb, it starts right up for a couple seconds, proving good spark & fuel.

No, proves the engine will run on the fuel you dumped into the carb for a short time. It proves spark, spark at the correct time, air, your assisted fuel insertion and compression are good. She runs as long as YOU keep pouring gas into the carb.

I removed & tested the shutoff solenoid that screws into the bottom of the carb.

It is called an anti-backfire solenoid. Not per say a shut off.

The plunger felt a little sticky, so sprayed WD-40 in it.

If the plunger is sticky then the carb needs to come off and be cleaned. Sounds to me she was stored with last seasons gas. Hope it's not E-10.

I ordered a new fuel pump & would have ordered a new shutoff solenoid but couldn't find one on Amazon that looks exactly like mine.

Did you TEST the old fuel pump? Good fuel flow AT the carb inlet? Keep your card IN your wallet.

I see the hole in the breather plate but no fitting/grommet to connect/hold the hose. I put a bolt in the end of the hose to plug it, thinking too much air & too lean a mixture, but still didn't start when cranked again.

I hope you didn't just plug off your breather hose.

 

[MParr]

@gebo824
Watch this closely. You will see the hose setup when he removes the air cleaner box.

 

[slomo]

MParr has a better video.