Cub Cadet LT1045 hard to start

[massination]

I bought a used Cub Cadet LT1045 a couple years back (Kohler Courage 20HP, 150hrs), and ever since I've had it its been hard to start. Especially compared to the Craftsman Riding mower with Briggs engine I had before that. That one would crank right up every time in about 2 seconds.

Basically when first starting it cold, with fully charged battery, it takes about 15-20 seconds of cranking to get it going. Engine and starter turn fine, it just takes some cranking to get it started. Then, when I cut it off, if I don't drop the idle all the way down for 30 seconds or so, it will backfire pretty good. Also, if I walk away and come back 5 minutes to 30 minutes later, it takes a lot of cranking to get it going. The engine is still warm, so I'm not opening the choke. Usually, it will instantly crank up for about 1-2 seconds, and then cut off, like its using up the gas it has in the carb, but runs out or something. Then, when I try to start it again, it usually takes at least 30-45 seconds of cranking to get it going. Sometimes I'll stop and let it sit, and come back in a couple minutes and sometimes it will crank right up. To me it seems like its either flooding itself after I'm cutting it off, or maybe its not getting gas for some reason. I don't have experience with this engine, but I would appreciate any help or tips people might have. I did replace the spark plug today and tried cranking it with the air filter off as well, but neither helped. Seems like I replaced the fuel filter last year in my attempt to get it working right, but that didn't work either. As another test today, I sprayed starter fluid in the air intake and it cranked right up immediately, then cut off a second later. 4-5 times of doing that finally got it started and it stayed on. Maybe its some type of carb issue?

Any ideas? I really appreciate it.

 

[tomplum]

It does sound fuel system related if it is cranking over OK. 1) Fresh fuel 2) verify that the fuel cap is venting (unless yours has the vapor return line in which case ensure that it isn't kinked, though I think this is too old for that. 3) use this OEM fuel filter 2505021s if yours doesn't have a fuel pump. If it does have the pump, pop the line and crank it to see if it will put fuel into a cup. 4) Verify that the choke is closing. Many times this is a cable adjustment. 5) Still no joy you will want to pull the carb or drop the bowl and check for water. Not much else in the carb to clean but while you are there, you will need to know that the anti backfire solenoid is retracting when the switch is on and when cranking + that the rubber tip is not floating up in the stem and is attached to the plunger on the solenoid. If all is good, look close at the tip of the float valve for distortion, wear or swelling. You are now certified....

 

[SandburRanch]

Before killing the engine, try loosening the gas tank cap. I've read where it was thought the tank was under a vacuum on their tractor for gas cap reasons and when killed the gas in the line was vacuumed back. If that doesn't help consider putting a fuel valve in the line, closing it then kill the ignition and see if that helps with cold starting.

 

[Patches]

I have an OLD(1988) John Deere with a Kohler and if I don't run the throttle up to about quarter throttle before shutting it down, it will backfire. I've been told the backfire has been known to dislodge the exhaust valve seat which would certainly make it hard to start. As tomplum said, there isn't much going on in the carburetor, but a check of the fuel shut off solenoid may be in order.