The fact that it still runs with the blades off tells me you have a safety switch issue. With a little searching you should be able to find a troubleshooting guide for figuring it out.

I have this machine and I've had these safety switches give me a few headaches over the years!

You won't really know unless you have a way to verify if it is losing spark or fuel. A temporary way to disconnect the kill wire -like a quick inline switch w/ pigatail could be helpful. Don't discount the mechanical fuel pumps on these either. As they sometimes will quit warm out of the blue. It is strange for what's inside- but it happens.

I have an LT155 and had a similar problem. The problem started out as you said. I thought at first that it was not getting gas and checked among other things the vent hole on the gas tank. I finally reached the point where it became very difficult to start. After two trips to the dealer, they realized the condenser was dead. It is easy to replace and is relatively cheap. So you may considering just replacing it and not getting the dealer involved.

No condenser on an Lt155. Ignition is solid state.

On my 2000 LT 155 there is a condenser, or equivalent. It was replaced by the JD dealer and it solved the problem. I found the manual on the Kohler site. I have a copy if some one would like it.

This is from the Kohler Manual: Operation
As the flywheel rotates and the magnet assembly moves past the ignition module, a low voltage is induced in the primary windings of the module. When the primary voltage is precisely at its peak, the primary circuit is interrupted, inducing a high voltage in the secondary windings. This high voltage creates a spark at the tip of the spark plug, which ignites the fuel-air mixture in the combustion chamber. The timing of the spark is automatically controlled by the module. Therefore, other than periodically checking/replacing the spark plug, no maintenance, timing, or adjustments are necessary or possible with this system.

Measure the resistance of module secondary using an ohmmeter (see Figures 8-2 and 8-4):
Zero ohmmeter before testing. Connect one ohmmeter lead to laminations (A). Connect the other lead to the spark plug terminal (C) of high-terminal lead.
With the ohmmeter leads connected in this manner, the resistance of secondary should be 7,900 to 18,400 ohms.

4. If the resistance is low or 0 ohms, the module secondary is shorted. Replace the module*.
If the resistance is high or infinity ohms, the module secondary is open. Replace the module*.

If the resistance is within the specified range, the module secondary is OK.

Thank you everyone.. Will def. send this info onto my husband and hopefully get this fixed before the leaves start to fall.

Any internet links will be helpful since we no longer have a manual for this guy.

Did you find a manual yet? If not, I can e-mail you a shop manual I found a while back.

jasoninbria: having issues with the choke. can you send a copy of any technical info you might have to help with this issue. thanks