Make sure there is a bolt or click pin installed through the tire rims and drive axle, check to see if the belt is slipping or possibly you need to replace the friction disc located in the engine frame. Other components are powered by sprockets and chains, so check to see if the chains are aligned, and also you do not have any worn sprockets.
why does my rider cut off when i engage the blades
look for the engage switch that has a picture of blades
You have to engage the PTO clutch slowly because the snowblower has a lot of inertia to it, especially a two-stage blower. Get your RPMs up before you try to engage. Also, make sure that your snowblower will actually turn by hand before you hook it up. It might be jammed with ice or debris or it might need lubricated.
Fix the drive belt.
possible broken auger belt, or one that has slipped off the pulley
May possibly be a loose missing or worn belt.
check to be sure the blades have free movement. usually if you have this problem it is caused from something stopping the blades from rotating therefore it stops the engine
Lever on right side of steering wheel, push up
The STX-38 should have an electric clutch for the mower deck. The switch to engage it is on the right rear fender. It is a toggle switch. You will have to pull up on the switch and forward to engage the blades.
Most lawn tractors don't have any fancy clutch system, but simply use the belt to engage and disengage the blades. When the blades are disengaged, the drive belt is slack and there isn't enough friction to the pullel to drive the blades. When engaged, the belt is taught and the belt drives the blades. Tension is controlled by a spring loaded pulley. When you pull the lever to disengage the blades, you pull this pulley away from the belt. When you engage the blade, the spring pushed the pulley into the belt, tensioning it.
check the front and back belt pulleys and if the elt is on the right side of the engager.
pto switch energizes a vacuum solenoid which puts pressure on the pto belts