Small Engines (Lawn Mowers, etc.): Deere 285 Lawn Mower Low Idle Under Load, leaf attachment, piston rings

Question
I have a John Deere 285 Tractor. When I switch on the deck to engage the blades or leaf attachment, the idle goes very low. Is there an electric high idle switch on this unit? If so, can you help me locate it? or if that's not the problem, what is?

Answer
Casey
There is no high speed switch. Sounds like the carburetor has problems.
Problem: Engine lacks power (possibly after warmup).
Possible causes:

Old gas, bad spark plug, very thick/dirty oil.
Choke is partially closed.
Carburetor needs adjustment or service.
Ignition not timed correctly.
Air filter is clogged.
There is a lack of lubrication.
Valves are not sealing properly.
Piston rings are not sealing properly.
Head loose or head gasket blown or damaged.