What would cause my blades to run slow. The motor runs fine, just the blades are slowing. I cleaned the deck. Just wondering what else would cause that?

check pulleys and mandrels for failure/ binding

Scott, sounds like belt or pulleys could be worn out, also see if your pulley tension spring is still on the tensioner pulley arm if your machine is equipped.

It depends which type of turntable it is. If a belt one then change the belt, make certain you make a note of how the belt fits before removing it.

Direct drive turntables are more difficult. As it could be any number of faulty parts that cause it.
A build up of grease or dirt in any type of deck can slow the speed down.

A faulty motor on both types of deck will also cause it.

Hi there! There are five general causes for cassette tape machines to run slow 1) motor faulty Check the motor governor electronics 2) Belts and rubbers worn or slipping 3) Lubrication of mechanism bushes 4) Cassettes binding in their cases this is quite common 5) If there is a solenoid or motor that do the work of the moving of capstan roller then there can be something wrong with that it can be binding on the sliding mechanism

It could be the motor run capacitor is decaying in value with heat or the motor bearings need lubrication as well as the capstan bearing.
These unit require a lot of linkage cleaning and re-greasing to make them run right. There is also oil to be placed in the idler bearing points.

This most often happens when you are mowing too much grass at once, or when the deck (or chute if you have a bagger) is clogging for some reason. Sometimes this is made worse by having dull blades. Usually mowing at a slower speed or mowing more frequently will help solve this. If the motor is struggling with the blades, these are usually the culprits. Clean your deck thoroughly, cut the lawn more often, or cut it slower.

In some cases, if your PTO belt may be worn, stretched, or need adjustment. When this happens, the motor will not slow down with the blades but will keep running normally and you may smell a burning rubber smell as the blades slow down.

I presume you are running the engine at appropriate revs :) .... Cutter belt is slipping. Is there any sign of oil on it? Is there tension on the belt?

sounds like the blade spindles are binding, many have Zerk fittings to grease them. with belt disengaged try turning the pulleys they should turn easily and have no wobble in them. if either is wrong replace spindle and best to change in sets. this is the most common issue.

Im assuming the tractor is a hydrostatic, in this case when the transmission starts to go...thats it, call the company and find a replacment or get another tractor. unfortunately rebuilding them isnt all that worth it

capstan belt may be failing. check this by removing lid and touch the capstan flywheel when running. if it is easily stalled/slow to come up to speed and or the belt slipping badly then belt will require replacement.