Cub Cadet 0 turn power problem/center blade not cutting completely

[CCdog54]

Greetings. I did a search but did not find any posts related to my issue.

I have a Cub Cadet SZ 54KH zero turn. I have done the basic maintenance I do seasonally, (Air/oil filter/oil change) I recently put new blades on it. The center blade seems to not cut like the ones on the outside. I isolated the center spindle and tried to move the blade, thinking it may be loose, but it is not. With the cover off and mowing I noticed the belt appear to be loose. Q Should the belt always be held tight against the outside pulleys?

Power issue: When mowing, not just in tall grass, I seem to lose power. I have to let off the gas and give the mower a chance to get RPM's back to normal. It's almost like I can hear a ticking sound. I have replaced the spark plugs this spring. They were purchased from the dealer when I bought the air/oil and filter.

I don't know what else to troubleshoot.

 

[bertsmobile1]

Check the owners manual for the belt routing
My first guess is you have run it wrong
On a mower with an electric PTO the belt should always be tight enough that turning 1 blade by hand will make all of them turn
Also check you did not accidentally put the blade on upside down .

 

[CCdog54]

Thanks for the reply.

The blades are on correctly, and I used the owners manual to put the belt on. I isolated the center spindle to see if the blade was loose or if the blade would turn independent of the other two and it did not.
When I turned one blade by hand with out isolating any of the other spindles, they all turned in unison.

One question came to mind, if the belt is in need of replacement, would the rpm's drop under load if in tall grass? It's the original belt and I have had the unit about 5 years. It runs ok w/o engaging the pto, and in average height grass, it seems to cut ok.

 

[bertsmobile1]

Check the owners manual for the belt routing
My first guess is you have run it wrong
On a mower with an electric PTO the belt should always be tight enough that turning 1 blade by hand will make all of them turn
Also check you did not acidentialy put the blade on upside down .

 

[CCdog54]

Check the owners manual for the belt routing
My first guess is you have run it wrong
On a mower with an electric PTO the belt should always be tight enough that turning 1 blade by hand will make all of them turn
Also check you did not acidentialy put the blade on upside down .

The belt is attached properly per the schematic in the manual, which is also on the bottom of the seat. Blades are confirmed attached correctly.

A friend who is more adept with engines thought maybe it was a coil issue. He explained a bad coil would cause the engine to run on one cylinder instead of two. When i changed the plugs one of them was carboned up way more than the other. Is this a sign of unburned fuel?

 

[bertsmobile1]

Your friend is not thinking the problem through
An engine problem will affect ALL 3 blades equally not just the middle blade
A single blade that does not cut properly will be a deck problem .
Do all 3 blades turn together when you move any one of them by hand ?
If not then
belt is worn, loose , routed wrong , not properly tensioned
Pulleys are worn past their useable limit
Tension system has failed .
BEaring have failed