Blades bog down when cutting, but engine doesn’t.

Hello, I’m hoping someone might be able to help me as I’m new to the zero turn world. I just purchased a used Cub Cadet “50 with a Kohler Command 23. It runs like a beast and just gave it a quick tune-up to boot. (Oil and filter change, fuel filter change, spark plug change .030 gap, cleaned the air intake filter and a few shots of carb cleaner). In the new few days I plan to disconnect the deck and clean the underside and sharpen/replace blades if needed. Also there is a dent in the front of the deck which doesn’t seem to get in the way of the blades turning but i’m Going to hammer back out anyways.

As the title summarizes, the engine runs fine, doesn’t bog down even when “flooring it” (not sure of the terminology when i’m using my hands now lol) but when I engage the blades and begin to cut I hear the blades bog down a little bit but the engine doesn’t skip a beat. If I were to stop while the blades are engage I hear them ramp back up to what I assume is full rotation. Being new I have a few ideas but looking for guidance; I have the following as suspect:

-Belt is loose, so when the blades encounter the resistance of the grass the belt starts to slip
-There is nothing wrong and the mower has a feature that auto adjust to the thickness of the grass and when i’m Mowing the blades dial back because they don’t need to work as hard to cut my grass, but I don’t know why the blades would ramp up when I stop if this was the case
-The pulleys/spindles are bad

Any help would be greatly appreciated! Glad to be part of this community and thank you all for reading.

Welcome aboard,

First, there is no such feature that the blades could tell the grass thickness & adjust..

I would suggest looking at the belt for signs of slippage. Otherwise I'm thinking you may be bogging down the engine as well.

Z's are good mowers, but you still need to use good judgement as to the speed you are cutting at.

The Spindles should be checked, just to know good or bad.

https://www.cubcadet.com/equipment/...elNumber=53AA5B7P710&serialNumber=1E116Z02076

good idea cleaning, inspecting deck & components, greasing spindles etc.

Thanks everyone! I took the deck off this weekend and was able to determine what I think the issue was. The tensioner pulley belt guide was really loose, so even though the belt was ran correctly, it wasn’t the strongest tension so the blade were able to spin but not peak. The mower has had a full tune up, cleaning, and new blades and cuts like new. Hoping to get a few good year out of it. Bought it for $300 and put about $150 into it. Not a bad deal for how great it runs.

:thumbsup: Sounds like a good score..