Cub Cadet 54" Deck Poor Cutting Performance

[FlyingDutchman]

I have an old 1641 Cub cadet. It has a 20hp briggs repower and a 54" deck. It has very poor cutting performance and plugs up constantly. I have a system of driving up on ramps every half hour of mowing and cleaning it out. I have newer high lift blades on it. It doesn't start to be effective until the late fall when the grass is dry and tough and then it works okay. The chute is also gone. Seems to have enough power to run it. Just terrible performance.

I'm debating getting a smaller used 48" deck and hoping that this is just a crappy design. The deck is rusty and in crummy shape anyway.

I think that this mower wasn't designed for a 54" too and I may not have enough power potentially. But the repower is more than the 16 it came with.

 

[alleyyooper]

If the under side of the mower deck is all rusty and pitted the early juicy/wet spring grass with stick to it and like wet snow keep sticking.

Is best to clean the under side of thr deck and spray some cheap rust proofing paint under there to get some slip.
20 Hp should be plenty to run a 54" deck.

Have a 9HP engine that works a 42" deck just fine.

Al

 

[FlyingDutchman]

I angle ground and painted under the deck last year but no change. It is quite pitted. And there are a couple holes rusted in it too which probably don't help.

 

[boltonranger]

Grass cutting height matters. A lot.
If you’re cutting very tall grass, that is if you’re cutting off more than a third of the height of the grass blades... you’ll have issues with discharge. Especially if the grass isn’t bone dry. There are spray on products that act like Teflon but it won’t work if you’re cutting grass that’s too tall.
One thing you can try is cutting on the highest setting first and then a notch lower on the second go round.
Another thought- is your blade belt worn or loose? That will cause the same problem. You should not be able to move the blades by hand with the lever engaged. Engine off/ plug disconnected of course.

 

[FlyingDutchman]

The drive belt was very worn, tand actually broke at the end of last year. I replaced it and it helped a lot. The deck belt was fine. I also sharpened the blades and painted the deck again and it seems to perform okay.

 

[boltonranger]

Help me understand - did you find improvement before you began this thread and were just curious as to why you had earlier issues? Or did you clean and repaint since the beginning of May?

 

[FlyingDutchman]

Cutting performance had been getting worse and worse over the last few years, I was trying to justify moving to a smaller deck with a different design which I would purchase, used, at the same place as I'd get a belt. That's why I made the thread, hoping the smaller deck would solve the issue. The belt new cost almost as much as a used deck, and the different sizwd decks needed different belt lengths.

So when i finally went to get a belt/Maybe a deck, the width of the belts broken old vs new was pretty extreme. The guys at the Cub dealership were quite sure that the belt would solve the issue. The belt may have been slipping under load but reached full speed with no load, preventing proper lift on the blades during normal cutting with a load. Before it broke anyway.

In addition to the new drive belt I painted the deck and sharpened the blades and performance is good or on par with other mowers I've used. Boltonranger you were dead on with your prognosis of the bad belt.

 

[boltonranger]

Well, I’ve been there. It’s amazing how different a machine will perform when it has a bad belt, bearing etc. sometimes like night and day.

 

[blades]

some of the decks out there just are not worth a squat in heavy vegetation. the decks from late 60's to early 70's from simplicity were among the best designed. 8hp gear drive 728 mower could plow through just about anything in 1'st gear. set high of course. these current offerings lose so much hp to the hydro drive systems it is a shame ( course if some these motors were rated the same way they were years ago that 20hp would likely only be 10hp if that)

 

[Huskybill]

I can’t let the grass get too high if I’m looking for a good looking lawn.