Grass build up

[Mtsoxfan]

I have a Cub Cadet zero turn, but I'm sure many mowers have the same issue. As seen in pictures, there are openings in the deck around spindles that allow cut grass into pully area. No exaggeration, I just filled a 5 gallon bucket, with compressed grass. It's a pain in the butt using a blower or manually taking off guards. Is there a reason for these holes? My only guess is to allow air escape for high lift blades. If they were plugged, wouldn't the grass keep getting mulched?
Is there a reason I shouldn't find a way to plug holes? Has anyone tried this?

 

[Runner]

What model is it? I have a CC ZTR (Ultima ZTXS 5 54), but don't have holes like that on mine.

Have you always owned the machine? I wonder if the spindles have been replaced and there are parts missing, or maybe wrong spindles?

Mine gets a TON of grass built up on top of the deck, but the belt guards are open on the sides, so it's pretty easy to blow it off with the air gun.

 

[JBF43]

I have the cc ztr50, uses the 50" cut deck and it has those same holes through the deck by the spindles. I have also wondered about the purpose of the holes. Mine loaded up with grass so badly that I had to remove the guards to clean it all out. After several times doing this I got tired of messing with the guards so I have been running it without them. I still get just as much grass buildup on top of the deck, but it is easier to clean out. I have wondered if maybe those holes are vents of some type to assist in air flow for high-lift blade operation. I have problems getting a good, clean cut. New and sharp blades, clean deck underneath. Deck is level and all blade ends are the same distance off of the ground, blades are the right length and installed properly, and when you sit in front of the deck with the mower raised and position the blades so they are all in the same position, (like clock hands in the 9 an 3 positions,) there is a good 2-3" overlap of the blade paths. Yet when I try mowing and get into bahia, the center and right side blades tend to leave a lot of uncut grass. One reason for asking this question is that when I start out with freshly sharpened blades, (30* angle) and a totally clean deck, both top and bottom, it seems to cut normally. But after mowing for a while and the deck getting covered in cut grass with no grass stuck up under the deck, (coming up through those holes?), that's when the problem becomes most noticeable. I always mow when the grass is dry. Just wondering if those holes are some kind of vent for air flow. I guess the next time I mow, I will make an effort every so often to clean off the top of the deck and see if this cures the problem. Didn't mean to hijack this thread, but the OP got me started when he asked the same question I had about the holes in the deck.

 

[350c]

I have the cc ztr50, uses the 50" cut deck and it has those same holes through the deck by the spindles. I have also wondered about the purpose of the holes. Mine loaded up with grass so badly that I had to remove the guards to clean it all out. After several times doing this I got tired of messing with the guards so I have been running it without them. I still get just as much grass buildup on top of the deck, but it is easier to clean out. I have wondered if maybe those holes are vents of some type to assist in air flow for high-lift blade operation. I have problems getting a good, clean cut. New and sharp blades, clean deck underneath. Deck is level and all blade ends are the same distance off of the ground, blades are the right length and installed properly, and when you sit in front of the deck with the mower raised and position the blades so they are all in the same position, (like clock hands in the 9 an 3 positions,) there is a good 2-3" overlap of the blade paths. Yet when I try mowing and get into bahia, the center and right side blades tend to leave a lot of uncut grass. One reason for asking this question is that when I start out with freshly sharpened blades, (30* angle) and a totally clean deck, both top and bottom, it seems to cut normally. But after mowing for a while and the deck getting covered in cut grass with no grass stuck up under the deck, (coming up through those holes?), that's when the problem becomes most noticeable. I always mow when the grass is dry. Just wondering if those holes are some kind of vent for air flow. I guess the next time I mow, I will make an effort every so often to clean off the top of the deck and see if this cures the problem. Didn't mean to hijack this thread, but the OP got me started when he asked the same question I had about the holes in the deck.

I have the same issue with the 54" deck on the XTS54 Ultima--even with new blades, there is a strip left where the grass is not cut as low, not high but enough to be noticeable. Mine is a steering wheel model (due to shoulder problems), another neighbor has an older steering wheel model while another neighbor has the lap bar model, and we all have the same issue with the higher strip. Pleased with the machine overall, but disappointed in the look of the cut after finished. Undoubtedly CC needs to do some redesigning of their decks or their blades--they're way too expensive to leave those unsightly strips. I'm going to look into the Exmark z-turn with steering wheel.

 

[Fields_mj]

I generally hate having covers over things. My Kubota F series has 2 covers on the deck that prevent access to the belts and spindles (except for the cutouts for the grease zerks). I leave that cover in place for this very reason.

 

[RjCorazza]

I generally hate having covers over things. My Kubota F series has 2 covers on the deck that prevent access to the belts and spindles (except for the cutouts for the grease zerks). I leave that cover in place for this very reason.

The first thing I did is remove the belt covers on my ZD mowers. Grass packs up in there, and it's a pain to remove them each time I blow the deck off (at least once each day). No testing, but I suspect the spindles, pulleys and belt get hotter with the covers on also. My anecdotal "evidence" is that after 2100 hours on one, and 1800 hours on the other, I'm still on the original spindles and belts!

 

[Fields_mj]

I take the covers off every spring to make sure there's no build up. So far, there has been none with the exception of what comes in around the grease zerks. In the early 90s I was mowing 10-15 acres a day with an F2100. We put a little over 1000 hrs a year on the machines. No issues with belts wearing out, but spent the last 10 min and first 10 min every day doing general maintenance, checking fluids, screens, and fueling the machine up. Today, I only mow an acre and a half once a week. I generally knock the grass off the deck after I mow. Other than that, I grease the machine about twice a year. The machine is overkill, but I want the job done relatively quickly and I found it for a pretty good price on the used market.

 

[Runner]

I have the same issue with the 54" deck on the XTS54 Ultima--even with new blades, there is a strip left where the grass is not cut as low, not high but enough to be noticeable. Mine is a steering wheel model (due to shoulder problems), another neighbor has an older steering wheel model while another neighbor has the lap bar model, and we all have the same issue with the higher strip. Pleased with the machine overall, but disappointed in the look of the cut after finished. Undoubtedly CC needs to do some redesigning of their decks or their blades--they're way too expensive to leave those unsightly strips. I'm going to look into the Exmark z-turn with steering wheel.

I wasn't aware anyone but CC made steering wheel ZTR's now. I don't see it on the Exmark web site. Do you have link for this machine?

My CC Ultima ZTXS5 54 cuts fine and does not leave any strips.

 

[JBF43]

Inquire and ye shall learn: Ok so I googled it and AI says this:
AI Overview

The openings near the spindles on a Cub Cadet ZTR 50 mower deck are designed to allow air to flow through, which helps create a vacuum for better grass lift and a more even cut, according to a forum discussion on Only Cub Cadets. This airflow is crucial for the mower's cutting performance.

So, to answer the question for the OP, should I close up these holes? I think the answer is no, according to what AI says. Now that raises another question: why do some of their decks have holes and others don't? Also, on the decks without the holes, what is the quality of the cut, does it leave any uncut or unevenly cut grass?
My mower was purchased new a lot of years ago from Home Depot, and when I first got it, the cut was perfect. It has been a great machine, just now coming on 350 hours, and this since I think 2009 or so. I have replaced the belts, blades some of the tires, touched up the paint, and just recently recovered the seat. All of these things are time/age-related as opposed to high-hour usage, as I have several mowers to work with.
I will try, as I mentioned earlier, to keep the top of the mower deck cleaned off several times while mowing acreage to see if this improves the cut. I have read on lawn mower forums that this problem is very common on many types/ brands of mowers. The experts there usually blame unlevel decks, belt slippage, badly worn pulleys, improper use or installation of blades or damaged/ dull blades, bad spindle bearings causing blade tip speed slow down, etc. All of these things I have checked for on my mower. Some of the experts there say that some mower decks are NOT made to be used with HIGH LIFT blades. I do not remember what the original blades that came on my mower were. But as best as I can remember, I don't think they had the high back 'wings' on the back of the blades. Has anyone else come across this as a problem on your machine? I have been trying to find a Cub Cadet original blade part number and get a set of those blades to try. So far no luck.

 

[350c]

I wasn't aware anyone but CC made steering wheel ZTR's now. I don't see it on the Exmark web site. Do you have link for this machine?

My CC Ultima ZTXS5 54 cuts fine and does not leave any strips.

I had seen an Exmark Quest S with steering wheel on the internet. Further research today shows they made it for a couple of years, ~2014-2016, but stopped producing. Supposedly CC has patent and no one can produce with steering wheel. ??