Need some help with BX2200 MMM creating "circles"

[sam24and48]

Long time lurker, first time poster so hopefully the pictures attach. I am having some issues with getting a lot of circles in the yard and it almost seems like the deck has to much play and as the tractor hits ruts the deck burns in on the far left blade and then the far right as it sways if that makes any sense. 2 mows ago after I noticed this for the first time I went through and leveled the deck with a blade leveling tool. I also did this for the first time at the beginning of the year and the cuts were pristine and level, no circles at all.

The only other thing that I changed at the beginning of the season when I leveled everything was some c type washers the previous owner put in. He had them inserted at the bottom of the spring which compressed the spring quite a bit. If I remember correctly there was no play in it at all. Could those springs be worn out from being compressed for who knows how long? I've had this unit for 2 years and I think it's a 2001 or 2002 bx2200.

I also was running slow to try and keep it from doing this but it didn't seem to change anything. Thanks for the help and guidance in advance!

 

[85Hokie]

question - what is the "size" of these swirl marks? Are they blade diameter or something smaller, hard to tell in the pictures due to lack of scale.

Have you taken that blade off and looked at it straight across?

Try and move THAT blade to the center position and see if it still does the pattern


One thing I do notice right off the bat - you deck seems to be sitting "low" - the guide wheel are tucked up rather high, thus making the blades sit a bit lower.

When you cut - do these wheels roll along the grass? Or hit every now and again?

When you leveled the deck ...... the front is about 1/4" lower than the rear - yes?

What height are you "cutting" to? is that fescue? (whatever it is - looks great btw)

I saw this happen before - but that was an easy fix..... the athletic director at our school hit a shot put with a blade ..... talk about a few swirl marks!!!

 

[sam24and48]

The marks seem to be a couple inches shorter than the blade. I have not pulled the deck to inspect the blades yet as it seemed like it wasn't just one blade doing it. It appeared to me that either outside blade was doing it almost offset as i went if that makes sense.

So the deck is set to 3.5 but in real life that is measuring about 2.75 from concrete to the blade when leveling it. The wheels this last time i mowed were rolling as i went, not necessarily supporting the deck but seemed to have enough resistance from the grass to roll if that makes sense. I paid attention to that as someone mentioned to me that maybe they had to much slop (didn't seem to).

Yes I leveled the front a 1/4 in lower as well.

The pictures i have the height would have been about 2.25in as I had the deck set to 3.0 The last two times I mowed I had it set to 3.5 and I mowed a different direction and didn't have as many circles. The pictures above though with the huge amount of them is where i'm hitting rutts in the yard from where it washed out some when planting last year. I did my best to fill them in with soil after but it still is a very bumpy ride if you are moving with any speed.

Yes it is turf type tall fescue, I have a local guy that helps me with our lawn supplies and the seed when we planted. He studied turf management and worked at a golf course for a decade or so before doing consulting and supply sales. So I can't take all the credit, but with his help we did it all ourselves with some rental equipment. Last spring was rough but we have put a lot of work into it and it looks 100x better than I would have imagined even at only a year and a half old.

 

[85Hokie]

I think the next step would be to look at the blades
Are they high lift blades? Mulching blades?

Another suggestion - take the pins out of each scalping wheel rod and lower them equally - leave ONE hole showing above the holder...... allow grass to grow out to that level (bet it has already) and then allow the wheels to hit the ground - thus the wheel follow the contour of the yard RATHER than the a tire dipping into a hole - cut the grass and see if anything changes. I agree that a pothole throws the deck down, with the wheels riding the soil - this should stop that from happening. Curious if this makes a difference - I believe it will.

 

[BAP]

Are you running the tractor at the rated PTO RPMs? If you are running it less than the rated RPMs, the mower won’t cut as well.

 

[dirtydeed]

I'd suggest to first tighten those rebound springs on the deck a bit. You may be experiencing to much "bounce" in the deck.

Second, crank up the leveling rods (front bracket) to raise the deck to the height which corresponds to the deck height indicator.

 

[85Hokie]

Sam

I just had a conversation with the local Co-op guy who does grass in 12 counties here in VA - I told him the entire story, he mentioned the bearings in the deck and see if there are any "cracks" in the deck that would create a "bounce"

I am still puzzled at the size of the swirls - if less than the cutting diameter how is that making those marks.

My first thought was something had been wrapped around the blade..... piece of landscape fabric or something, but I am sure that is not the case. But all those "circles" look like the blade is scalping rather than just pushing over the grass.

I would pull the deck and check to see if this a mechanical problem or a height problem or a speed problem.

 

[Tornado]

Yes just from what you can see in the pictures it would strongly suggest the blades are going up and down under the deck. Inspecting the circle's it is creating would tell a lot, as its hard to see in the picture what is actually in the circles, though they are visible. Is that grass being cut lower than the surrounding grass? Pushed down? Its hard to tell in the picture. But it almost looks like you are stopping every couple feet, but im sure youre not. The blades have to be moving up and down. I think this should be easy to track down with visible inspection under the deck. Look at the blades, check the spindles, check for play in the pulley and bearings. See if you can push and pull the blade up and down. Make sure blades are straight of course, and make sure RPM's are staying consistent while mowing. Its clear I think that to creat these circles something is alternating as you are mowing. RPM is going going up and down a lot, or the blade is moving up and down, something.

 

[aaluck]

It also appears that the ground is very unlevel. Maybe just the photo but that will cause this issue as well.

Is this occurring throughout the yard or in particular spots? Could be the blade moving up/down or the ground moving up/down. If it is everywhere probably the blade. If no probably ground.

The fact that these circles are so perfect I'm leaning to ground. But I guess you would have noticed this before now so very interesting. But as stated by @Tornado looks like you are stopping and lowering the unit every few feet.

 

[lugbolt]

mine makes circles if I stop, though not at any different cut height, if I stop, it will leave a circle of clippings (sorta like dust) and drives me nuts (mulching kit)--keep moving, cuts perfect

the only way that can happen is if the blades is moving, which might be from the deck bouncing, or dead bearings, loose pulley hardware, etc, maybe possible bent blade--and you can adjust the deck so it cuts level with a bent blade, although when you stop you will see imperfections in the cut

1/4 down pitch is a myth, should be zero. Only reason 1/4 down means anything is that it takes less power for the blade to cut with more pitch. Zero pitch increases the amount of power it takes to cut but the cut quality is considerably better

how are you leveling the deck? A tape measure on the outside of the shell ain't cutting it. I use a JD level gauge, on the blade--only way to do it. Also have an Oregon (I think) steel gauge and I like it but it's not yellow and doesn't stand out in the bottom drawer of the tool box, thus the deere gauge is the one I subconsciously grab most of the time

when measuring the pitch, you will turn one of the side blades so that is pointing fore and aft, measure the back, record that measurment. Then turn the center blade so it is facing fore and aft, measure the front of it. Subtract the difference and that is your pitch. Seen lots of guys measure one blade and adjust from there, it is much more accurate to measure the way I described--and cuts a LOT better. I learned this by doing it the wrong way for years and years, then tried it another way (my way) and bam--lots of happy customers. Lot of mowers come already set up from the factory with 1/8-1/4 pitch and it works fine, but I like perfection--particularly for certain customers who are picky and/or have nice grass like you do.

 

[ipz2222]

lower your deck wheels

 

[RCW]

That is a suspended mower deck; the anti-scalp wheels are not intended to carry the weight of the deck.

I keep my wheels at a similar height, but have never seen those types of swirls on a bumpy lawn.

That said, my grass is nowhere near as nice as that.....

Foolish question, but are the blades upside down? Not being a smart aleck; sometimes things happen. I bought a tractor once that had the blades upside down....

I agree with the others that something is shifting/bouncing while mowing.....

Is it possible to have someone else run and check to see what’s moving up/down? (Without getting too close to the moving parts)

 

[armylifer]

There is one other thing that you could check. If you have not sharpened the blades and there is a buildup of grass that is blunting the cutting edges of the blades, that could cause the swirls in the grass. I have experienced this on occasion, especially near the end of the cutting season. I suggest removing the blades and clean/sharpen them with a file. I used to use a grinder to sharpen but I have found that a file does a much better job.

 

[BAP]

Even though it is a suspended deck, I would lower your deck wheels so that it is almost riding on them when setting them on pavement. Mow one time that way and see if the circles go away. If they do, then you know that it is the deck bouncing and getting too low causing the issue.

 

[RCW]

Even though it is a suspended deck, I would lower your deck wheels so that it is almost riding on them when setting them on pavement. Mow one time that way and see if the circles go away.

I'm beginning to think this is worth a shot.

Not the way they're supposed to work, but trying one-time might help troubleshoot.

I wouldn't make any tight turns with the wheels way down, lest a spindle or bracket get bent if they hang up on somepin'...

 

[lugbolt]

good timing

Had to run to a customer's house complaining that his brand new kubota don't cut worth a flip

I get there and he's got the height adjusting knob at 1.5 (lowest setting) and basically cutting dirt

higher cut looks better, lower gives you more reasons to affect cut quality

So I set his height cam to 3 and told him to go cut the backyard. 3 passes, he comes back and hands me $20 and says thanks for the lesson.

worth mentioning

 

[whitetiger]

econd, crank up the leveling rods (front bracket) to raise the deck to the height which corresponds to the deck height indicator.

The Height Indicator is just a reference number, it is not meant to be Inches. I would like to see it labeled alphabetical to avoid confusion.

 

[GreensvilleJay]

I'd wait until the grass is high, then make a few passes at the highest setting. move over 2-3 'widths', then lower height one notch/number/letter/click... cut 2-3 more passes. do it again. This way you can SEE what happens, the lower you cut. Hard to see but do the 'circles' ONLY happen to ONE blade?

Curious though, as you've cut many times before and this 'just started happening' 2-3 cuts ago ? That would indicate 'something' happened then. Maybe you lowered the deck or something ?

Good thing is it looks like you have LOTS of grass to experiment on !!

 

[leveraddict]

Edit.....need coffee first!

My neighbors lawn tractor makes circles also. We found the end of the blade was split! They cut dirt not grass in their yard! They also hit every rock and root! Check the blades!

 

[rogerwh0825]

I'll add one more thought and hope you are not offended. I've done worse. My MMM has thick washers that go on the spindle above the blade. Is it possible one of these got left off allowing the spindle to travel up and down just a bit?