Tracks between blades

[bertsmobile1]

blades rotate so they can not leave strait lines
Those troughs are your gauge / deck / anti scalp wheels running on the ground because they are set too low for the cut height.
Mparr suggested that way back in post #4

 

[sgkent]

I can't tell you how to fix or what causes it but my eyes see scalp marks on the outside blades where they are lower than the center, and the center row has edges between blades. One can see each cut of the outer blades where it scalped. How worn are the blades? What are the outside cutting edges like on the center blade?

 

[Ips]

Are you mowing in damp conditions?
Are your deck wheels in contact with the ground? The deck should not be supported by the deck wheels.
Do you have the correct blades?
Is your deck leveled and pitched correctly? Check level and pitch as described in your manual.

Yes the grass is damp, its autumn going on winter downunder, but this was not a problem last winter. The blades are new and supplied by the JD dealer.

 

[Ips]

I can't tell you how to fix or what causes it but my eyes see scalp marks on the outside blades where they are lower than the center, and the center row has edges between blades. One can see each cut of the outer blades where it scalped. How worn are the blades? What are the outside cutting edges like on the center blade?

Three brand new blades previous cut all in good condition and level.

 

[bertsmobile1]

So are you on the East Coast where we have had 1.5 to 4 years annual rainfall in the first 4 months of this year ?
Those look like wheel ruts to me caused by he gauge wheels

The ground right now is really soft & springy so the mower itself sits lower in the grass
Thus the deck wheels that used to ne 1/2" above ground level are now 1/2 below grounfd level.

Before the rains came , even if the wheels were running along the ground the ground would have been hard enough for the wheels not to be rutting the lawn
However now the ground is very soft so they leave ruts in the lawn
1) move the deck wheels to their highest position & see if it leaves the ruts in the grass
or
Cut with thee deck in the highest position and see if they vanish
2) measure the height of the deck & the gauge wheels from the ground
In all height settings the gauge wheels must he 1/2" minimum above the ground

Do a single cut
Get off & measure the distance between the lines
Then measure the distance between the wheels .

Right now my 24" Victa push mower leaves tracks in the grass
The landlord is leaving his car in the street because it gets bogged if he tries to go up his drive
We have a mower stuck in the creek , again bogged and the tractor started to slide when we tried to recover it .
Some of my commercial customers are cutting the residential with line trimmers because their mowers are chewing up the ground

 

[StarTech]

Also would help to check the spindle themselves for bearing wear. This can cause the blades to tilt causing a cut like this from belt tension. It does look like the two outer blades have their tips meeting the center blade lower. Just a thought.

But as said by Bert wet soggy lawn can be a problem to at any time.

 

[Ips]

You may have solved the prob. I'm actually in SA. The area that this is a problem is primay school ovals with sprinkler systems that aren't manged properly. This seems to be most noticeable where the sprinklers overwater areas and the ground is soft. Ill recheck the widths when I'm back there next time and let you know.
The scalp wheels are set to the height specified on the deck but may not be high enough on soft ground.
Thanks to all for your help
Cj

 

[MParr]

Yep, wet lawn, mowing too low and deck wheels set too low.
Raise the deck wheels. Set the deck wheels according to the manual. You may have to experiment with those settings. Many times, you will have to be one notch higher than what’s called for in the manual.
Raise the deck. Make sure the actual cutting height matches your deck selector height. A lot of times the two do not match. For example, putting the deck at the selected height will actually have you mowing lower than you should be. Once you determine that, you can put the height selector exactly where you want it.

 

[Ips]

I think I may have mislead people calling them tram tracks but it was the best way I could think of to descibe, the lines they are not depressions they are uncut lines between the blades.
Sorry for the confusion

 

[StarTech]

I think I may have mislead people calling them tram tracks but it was the best way I could think of to descibe, the lines they are not depressions they are uncut lines between the blades.
Sorry for the confusion

Then more likely to be blade tip wear.