Grass isn't cut between the blades.

[Scotty xd]

Any closer and they will be slapping each other

IF you have sharpened the blades and Checked top and bottom of Spindles for nut and blade(s) tightness, Belts tight and in good condition, then check Blade length. If all of the above are ok then IDK. Try longer blades?

 

[Johner]

View attachment 68812View attachment 68812
Any closer and they will be slapping each other

I would suggest your losing lift with those blades. I can not prove that. Only thing I can say is check the front edge is lower then the back 3/8". Looks like the deck needs welding repair.

 

[ILENGINE]

Something else to check is the deck itself What I am referring to is some decks will have a flat plate that protrudes under the front of the deck to help act as a guide to direct the discharged grass, but will lay taller thicker grass down and not allow the blades to pick it back up. And seems to effect the center blade more than others but is some cases will cause a skip between the blades on two deck systems.

 

[MParr]

Has anyone mentioned the middle blade should be longer. I have a Snapper zero turn, cutting high weeds "dandelions" mostly, making the return cut darn near all the D's were still standing. Finally called factory, they said the mower deck needs to be 3/8" lower in the front. That fixed the problem.

That 3/8” higher in the rear doesn’t apply to all brands.
For the OP’s Gravely, all blades are to be 20.5” in length, 2.5”wide, 0.25” thick, and have a 5/8” center hole.

 

[cootertwo]

I've had a similar problem with my ZTX42 since new. The deck has no baffles, just plain open. Other decks with baffles don't seem to have this problem.

 

[flaing]

Is there a way to fix the problem of grass left uncut between the blades? It is particularly bad between the left and center blade. I removed the relatively new blades (installed about 2 months ago), and rotated them, L to C, C to R, R to L, and I get the same result...2 stripes of grass the entire length of my mowing, which means I have to mow over the same path a second time, but slightly moved to the side to make sure my blades cut the 2 stripes that are left between the 3 blades. The grass between the left and center blade is up to 12" wide, while the grass left between the center and right blades is about 2-4" wide. I have the ProMaster 260.

My 472 does that whenever I mow too fast in tall grass. I’ve always had to just go real slow and/or mow it twice. It doesn’t leave streaks when cutting 4-6” tall grass, And, it cuts better at around 3” setting. Just remember, a zero-turn is a finishing mower, not a bush hog. It’s not designed to make clean cuts in very tall grass.

 

[rhkraft]

The grass you are cutting doesn't seem that tall but try it on shorter grass first. If the stripe is still there, it appears that the center blade is not cutting, i.e., the center blade is not turning. You did say you replaced 3 blades, right? Is the center spindle stuck? Make sure the blade is engaged with the spindle shaft. It is possible to bolt on the blade without the blade being engaged to shaft in which case the spindle turns, but not the blade due to the grass resistance. On all mowers the blades are offset so they overlap the cut.

 

[sam.marrocco]

View attachment 68812View attachment 68812
Any closer and they will be slapping each other

Keep in mind that they are not always in that position. If that’s how they are synchronized, the when they’re both 90 degrees to that they will miss spots in the center if you go too fast.

 

[Chuckers]

The dealer told me he had done all he could do.

Try to find a more experienced tech that is independent of the brand.

I mean, he insinuated he fixed it, you showed him the problem still persists and he just shoved it off basically telling you he can't fix it when his story was different just moments before lol.

 

[Mezman]

Is there a way to fix the problem of grass left uncut between the blades? It is particularly bad between the left and center blade. I removed the relatively new blades (installed about 2 months ago), and rotated them, L to C, C to R, R to L, and I get the same result...2 stripes of grass the entire length of my mowing, which means I have to mow over the same path a second time, but slightly moved to the side to make sure my blades cut the 2 stripes that are left between the 3 blades. The grass between the left and center blade is up to 12" wide, while the grass left between the center and right blades is about 2-4" wide. I have the ProMaster 2

Is there a way to fix the problem of grass left uncut between the blades? It is particularly bad between the left and center blade. I removed the relatively new blades (installed about 2 months ago), and rotated them, L to C, C to R, R to L, and I get the same result...2 stripes of grass the entire length of my mowing, which means I have to mow over the same path a second time, but slightly moved to the side to make sure my blades cut the 2 stripes that are left between the 3 blades. The grass between the left and center blade is up to 12" wide, while the grass left between the center and right blades is about 2-4" wide. I have the ProMaster 260.

Check that your spindles are good. Pull off your belt and check to make sure there's no bearing noise and they free spin. I had one that would get hot after I mowed a few rows and slowed down that blade. So I thought dull blade or loose belt or that the hole in my old deck wasn't letting it create the suction it needed to lift the grass or something. Pulled my hair out for a couple seasons making sure I cut the grass before it got more than an inch or two otherwise I had to go over a lot of it twice. Check your spindles .