Gravely ZTXL 48 cut issues

[Eddie S]

Hello folks.

First off, a search just led me to one thread about a mohawk cut, but the OP suggested this is a known issue with no fix. But I think I saw something on youtube that addressed this, so...

I got my ZTXL 48 last spring, first one delivered to my area. Immediately I noticed I had to make 2-3 passes to get sparse/thinner areas cut. Thick, lush areas did better, as long as I wasn't cutting more than a few inches off; if more, then it too needed to be cut several times. I put the mulch kit on, and it didn't change anything.

Early last year, before I bought the Gravely, I saw a video where an owner of a Gravely zero turn (think it was a Gravely, and not sure which model) contacted his dealer about this, and Gravely responded with a kit that changed a pulley size, added an idler pulley, and new belt. If I remember right, it was an issue of blade speed being too high, causing thinner or longer grass to blow over.

I cannot find that video anywhere, or any verification that this was the solution.

I've contacted my dealer, and am waiting for a response. If this is a known issue, other than the one Ariens post I saw, are there links specific to Gravely ZT, ZTX or ZTXL models (and Ariens homeowner models) that talk about this?

Thank you for any help.
-Eddie

 

[bertsmobile1]

First,
If you are mulching then you should never ever be cutting more than 2" off the grass & that would have to be on the highest setting or you will both overwhelm the deck and produr more clippings than can be accomodated by the remaining grass .
Even worse is the higher the deck, the worse the mulching action is because of the air flow under the deck, unless you have bought a dedicated mulch only deck .
Usually not cutting fine grass is because the blade speed is too slow or it is the wrong deck & blade combo for the grass.
There is a reason why fairways are cut with reel mowers and the rough shoulders are cut with a rotary.
They are different grasses.
Rotary mowers work best with stiff thick grass like buffalo or rye
Reels work best with thin fine leafed grasses like couch

 

[Eddie S]

Thanks for the reply and the info.

I’ve been mowing the same properties for 40 years, part Bermuda, part St. Augustine, with MTD, AYP/HOP, Toro, and Honda HRC Commercial push mowers and an AYP/HOP-made Craftsman 42” garden tractor. The 42” has served for 25 years. None of these mowers ever had an issue cutting, whether discharging, bagging or mulching, drought years or heavy rain.

I also do field mowing with a Massey-Ferguson tractor with a 60” sidewinder. Again, no matter how tall the grass or weeds, I rarely have to go over an area a second time.

I purchased this 3-blade 48” Gravely to save time (on lawns, not field work), but going over areas 2 to 3 times is ridiculous. I live in the desert part of New Mexico, so lush lawns aren’t the norm. I’m wondering if this design isn’t well thought out, or if it just isn’t for the grasses I’m cutting.
Again, thanks for the reply.

 

[bertsmobile1]

It is just the wrong mower for your property .
Once upon a time , in a land far away , mower shop sales staff were old mower techs and retired lawn contractors
So you went away with the right mower for your needs.
Now days they are phychology majors who brain wash into believing that whatever mower they make the most profit on is the one you need.
Sounds like you just have the wrong combination of mower, deck & blades .
I see it happening almost daily with people coming to my gate to get "blade that work properly" cause the ones on their mower are leaving clumps, missing strips, missing the odd blades here or there , etc etc etc
Always comes down to them being sold the wrong mower & generally told a pile of BS by the sales staff.
I am not aware of any specific problems with Gravely decks.
However we get different specs down here as we allow a lot faster blade tip speed & imported mowers have to compete with the far superiour cut of blade discs with swing back blades .
Also almost any mower from 25 years ago will cut a lot better than it's modern counterpart because the profit level on ride ons has gone through the floor and thus they are nearly all build down to a price.
Add to that blade tip speeds are perpetually being decreased

 

[Eddie S]

Thanks bertsmobile. I assume you're Aus or NZ. I understand swing back blades are approved there for push mowers. My 60" sidewinder has swing back blades, which is so beneficial with unforeseen objects, but yes, our US lawn mowers don't allow those.

My issue is that I normally maintain about 3,000 RPM for the push/ride on mowers, so tip speeds are within accepted FPM limits; but common wisdom among brush hog/sidewinder users is, if you're not cutting well, decrease PTO gear speed (reducing tip speed), and increase ground speed. I can't attest to whether this wisdom works, but I've heard it works for tall grass/weeds that aren't getting cut.

I can't try this method with the Gravely, as the hydraulics are RPM dependent, so, decreasing overall RPM to decrease tip speed isn't an option. Hopefully, my dealer will find out something; if not, looks like I'll be selling the Gravely, and swapping out engines on my tried and true old Craftsman. Heck, I've replaced almost everything but the transaxle over the last 25 years...

 

[bertsmobile1]

Well I have jus finished mowing a 1 acre paddock that had 5' tall seeding spikes
and going fast is not an option .
I can not see that working but then I can not see your paddocks either
However when mowing the 500 odd acres of rough pasture we always found slower was better .
However we probably have totally different grasses as the paddocks are mostly Rye , Kangaroo, Wallaby , Paspalem, Kikuyu & Tussock with a little Lucerne & Clover
And of course we are mowing at 5" to 6" , more like headding than mowing.
Around the house I run the 2 stroke Victas at around 4000 rpm .

AFAIK the Grevely has a fabricated deck and as a rule they give a substantially poorer cut than pressed decks because they can not accomodate the extra volume at the discharge side without significant baffeling under the deck to control the air flow.

In theory the air flow sucks the grass up like a vacuum cleaner then the blade lop them off .
The only bar blade decks that give a really good cut are the ones with a big blade overlap & timed blades.