Export thread

New owner member of a gravely 48" zt HD . Just bought the mower today, cut my mowing time in half. Hope to have many more trouble free years! I have just over a acre, machine never bogged down once . Typical wife, wanted me to settle for the zt 42". But I was finally able to convience her that this is the model that would suite ourn needs the beat

I can say that is a nice mower because i have the same exact one :biggrin: Here lately though i have been trying to quiet down some rattling going on around the deck area when the blades are on and the engine is at full speed. At first i thought it was the anti scalp wheels on the deck so i tightened them all down except the one underneath the deck but that didnt fix it. Everything seems tight so i havent a clue where the noise is coming from but its loud enough to hear when im mowing. I got just over 10 hours on mine so far.

I have a similar noise. I believe it's the belt tensioner. It sounds like the tensioner spring is hitting the deck. I prolly put some sea deck I have around the house to place in between the deck and spring. See if it helps.

Couple photos.




Should work well for my little yard.

Looks nice and clean! Did you get the Kawasaki engine or the Brigs? I think i found that spring you spoke of, i noticed it has left a spot underneath it on the deck where its been rubbing so i put something there to see if that will quiet the noise down.

I have the 23 kawi, I hope it solves the noise for u. I'll start investigating my noise . Only 2 hours on the mower, 1st cu with it.

I figured out my little rattle noise was the belt tensioner spring hitting the deck.
I put a piece if seadeck (boat deck foam) on the deck and stopped the noise. Hope this helps others!


Used the mower for the 2nd time. Cut my front yard in 30-40 min, 2.6hrs on the mower. I'm really impressed with the mower. I can not imagine what a full commercial mower is capable of, I'm thoroughly pleased with my new mower. I may actually mow my yard once a week now and not dread mowing.

Yes, thats the same black spring that I put something under it, next time I mow soon I will see if it has helped or not. Theres no doubt, its a good machine, built to last. To be honest though, I am still learning the zero turn thing, trying to not tear up the grass when I turn and during zero turns. One thing that makes it harder for me to gauge when to move the leavers back into reverse is there isnt much feel for a neutral point if you know what i mean. I guess I just need to get used to stopping almost completely and then do the turn or something. Ive watched a few youtube videos on the subject as well. I noticed the tires on the mower seem very sticky as well, much better than the old sears I had before.

sk11venge said:

Yes, thats the same black spring that I put something under it, next time I mow soon I will see if it has helped or not. Theres no doubt, its a good machine, built to last. To be honest though, I am still learning the zero turn thing, trying to not tear up the grass when I turn and during zero turns. One thing that makes it harder for me to gauge when to move the leavers back into reverse is there isnt much feel for a neutral point if you know what i mean. I guess I just need to get used to stopping almost completely and then do the turn or something. Ive watched a few youtube videos on the subject as well. I noticed the tires on the mower seem very sticky as well, much better than the old sears I had before.

Click to expand...

It took me two seasons to learn how to make a zero turn without causing divets. One of the easiest ways is to make what is called the Y turn. Just remember to keep both back tires moving. When the inside tire stops moving during a turn that is what causes the divet. If you stop at the end and start backing up a little before pulling one lever backwards further. Both wheels will be moving then and you can spin around without damaging the turf.

I have the same rattle on my zthd 52, do you think it means the spring needs more tension?

It could possibly, but it's suppose to have a certain amount of play. Believe it's 12-14" from spring attachment to attachment. Not positive.

I bought a Gravely ZT HD 48" on May 25th(2017). I have less than 50 hours on this mower and I've already broken two hydro idler tension springs. I had unit towed to dealer the first time. They replaced the spring. A week later this spring broke again. me and two other guys got unit onto my trailer and I made trip to dealer again. The dealership informed me that Gravely had told them this spring is defective. I have another spring on unit but I'm afraid to take mower out because another spring failure would result in another towing expense.

I spoke to Ariens customer service after providing them with my mower model and serial number. They are aware of problem and say they are waiting on spring manufacturer to send them new, improved springs. I was told this "might" happen in 2-4 weeks. I don't know what other Gravely zero turn models may have this problem. The model # of my ower is 991162.

I emailed Gravely with detailed account of my problem and haven't heard back from them yet.

For now I have to use my Gravely 48" walk behind mower(2015 model 988152) while my riding mower, less than six weeks old, sits in my garage carport.

Take your old broken spring to an engineering supply store or specialist spring maker.
One of them will have a suitable replacement or know where to get one from.
Buy a couple then go mow.
You might need to make a spring puller from a length of heavy wire if the tensioner arm does not have a hole for a breaker bar.

I emailed Gravely and received a reply back that new hydro idler springs will be shipped out to deales in three weeks. Add another week, they said, before springs are actually available to customers who need them. The end result is my riding mower will now sit in my carport for a month while I'm out two lost work days and $335 due to towing and repair expense from the first spring failure. I asked Gravely about some sort of compensation for my expense due to their defective spring...and received no reply back on that.

I also called and left a voice message for a Gravely regional manager(southeast) and haven't heard back from him.

I can say with absolute certainty that this riding mower will be the last Gravely product I ever buy. It''ll take me at least two years to pay the riding mower off and that cannot come soon enough.

Broke my first one Sunday afternoon. Loaded it up and took it to the dealer today. I was in and out in 10 minutes, fixed it on the trailer. Great dealer. Would have done it myself but they said it was pretty hard to get on. Two guys put it on, but I believe I'll just pick up a spring and do it myself next time. I'm fairly sure there will be a next time. I've only got 20 hours on mine.

Hi all! Stumbled upon this forum 'googling' for this exact issue. Spring broke with just over 6 hours on my 6 month old ZTHD 48". I learned that the "old" part number for the spring is 08300505, and the NEW updated spring is 08300711. The new spring appears to be the exact same spring, but about 1" longer. I have installed the new spring, and my belt flops around like crazy... I'm not expecting it to last, I never looked at the belt before, and I haven't mowed yet though, maybe they always flopped. Gravely CS also told me that I should bring my mower in for a "Engine Adjustment" Whatever that means... My dealer had no clue what she was talking about. When I responded to them, this was the exact response:

"It is recommended if the spring has broken to have the replacement spring and adjustment done at the same time. If you continue to use your machine we recommend that when the mower is on to always run it at full throttle to reduce vibration on the machine"

Anywho, I'll see how my mowing goes now and keep this thread updated.

As a side note, if you're ever in a bind because the spring broke, one of the 2 gold springs from the deck work like a charm in a pinch if you have a small tow strap (and a helper or a fence post/tree) to stretch it.

As a second side note: I griped about not being able to see my fuel level in the "window", apparently they are aware of the issue and their "engineering department is aware and looking for other options for the fuel gauge window material" :|

I didn't contact Gravely, just called the dealer and they said bring it on in. I didn't even sign anything when they fixed it. They just grabbed the spring and stuck it on there. I think he looked at the number on the mower, but he didn't write it down. I guess he has a good memory. Nobody mentioned any kind of adjustment, and I don't have a clue what Gravely would want to have adjusted on the engine at such low hours.

packmule said:

I bought a Gravely ZT HD 48" on May 25th(2017). I have less than 50 hours on this mower and I've already broken two hydro idler tension springs. I had unit towed to dealer the first time. They replaced the spring. A week later this spring broke again. me and two other guys got unit onto my trailer and I made trip to dealer again. The dealership informed me that Gravely had told them this spring is defective. I have another spring on unit but I'm afraid to take mower out because another spring failure would result in another towing expense.

I spoke to Ariens customer service after providing them with my mower model and serial number. They are aware of problem and say they are waiting on spring manufacturer to send them new, improved springs. I was told this "might" happen in 2-4 weeks. I don't know what other Gravely zero turn models may have this problem. The model # of my ower is 991162.

I emailed Gravely with detailed account of my problem and haven't heard back from them yet.

For now I have to use my Gravely 48" walk behind mower(2015 model 988152) while my riding mower, less than six weeks old, sits in my garage carport.

Click to expand...

Just a suggestion, maybe order a spring online (if available) from Ariens or Gravely. Good luck, my Gravely is 11 years old and no problems with springs at all. Only replaced pump drive belt after 10 years.