X758 Deck leveling problems solved

[roostershooter]

Picked my machine on Tuesday. The lift arms that attach to the rockshaft were replaced. Apparently the arms have been redesigned and thicker material used. This did not improve the quality of cut. Dealer says a smaller 48 inch deck would solve my problem. A $10,000 machine and can't get a decent cut. Makes me sick.

 

[buickanddeere]

If the rockshaft arms are not indexed the same. Adjusting the linkages will even the deck at only one height setting.

 

[roostershooter]

If the rockshaft arms are not indexed the same. Adjusting the linkages will even the deck at only one height setting.

They are indexed the same now.

 

[jonsstihl]

So what is the cut quality problem you are having because Mine is the same. my levers are not indexed the same and I suspect it is the rockshaft that is twisted but I am able to level my deck only one side is all the way down and the other side is almost all the way up. i mow my lawn at approx 2.75 inches but I have to set my deck height at 3.5 on the knob. and I can't use the quick leveling gauge that comes with my 15,000 dollar tractor.

other than the setting I have no real issues with the cut quality and I'm using a powerflow to bag the clippings.

 

[roostershooter]

So what is the cut quality problem you are having because Mine is the same. my levers are not indexed the same and I suspect it is the rockshaft that is twisted but I am able to level my deck only one side is all the way down and the other side is almost all the way up. i mow my lawn at approx 2.75 inches but I have to set my deck height at 3.5 on the knob. and I can't use the quick leveling gauge that comes with my 15,000 dollar tractor.

other than the setting I have no real issues with the cut quality and I'm using a powerflow to bag the clippings.

Get you one of these...John Deere Leveling Gauge for Mower Deck Blade Height - AM1397

My problem is that the deck level seems to change from the time I leave the garage to when I mow. I can level the deck, mow 5 minutes, check it again and one side will be off. The dealer said that I should consider a lighter weight deck. My neighbor has his yard mowed with an Exmark zero turn. That's not a light weight either. His yard looks ten times better than mine. The arms that attach to the rock shaft were replaced on my machine, tech said they were wearing a bit and had a slight bit of play in them. They are #21 and # 22 in this exploded view.

 

[beenthere]

Rooster...
So after mowing 5 minutes and then you find one side is off, what has to be adjusted to get it back to level again?
That should be a clue to what is changing during the 5 minutes of mowing...

Would you go through the steps that you take to level your deck for us? Maybe we can help solve the problem.. (don't think whoever it is at your dealer making the comment knows or cares about your problem).

 

[roostershooter]

Rooster...
So after mowing 5 minutes and then you find one side is off, what has to be adjusted to get it back to level again?
That should be a clue to what is changing during the 5 minutes of mowing...

Would you go through the steps that you take to level your deck for us? Maybe we can help solve the problem.. (don't think whoever it is at your dealer making the comment knows or cares about your problem).

I use the leveling tool referenced in post #25. To level the deck you adjust the leveling bolts #25 with the tool # 20.

Other than the deck, my biggest problem is this....I traded an x540 for this x750. The x750 only had 50 some hours on it and was only 1 year old. I traded with a guy in North Carolina and my dealer is not the selling dealer. That is an issue that I can't do anything about.

 

[beenthere]

So you also go through the following steps in order ?

1. check tire pressures to be near 15# in fronts and 8# in rears.
2. raise all four deck wheels high as they can go.
3. park on flat surface.
4. set deck height (say 3" ).
5. check that mower blade tips meet at the same height to eliminate a bent blade.
6. measure, with gauge, at the tips of outside blades and adjust both sides to the 3" via hanger bolts #25
7. measure center blade in front and back position to adjust the front draft so the leading tip is 1/4" lower than trailing tip.
8. set desired mowing height on height control.
9. lower deck wheels to as near 1/2" from flat surface (not touching).

Should then be good to go (if I didn't miss anything.. )

 

[roostershooter]

So you also go through the following steps in order ?

1. check tire pressures to be near 15# in fronts and 8# in rears.
2. raise all four deck wheels high as they can go.
3. park on flat surface.
4. set deck height (say 3" ).
5. check that mower blade tips meet at the same height to eliminate a bent blade.
6. measure, with gauge, at the tips of outside blades and adjust both sides to the 3" via hanger bolts #25
7. measure center blade in front and back position to adjust the front draft so the leading tip is 1/4" lower than trailing tip.
8. set desired mowing height on height control.
9. lower deck wheels to as near 1/2" from flat surface (not touching).

Should then be good to go (if I didn't miss anything.. )

Yes I do that initially. I do not go thru every step every single time. From what I have read, others need only adjust the deck on x700 series maybe once a year. So, to wrap all this up because I don't see much improvement with this mower deck, I doubt that I will buy another deck for this machine. I'll just use my push mower for the front yard and maybe look for a smaller rider to use at a later date. Thanks to all who posted.

 

[jonsstihl]

don't give up on your dealer yet. at that price point you shouldn't be mowing your lawn with another mower. the only thing I can think of that hasn't been talked about is that you may have a bent blade. when I got mine (one year old with 250 hrs.) the guy was using standard blades with a mulching kit and the blades were all bent to heck. he must have hit a rock that bent on of the mulching baffles which began to hit the blades.

 

[roostershooter]

No bent blades. That was one of the first things that I changed.

 

[jonsstihl]

I have one of those gauges and it works well but for the price this tractor is, I should be able to follow the instructions that came with it and level my deck the quick way instead of the long way especially because the powerflow attachment makes measuring the right side blade that much more difficult.

If your levers are level now you should be able to level the deck in the middle of the range of the adjustment bolts. I don't know what kind of locking feature deere has built into this adjustment but if the bolts are moving maybe the half moon blocks the bolt screws into are not holding the threads tight enough. Item 23 in the parts catalog you posted.

I had to change a locknut on my old x320 because the deck would not stay level.

 

[roostershooter]

Resurrecting an old thread with an issue for me that has never been resolved. My x750 mowed so bad that I resorted to using a walk behind on my front yard. I got tired of walking the front so I bought a Scag to mow with. Anyway, I bought a CTC loader for the x750 and while I had it apart to install the THRV I saw what may very well be my problem.

As I've said before in this thread the levelness of the deck seems to change on the fly. The pics attached show the deck cam adjuster where it makes contact with the rockshaft. The rockshaft should contact and stay where the steps are keeping the deck level, but as you can see there is evidence of movement. The deck cam is keyed so there's only one way to install it. I'm thinking that the rockshaft could be bent or twisted. I bought the machine used and the previous owner installed the three point hitch.

 

[Chris_VA]

Hello,

I realize this is an old thread but I haven't found much out there when searching for this. I have a 2015 model 758 and it has been off since I purchased it. At first I'd have to level it every few months, just thought the adjusting bolts were moving in the lock nuts. But this past year, like you guys have said, I adjust it every time I mow and it is off at least 1/2". And within minutes it will be off again while mowing. I'm going to tear into it this winter and maybe see more of what is wrong with it. Just thought I'd post here to see if anyone has successfully found and fixed this issue. If not, I'll certainly post what I find and if I'm successful.

I should have taken it back to the dealer at first, under warranty, but I didn't. I assume these PIP's are covered under the warranty period and not after warranty, correct?

Thanks for any more info if you have it.

Chris

 

[BravoXray]

Is it always low or high, or does it vary up and down from the previous setting?

 

[Chris_VA]

Thanks for the note.

I generally have to raise one side to get it back level. If i have to raise it a good amount, I also generally have to lower the opposite side just a bit. I have not paid close attention to see if I'm running out of upward adjustment on the threads. Also, I'd be guessing if I told you it was the same side that was always lowering. That is part of what I need to dig into this winter. Looking back I should have documented this better, but in the heat-of-the-moment, I just adjust it so I can get on with mowing before dark..

 

[ruffdog]

How level is the deck when you raise it all the way up and you check the clearance of the lift arm to the fixed stops? Initial set-up should have about 1/16" clearance on each side. Tire inflation will really change your mowing height. Do you have a accurate gauge?

 

[osumet]

I just purchased a 2014 X734 with 310 hrs. It's got the 54HC deck. I replaced the spindle bearings and seals and re-leveled the deck. I've been studying my technical manual and the online parts diagrams and have been trying to figure out why the deck is at 2" when it is set to the 2.5" height. Both of the lift arms that are attached to the rock shaft appeared to be at the same orientation. I set the tire pressure per the manual. I started off by adjusting the clearance between the frame and draft arm because I noticed that the draft arm was contacting the frame when in the highest position. I set the clearance to 1/16. I attached the deck, set the height knob to 2.5", and went through the deck level process by measuring to the blade tips. Adjusting the draft arm clearance had taken care of getting the deck pretty level from side to side but I dropped the right side about 1/16" to get it perfect. I then adjusted the level front to back to get the middle blade tip (when rotated to front of deck) 1/8" lower than the side blades. When the deck was off the tractor, I checked the position of the deck height cam stop to the position of the deck height knob. The cam was at it's lowest step when the knob was adjusted to the lowest cut height. I checked it at the 2.5" setting and the cam was at the correct position. Checked again at the highest position and they agreed. I re-checked the draft arm clearance to the frame after leveling the deck and the draft arm is within 1/8" on both sides when the deck is fully raised. Best I can tell, john deere's design prohibits the deck height setting to match the actual blade height. If the draft arm can't be raised any higher without contacting frame, I don't see how the deck could be raised an additional 1/2" to get the actual height to match the deck height knob setting. Looks like I'll just have to remember that the mower is cutting 1/2" lower than it's setting.

 

[ruffdog]

I just drew a red mark with a wax crayon where we mow at. It was easier than "remembering" where to set it.

 

[jonsstihl]

Just remember that there were several configurations in different years. one side has a left hand threaded bolt holding the levers onto the rockshaft so if it won't come loose try the other direction before breaking out the 4 ft cheater pipe.

for the height setting mine is the same (off by about 1/2 inch)