New X749 with 54C deck has terrible cut quality

[bubbacuse77]

Don't get me wrong the X749 is worth every penny when it comes to my hilly landscape. No other mower can handle my hills with the stability this thing has but I'm with you all, JD fell short with the decks. I understand that most of what you pay for on these machines is the AWD and the versatility of the machine to be used for other things but still for 13-15k this thing should have the best possible cut in the business considering it is the main task it was made for. I don't have any of the uneven deck issue some of you have however the I have experienced the terrible cut of the JD's mulching kit. I have learned talking with some fellas that mow professionally with Zero Turns and they don't run mulching kits either because of the cut quality.

 

[mikehaugen]

That mower seems too heavy for 7psi.
In some cases I find it necessary to run more air in one front tire to level my old deck up.

How does this work? Don't tell me the x7xx doesn't have a pivoting front axle.

 

[BBO]

How does this work? Don't tell me the x7xx doesn't have a pivoting front axle.

I should have stated that mine is an old 445, but it does have the larger frame and commercial deck.
Book says 8-14psi in front tires. I start at 12psi, then up to 15. I have slopes and the tires seem more stable with more air.

I can't explain exactly how it works but at times I decide one side is lower or higher than the other.
I can add just 1 psi in to one of the tires to level it up.
The tires inflate on top in concave bubble and you can raise the deck even 2" at the ends with air pressure.

My 445 has 16 x 7.5-8" and the rears are 23 x 8.5-12"
And the newer mowers may to have even wider tires than mine.

 

[mikehaugen]

I'm not sure how that works either, but I'll take your word for it.

I wouldn't mind having a 445, they seem like tanks.

 

[Jimh4662]

Well Dealer coming tomorrow to take it in for further research. Said Factory rep coming in to evaluate. This is the second time. Dealer replaced drop links two weeks ago on first return. Glad grass season is just about over. I have a feeling the X758 going to be gone for a while. I will let you all know what and if there is a solution. I just double checked the deck blades depth. After two trips back and forth on my front yard, deck dropped 1/4 inch on right side.

 

[mikehaugen]

Well Dealer coming tomorrow to take it in for further research. Said Factory rep coming in to evaluate. This is the second time. Dealer replaced drop links two weeks ago on first return. Glad grass season is just about over. I have a feeling the X758 going to be gone for a while. I will let you all know what and if there is a solution. I just double checked the deck blades depth. After two trips back and forth on my front yard, deck dropped 1/4 inch on right side.

So are they giving you a loaner in the mean time? How come the rep couldn't come to your house to check it out? Seems like seeing it in action would be the best way to diagnose.

 

[Jimh4662]

Gator: Done that at Least 2 dozen times. I had pressure in front at 22 because I didn't want it spongy. Dealer set it back to 10 lb when he returned the tractor last Friday. I just checked level, the deck was Right on at 3 inches both sides with John Deere Mower depth gauge. Cut two Strips. Brought mower back into level concrete floor of my garage. Checked level again and Right side off by 3/8 inch. My dealer came out to my house. Spent all of two hours double checking my procedure on deck leveling, grass cutting. I. Demonstrated my knowledge of lawn tractor lawn care. Cut up and down and back and forth on my front lawn. Man it looked like it was cut with machete when I was done. . Dealer said, never seen that before. Took it for 8 days and replaced drop link. Coming tomorrow for second repair. Very frustrating. Also I got a bad feeling about the eventual outcome. Deere saying, Don't know. Yours is the only tractor in the world doing this. Must be the deisel fuel your using, it's your grass, should of never put 22 lb in tires now the mechanical plain is off, are you driving with one hand, not wearing your owner edition hat we sent you. Yada, yada, yada.

 

[Gator6x4]

Use the Mower Depth gauge and check the blades to ascertain if one is bent. Check the height on the blade tip then rotate the blade and check the other end to determine if their is any difference.

 

[Jimh4662]

Done it, even measured across all blade tips. Dead on, straight across. Also measured height of spindles thought I had a odd duck spindle. Iam beginning to believe it might be the ridged deck/draft assemble as specified in original post. I went and shook it up and down on the discharge side very little give. I know on my old 4110 if you stood on the deck suspended, it sagged a little. Appreciate all suggestions.

 

[Jimh4662]

Dealer hauled it off about 0730 this morning. Mike, no loaner, didn't offer to bring the rep buy. Why? I could surely speculate being a suspicious person. But so far they been a pretty good outfit. Been proactive pretty much on this issue. I am hoping it's because they stand behind their product. Owned Deere since 1980. From same dealer. First time I have had an issue.

 

[Gator6x4]

If very little upward movement it will not be long before something will give. I don't think the mower lift system was designed to support the weight of the 749 to many times when the anti scalp wheels encounter a high spot and try to force the deck upwards and is tasked with trying to push the deck and the 749 up.

 

[jenkinsph]

I have been watching this thread with curiosity so I just went outside to see how much movement my deck has. I can lift either side a couple of inches, seems to have enough play not to be an issue. I would think if the deck is rigid you do have a problem with linkage hanging up. My x749 cuts evenly with standard blades and the MC519 cart and blower works well. I did not care for the mulching plug when first using it but have to say the grass was taller than it should have been. I may put it back on and see how well it works with normal cutting heights. This summer mowing my lawn I have used a bungee cord to hold the flap open with the standard blades, seems to be alright and spreads the clippings out better.

 

[coobie]

Unfortunately, I would have to agree that the cut quality on the JD X7xx series does suck compared to other mowers I had. The Scag Tiger Cat I had put the JD X748 w/the 60" 7-iron deck to shame. I think it is mainly because the deck on my JD X748 is rigid and does not float like the Scag's Velocity Plus deck, which the Scag used chain links to make the Velocity Plus deck float across bumps and etc. The JD cuts well on the flat areas of the lawn, but when you hit bumps, hills, banks and etc., the mower digs in as shown in the picture I attached. Unfortunately, my X748 has been back to dealer to check this issue and they said it was the tire pressure, but when I got it back, the tractor mowed the same way. Heck my Woods PRD8400 mower on my JD 4520 put the X748's deck's cut quality to shame when cutting the same area, but again the Woods deck floats. I think if JD would make the deck float on the X7xx tractors and put an anti-scalping roller in the middle of the decks, it would improve the cut quality of their deck.

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Have to agree.My 2011 JD X740 with the 7 Iron deck can,t compare (cut quality wise) with my 1996 ingersoll 4020 48 inch deck.My JD deck scalps the heck out of my lawn.Not to impressed at this point.I will address it in the spring of 2014.

 

[Jimh4662]

I checked the movement while set i up position and in the float position. Its tight. Might have an inch or two movement. It would seem likely to have more for better terrain rolling.

 

[JDTank]

I regularly cut with my deck set at 2.75 on the knob, and my yard is quite uneven. Technically, the deck should push up all the way until the arms reach the end of their travel. The deck arms do not have down pressure. The point of the system is specifically so the deck will raise up to allow for uneven ground. If your deck will not lift up when your gauge wheels make contact, something is wrong with your machine.

 

[Gittyup]

Don't know about the newer machines, but on my 425 there are hooks that can be used to lock the deck lift in the up position. However, these hooks can get between the frame and the lift arms, preventing the lift arms from rising to max height. Worth look for anyway.