My Tractor Forum banner

John Deere L120 Turning Radius

6663 Views 43 Replies 11 Participants Last post by  Flaken
Picked up a used L120 and have a problem with the turning on it. Mechanically, it appears fine. You turn the steering wheel, the front wheels turn in the direction you want, BUT you continue moving forward only gradually turning in the direction you want. The turf tyres still have a well defined tread pattern and are inflated to sidewall spec. They just seem to float over the ground. On an asphalt paved surface they do grip a bit better but still appear to float. This is all at slow forward speed roughly one third to one half max forward speed and level ground.
Thinking of getting some ag style ATV tyres for the front or would some type of front weights perform better? Any opinions to solve the problem would be appreciated.
1 - 19 of 44 Posts
Thank you for the reply. Three foot diameter turning circle? Not even close, maybe eight feet at a crawl. The tyres just float. Have a number of trees to mow around of varying sizes and end up having to make 4 passes to cut close. 14 psi in the tyres, you can press on the middle of the tread and depress about a half inch, maybe a bit more.
I somewhat understand the Ackerman steering as I have that on my recumbent pedal tadpole tricycle. That is, two wheels in the front and one in the rear. The other style of trike is a delta style which is opposite with two wheel in the rear and one in front. No, the problem here is that both front wheels are turned at a diagonal, not full turn, yet the lawn tractor still moves forward because the tyres float. Where and how should I attach the 50 pounds of weight?
That is definitely not normal. I had an L120 for eight years and over 400 hours and never experienced anything like that. It is almost like the differential is locked up. What happens if you elevate the rear and turn one wheel by hand?
Dunno, I'll have to give that a whirl and see what it does. But as I said, everything appears mechanically fine. What it more resembles is that the weight distribution is more towards the rear and that is why it floats without turning. I'm 6'4" and 280 but don't think that should affect it that greatly.
Flaken, I think Tundra may have the answer: locked rear end.

Your tractor weighs approx. 530 pounds. That weight s roughly distributed between the front & rear wheels. Now, add your 280 pounds, pretty much over the rear wheels. This is rough numbers, but you've 1/2 your tractor weight, 275#, plus your 280#, or 550# on your rear wheels trying to drive you straight forward...rear end locked and equal power to both wheels. So 550# driving forward with two 9.5" tires tires and 275# (1/2 tractor weight) on two 6.5" tires, guess what's going to're gonna go straight, or straightish!

As Tundra said, jack up the rear of the tractor and turn one wheel. If the opposite wheel turns in the same direction, your rear is locked...and putting all power to BOTH rear wheels. If the opposite wheel turns in the opposite direction, your rear is OK. Jack it up, check, and report back. Bob
Cool!!! That is the best polite way to say I'm fat I've heard in awhile :sidelaugh

All that aside, your explanations make sense.
Was just going to get the lawn tractor out of the shed as I have to move some dirt in a Gorilla trailer. Figger it's easier to pull it with that than me doing it if only for a short distance roughly 30 feet.
OK, just jacked the rear wheels off the ground about two inches. Rotating left rear one by hand clockwise, the right rear wheel turns counterclockwise.
Then I am somewhat in luck. The dirt I'm moving is for a water flow barrier alongside my driveway and have some concrete & rebar. Should be fairly simple to construct a box, embed the rebar to fit over the bumper with concrete and see. 80 pound bag might do it then?
Yes, there is a degree, or two, of toe in. Quite the same idea on my recumbent trike. The wheels are a degree or two off from vertical so that when sitting on the trike, it forces the wheels into the vertical position. Has to do with traction and tyre wear.
OK, measurement at the front of the rim to the front of the other rim is 24¼ inches.
Measurement at the rear of the rim to the rear of the other rim is 24½ inches.
Well that is interesting. My experience is about 8 years and over 400 hours on a L120. I had no issues with the machine as to turning radius. Indeed no issues period with routine maintenance. Traded it for an X540. No comparison on the ease of steering with the hydraulics but basically similar turning radius. Just saying.

Need more info on the front spindles and bushings.
OK, please describe to me what I'll be looking at here with the front spindles & bushings. I haven't been all that deep on this, yet. Waiting on a part for the mower deck that broke while mowing. The idler spring tip where it hooks in the deck rusted through and broke. To me, that's normal for used equipment, something works until it just can't. This steering just isn't normal for me.
Upon further contemplation and rereading what has been posted, I'm a bit unsure of what the spindles and bushings have to do with the tyres floating over the ground and not gripping to turn. The steering appears fine: I turn the steering wheel, the wheels turn in the direction I would like to travel, there is very little to none slop in the steering itself, the wheels continue to rotate. The turf tyres still have well defined tread. It is just that the tyres appear to float and not grip the ground to make almost any type of turn, certainly nothing precise.

I'll be constructing a weight box to fit over the front bumper and fill it with 80 pounds of concrete in a couple of days. I'll see how that works.
Thank you for that bit of info, Tractor-Holic.
No the bushings I have on the front wheels are steel, or at the very least some type of metal as I didn't check with a magnet. With the front jacked up, both front wheels turn freely, that I have checked.
Every L100 series unit I messed with had steel bushings.

I would start out at 40 lbs. The steering gear on these units wear out fast and adding excess wgt will wear it out even faster.
I can understand your perspective, but I am single and on a limited fixed income (SSD). That means I just don't have the spare change to make continuous alterations.

Tractor-Holic: Warm is where it's at! Quite cool today at only 87° and 65% humidity. But outside doing some concrete prep work digging for the forms that I'll mix & pour tomorrow.
Bearings JD part# you will need is AM127304 .also if needing to adjust toe in or toe out, you will want to adjust the draglinks. I would take the wheel off though and check out what the spindles look like first, while you have them off take punch out the bushings and replace with the bearings I listed above, you will need 2 for each side, should have a washer on each side of the bearings too, makes a tighter fit when putting back on the c-clip.

2 bearings, 2 washers and 1 c-clip for each wheel.
Thank you for that, Jimbochap.
As I said earlier today, I somehow just don't think the front wheels are the problem. When raised in the air and rotated, the wheels turn freely with no grinding, flat spots or any type of hesitation. That indicates to me that they are fine. I also don't have the spare change to be throwing it away on replacing perfectly good parts. It's either Amazon or the JD dealer 50 miles away and I can't afford the gas. My truck gets filled once a month.
The front wheels are rotating fine, the steering is working fine. The problem is that the tyres just float over the ground and do not have any grip even though there is well defined tread, they are not slicks. I can agree that my fat *** may be a problem with the weight distribution.
I've already had the dust caps off and the wheels removed. I didn't know at that time that I was looking at the bushings and other. I was looking because I'm still thinking of getting different tyres and was rather curious of how easy they were to remove. My yard and turf tyres do not mix well, been there done that with other machines.

But when looking at everything I've posted, never once did I state anything about the wheels not rotating while turning. The wheels rotate just fine whether straight or at an angle. I watch them rotating as the tyres float over the ground continuing it's forward motion and keep wondering when the tyres are going to bite as I'm also looking ahead to see how close I am to running off the edge of the creek or hitting something.
I think that someone assumed that the wheels were not rotating or had a flat spot or something and everyone ran with that. I kept saying that the tyres don't grip and appear to float. The turf tyres have ample tread remaining.

On a side note, I purchased this L120 from the boss man of the service department of a local dealer of commercial mowing equipment. It was his personal mower he had bought new years ago. Mechanically, it is in good condition or appears to be. The engine area is extremely clean along with the underside.
See less See more
Wanted to give everyone an update on the problem with the turning radius.

I first tried to add weight to the front. Bolted up a platform that stuck out about a foot to the front bumper and added a 50 pound bag of sand. Took it for a test spin about the yard and there was a very minimal improvement. I knew that there was not anything wrong with the wheels or the steering. Then I got some new tyres for the front wheels. Major drastic improvement! My turning radius went from about 8 feet to about 3½ feet. Have some knobbies for the rear coming later this week.

Thank you all for your comments and suggestions.


See less See more
I'm glad that worked for you. If you would do something I'd like to hear the results. Back up around a circle and tell us how well it turns.

I found that my rear directional tires do not grip well in reverse. They'll pull a mountain fwd but won't back uphill worth a darn.
Now something I have noticed with this used lawn tractor is the reverse doesn't work all that well. But it is something I'm not overly concerned with as the only time I really use it is when I get stuck with these crappy turf tyres or putting it into the shed when done. I don't mow in reverse as I try to plan my routes without doing that. Anything else I have a push mower for.

That said, I did motor it out and performed the test you wanted, Steve Urquell. Either forward or reverse, I'm still in the 3-4 foot diameter circle which is much better than the 8 or more foot one that it was. Also drove it around in reverse and the new front tyres steered and gripped nicely.
After reading this thread I can't help but wonder, and I know this sounds stupid but is it possible that the front wheels are steering too far right or left? This would cause pushing. It's hard to understand that new tires with more aggressive tread would help when adding weight to the front doesn't help. That's a strange one. :Orange_tr
Not a stupid suggestion, Howdy Do. The wheels turn about 45° and that's at the hard stops. The problem occurred constantly and not only at those hard stops.
This is just an opinion, mind you, but I think the tyres were simply too old and became brittle and hard. Most of the people here have rather new equipment and while tyres do last a long time, there is a certain life expectancy. I asked my question because I did want to eliminate other possible causes of the new to me used machine that I got.

I have had other used tractors but the steering was never that bad. I do know that the turf tyres and my mowing area just don't mix to my satisfaction.
Just wanted to give an update!
Thank you everyone for your help here. I'll admit that I was rather hard headed and didn't really understand what many of you were speaking of. Today I replaced the wheel spindles with the upgraded ball bearings and the difference in turning is much better. The new ag style tyres work like they should now. Again, thank you all.
1 - 19 of 44 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.