JD 4720 doesn't go as fast as it should

[FatSlob]

ok. well I didnt get the option with my machine but I suspect you do. im reading my manual and it says it is activated through your cruise control switch which explains why your speed only goes to 7 and your cruise light is on. Turn off the cruise control. the switch should have a picture on it like the indicator on your dash. I would check mine but it is at the dealer for warranty work. I can take a picture of what the manual says about how to activate speed match but give me a minute. Once you turn off your cruise, the indicator should go off on the dash and your machine should be good to go for 18mph

 

[FatSlob]

Click the image to enlarge it. I spilled some of my burboun on it. tells you how to turn off at the end. guess I was wrong about turning the switch off on cruise. looks like there is another simple step to turn off but involves cruise switch

 

[jenkinsph]

Click the image to enlarge it. I spilled some of my burboun on it. tells you how to turn off at the end. guess I was wrong about turning the switch off on cruise. looks like there is another simple step to turn off but involves cruise switch
View attachment 333181

I haven't used the speedmatch function on my 4520 but would have assumed that if you turned the key off it would need to be reset to use again. Interesting to see how this works out.

 

[Furu]

Sure sounds like the speed match. My manual like above tells how to turn it off and states nothing about turning the key off resetting it. It will be interesting to see how OP responds after going through the procedure. I have a 2007 4720 as well but do not have the speed match option. to try it on.

 

[tlb224]

I tried to get it working this morning. Don't think I have speed match. I was able to lower the mph by .5 at a time by toggling the cruise switch but couldn't get it to go up. Also, the instructions refer to an acceleration and deceleration switch, not sure what that is.

I called JD to see if one of the techs knew, they are to call me back.

 

[Danscaper]

Is the motor dying down while trying to accelerate to 18mph? If it is not dying down, you are either in range B or have speed match on. Range b has a top speed of 7mph. If your rpms are up at 2500, and you have the pedal to the floor maxed out in c range, its the speed match. Even with dirty filters, you would hear the motor fighting while turning the pump to achieve top speed

 

[tlb224]

Danscaper, thanks for that. The tractor accelerates just like a 4120 we have but stops at 8mph. It is definitely in C.
I took it to John deere last night and they will hang the computer on it.

I think it is something simple like speed match but have no idea how to turn it off or reset it. I don't have a switch like the manual says.

I'll post when I hear back from them.

 

[greasemonkeyok]

Don't know about yours, but with mine you can't get top speed without running the engine at PTO rpm. Apparently the pumps can't move enough fluid at slower rpms to reach top speed. Try it.

 

[tlb224]

Thanks, yes, I had the throtte full, it maxed at a little over 2500 rpm, just above PTO. I got up to 8.0 mph this time, .4 more than last trip... still not good.

 

[tlb224]

The problem I'm still having is following the instructions for the speedmatch. My guess is I do NOT have it installed since there is not a seperate toggle for this in my cab.

The instructions refer to the "accel/decel switch", what is that?

Using SpeedMatch Option (eHydro)

SpeedMatch enables the operator to set the desired maximum travel speed for the machine. Full forward or reverse pedal travel distance can be used to control machine travel speed between stop and the desired maximum travel speed.

1. Depress forward travel pedal until desired maximum travel speed is reached.

2. Fully depress bottom of cruise switch to activate speedmatch function.

3. Fully depress bottom of accel/decel switch to set maximum travel speed.

4. Release forward travel pedal. Completely depress forward travel pedal to achieve desired maximum speed.

5. Adjust maximum travel speed:

· Fully depress top of accel/decel switch repeatedly to increase speed by increments.

· Fully depress bottom of accel/decel switch repeatedly to decrease speed by increments.

6. Fully depress top of cruise switch to return switch to middle position and disengage speedmatch.

 

[greasemonkeyok]

Speed match is like your curise control on a vehicle, and the "accel/decel switch" on the tractor serves the same function as in your vehicle, a way to adjust the ground speed up or down.

 

[tlb224]

Thanks, I understand the feature, I just don't know which switch is the accel/decel switch... what image is on it?

 

[greasemonkeyok]

Thanks, I understand the feature, I just don't know which switch is the accel/decel switch... what image is on it?

I.m not at the farm, but I will look in the book when I can.

It was confusing to me at first, and I learned just by using the switches.

 

[Danscaper]

Just thumbed through my manual. There should indeed be a an accel/decal toggle switch next to the cruise control switch on the panel if your machine has speed match option. It would be a switch to the right of the cruise switch. It is possible that the previous owner had hired help or younger adults or kids that used the machine and he did not want them using his machine above the speed your getting. So its possible that he set it and removed the switch and put a plate over the empty spot. Im just tryin to think outside the box because from your explanation, this machine is deffinately getting a signal to the E-hydro not to go over the speed your getting so it is electronically retarding flow to pump to maintain speed

 

[arlen4720]

I'll play around with mine today, I thought there was a way to use SpeedMatch without the upgraded cruise option, but I didn't see it in the manual.

 

[tlb224]

Awesome, thanks again for all this help. I wish I knew more about the tractor...

 

[tlb224]

I'll play around with mine today, I thought there was a way to use SpeedMatch without the upgraded cruise option, but I didn't see it in the manual.

Any chance you were able to crack the code on your 4720?

 

[arlen4720]

Any chance you were able to crack the code on your 4720?

Sorry, I forgot about it. I almost feel guilty enough to go back out in the barn, but I just showered. I will be running it first thing in the AM.

 

[murphy1244]

Sorry, I forgot about it. I almost feel guilty enough to go back out in the barn, but I just showered. I will be running it first thing in the AM.

You should.

 

[FatSlob]

You should.

x2. a real sport would grab a glass of jack daniels and go out and make sense of it.