1720 4WD

[TraderMark]

Hi!
I'm a newcomer to the board here so forgive me if I screw up the first few times I post. *LOL*

I recently bought a used 1720 4WD. The sheet metal is a bit rough, but it came with a 7108QT FEL and for the price I couldn't let it slip past me.

ANY way... back to my question.

The 4WD will sometimes disconnect if the front wheels aren't in a hard pulling situation. Anyone have any suggestions on what might cause this?

I want to get the few bugs I've found straightened out as soon as I can.

 

[Bird]

I'm not very familiar with that tractor, but that sounds to me like it would be one of two things: (1) the gears are worn enough they're slipping apart, or (2) the shift linkage is not meshing the gears all the way together. I think I'd want to get that fixed pretty soon, because if I'm right, it's only going to get worse.

Bird

 

[TraderMark]

Hi Bird....
Thanks for the response.
I've been doing some thinking and some more observation on the problem and I think I may have it figured out. Tell Me what you think about this.....

There's a short arm(bellcrank) hooked to the shaft that goes through the trans case to shift the fork..... attatched to this bellcrank is a solid rod linkage that comes up through a hole on the floorboard.... this solid rod is heavy in relation to the rest of the linkages..... I think the problem lies in the mechanical detent mechanism (ball and spring) that holds the shifter fork in either the engaged or disengaged postition. Pulling the rod and lever UP engages the 4WD and the weight of the rod is enough to overcome the weak or broken detent spring and let the shifter disengage.

One reason I think this is My problem is that it seems the rougher the ground I am covering, the more it jumps out of 4WD.... I had to drop into a lower gear with the plow today because the ground was so rough, and with the slower speed and less bouncing around, the 4WD stayed engaged much longer, hardly ever dropped out.

Also.... I can't feel a definitive "click" when shifting in or out of 4WD like when shifting other machines or other gears....

Thanks for listening and I hope this weekend I will know for sure what the problem is. I have the springs and ball ordered from the local dealer here....
Who btw sells <font color=blue>blue</font color=blue> <font color=orange>orange</font color=orange> and <font color=green>green</font color=green> all under one roof!!!

 

[Bird]

Like I said, I don't really know, but what you're saying makes sense to me. You may have it diagnosed and be well on your way to having it fixed. And that sounds like a good dealer, to get all 3 major colors together./w3tcompact/icons/wink.gif

Bird

 

[TraderMark]

Wanted to leave an update on the problem.....
I got the parts from the dealer and there are actually 2 springs and a detent ball that hold the shift mechanism. I removed the shifter assembly and found just one spring in mine, so I replaced what was there and put it all back together. Getting the shifter pin in line with the groove on the sliding gear was a little tricky, but I made it after a few tries.

Any way.... there is definitely a "click" that you can feel when you shift now and so far it hasn't jumped out of 4wd yet.

I ran it about 3 hrs this afternoon piling some brush, but the true test will come in a few days when I put it back in the pasture pulling the disc harrow.

It will be a few days before I can get back in the field after 2 inches of rain Saturday. But that still leaves us 6 inches short of normal for this year already.

Thanks guys!
Mark

 

[djradz]

Glad to hear you fixed your problem. The 1720 is a good tractor. I just recently passed mine on to my dad when I wanted a little more horsepower and bought a 40D. I had mine for 12+ years and it never failed me. Only problem I ever had was the differential lock required more and more pressure to engage it. I think this was a result of too many times being pushed while the wheels were spinning, rather than letting the wheels stop or slow significantly before applying the lock. Also, I found the tractor performed significantly better with weight in the front end. I added 5 suitcase weights, but maybe you'll be ok, having the loader up front instead. Enjoy! ... Duane