2520 popping out of 4WD

[pdp11]

I had posted this picture earlier in the thread. There is nothing in the service manual called a "button".

The thing that makes the most sense are the detent balls (DQ in the photo). It seems odd that they would be bad or defective, although I could see how one might go missing during assembly. I also have a hard time seeing how you can slide the collar far enough on the shaft to get to them with only the side cover removed.

Maybe he was talking about the bearing block that is on the end of the selector shaft that actually moves the collar. That would be something you could get to through the side cover, and might be considered "button like".

 

[Gobblin Tom]

I'm now wondering what my mechanic was talking about. I agree that there is no part called a "button" on the diagram. I'm starting to think that it was the balls. I asked him twice and he said button but I will find out and settle this.

:thumbsup:

 

[sunnyside360]

There is nothing in the service manual called a "button".
The thing that makes the most sense are the detent balls (DQ in the photo). It seems odd that they would be bad or defective, although I could see how one might go missing during assembly.

I personally believe the terms button and detent ball are one and the same. Quite possibly a ball may be missing, wrong size ball installed, defective ball and/or spring, or detent is not properly made. IMHO, there is only one way to know what it is for certain and that requires a competent JD tech like ZR7400 had.

 

[PCABE5]

I think we are missing something. A missing ball will not allow the lever to go to the floor. The decent balls hold the collar in/out of 4wd. If the lever moved that freely it wasn't engaging the collar. Detention balls or not the lever can only move so far when it is engaged with the collar. Without detention balls he still would have had 4wd he just would have had to hold the lever.

 

[megaboz]

I think we are missing something. A missing ball will not allow the lever to go to the floor. The decent balls hold the collar in/out of 4wd. If the lever moved that freely it wasn't engaging the collar. Detention balls or not the lever can only move so far when it is engaged with the collar. Without detention balls he still would have had 4wd he just would have had to hold the lever.

Since the mechanic didn't even notice it when it went all the way to the floor the first time, I sure as wouldn't trust much of what he said in the first place.

 

[glc24]

I'm still thinking it has everything to do with the detent ball setup,and a lever going all the way to the floor doesn't seem right either.

Greg

 

[Henri88]

Update: I got my tractor back from the dealer today. I sure wish I could try adding the extra ballast weight to see if it has any effect, but I got it back in worse condition than when it went. I wasn't home when it was delivered, but I checked it out as soon as I got home. The 4wd lever now goes clear to the floor board and there is no longer any detent clicks, just a smooth glide from the the 2wd position to the floor. To make things worse, when the lever is down it is not engaged in 4wd even though the light it on. It's now screwed up more than it was. At least before I had 4wd even though it would pop out occassionally.

Tom, Smart move not letting them take your tractor!!!! Now the dealer is coming back out monday morning to pick my tractor up again for who knows how long. Needless to say I'm not happy!!!!!!

On the ballast issue: It may or may not work to prevent it from popping out of 4wd (yet to be determined) but I think the recomendation by Deere is a half *** solution to a design flaw. I've searched the internet extensively regarding this and no one is complaining much about their tractor of any brand popping out of 4wd unless they own a JD 2520. No one can tell me that it's unreasonable to expect your tractor to stay in 4wd with a modest load in the bucket with or without a ballast box. I agree that it is safer for stability purposes, but that isn't the question here.

For some of you, read his update. His original problem was the 4WD popping out, when he got it back from the dealer, it wouldn't not engage anymore, so I assume that the detent ball may have been the factor for the 4WD to disengage and the mechanic made a mistake wild reassembling it causing the problem of not engaging when he receive it from the shop. He also mention later on that when he return it the second time the mechanic repair his mistake plus he also replace the button which we assume is the detent ball, hoping this would take care of the 4WD popping out.

 

[PCABE5]

For some of you, read his update. His original problem was the 4WD popping out, when he got it back from the dealer, it wouldn't not engage anymore, so I assume that the detent ball may have been the factor for the 4WD to disengage and the mechanic made a mistake wild reassembling it causing the problem of not engaging when he receive it from the shop. He also mention later on that when he return it the second time the mechanic repair his mistake plus he also replace the button which we assume is the detent ball, hoping this would take care of the 4WD popping out.

Now that sounds right.

 

[Henri88]

I stopped by the dealer today and they have my tractor apart waiting on parts. The mechanic wasn't there, but I spoke with the store manager. Appently they found something broken that wasn't noticed the first time they had it apart. They have been in contact with JD and think that this part was the cause of the 4wd popping out in addition to the 4wd not working at all when they brought it back last time. I don't know but I hope it comes back working properly this time with the 4wd fixed once and for all. I will speak with the mechanic and find out what part they are talking about and let you know in case this fixes the problem. I have not called JD yet, I'm kind of waiting to see if it comes back fixed this time. They are trying to get it back to me by Saturday.

I got my tractor back and so far so good. It hasn't popped out of 4wd since I got it back this most recent time. I talked to the mechanic and he said that he replaced a part called a "button". Aparently that part pushes against the detent. He said that he saw some issues with it that he didn't see the first time he took it apart. The good news is that he didn't have to split the tractor to replace, he was able to replace it by just taking off the side cover of the transmission where the 4wd shifter goes in. Maybe the new "button" and/or the tire pressure changes have solved the problem. I'm keeping my fingers crossed.

Here are a couple of his quote. The question remains, is ''the button'' really the detent ball and if so can you get to it by the side cover, and as far as the 4WD not engaging, I'm sure that was the mechanic mistake.

 

[Gobblin Tom]

That's why I wander if it is even fixed at all? Something doesn't make sense....