JD 2640 sterring fork replacement

So a friends J-D 2640 broke one of the ears off the steering bell crank. The ear that connects the fork with the long tie rod. He asked it I could replace teh bell crank. I checked out what it would entail and decided it would be easy enough. I secured a new bell crank and went over to do the repair. I removed the 3 ball joints from the broken casting without too much trouble. Removed the snap ring on the bell crank's pivot stud, only to find there is no where near enough room to remove the old part !!! There is a huge U shaped casting that connects the engine block to the front end pivot. The rear of the casting has a pivot stud with a snap ring, a washer and a couple of shims(which I removed), and on the front, a large pivot bolt/nut. Both pivots on that casting are horizontal and the bell crank stud is vertical. The tractor is equipt with a front end loader so I can use it to raise the front wheels off the ground, then block up the frame. It seems to me if I remove the front bolt and nut and remove the entire front axle assembly, thats still not gonna allow me to get that casting off or even allow it to drop down far enough to make the part swap. The rear pivot stud appears to be part of the casting? If it is, how did they ever put the part on to begin with. Can anyone shed some light on this for me? I'd like to finish this project up tomorrow.

After the front pin is removed the front support with axle, has to move forward off the rear pin. You should replace the bellcrank bushings/ bearings when you install the new bell crank.

Well, it wasnt too hard to get the axle seperated and get the bell crank out, BUT, after removing teh old bell crank and ready to install the new one, they sent the wrong one. The one on the tractor has a 1 1/4 shaft, the one they sent has a 1 1/2 shaft . Bummer. So I get back to the house and call, the company that sold me the new bell crank doesnt have a clue. They dont have the correct one. Ive searched for hours and no website that sells John Deere parts has a clue. No one has any measurements or the correct part # to order. Back to the shop and blast off the old paint and muck to look for casting numbers. I found THEM. This bell crank has 4 different numbers on it.

And the parts catalog shows two different front axles with multiple bell crank options and several different part numbers for the casting numbers. The same casting can be used for multiple parts as the part number is generally assigned to the finished part, not the casting. Look carefully for a check mark, or such, next to one of the casting numbers. Sometimes that might give a clue.

Maybe some choices can be eliminated. Which front axle does it have, Straight or swept back? Look for a casting number on the axle. Does the support have bearings or bushings for the shaft? I am guessing bushings as the T23118 bushing shown (item key #4 is 1-1/4" ID. What was the JD part number of the bellcrank you ordered?

Here is a link to the parts catalog for the 2640 in the serial number range for the one you posted. The bell cranks are in section 80 WHEELS, FRONT AXLES, SHEET METAL, with the front axles.

https://partscatalog.deere.com/jdrc/navigation/equipment/79943

It has the adjustable straight axle. The support that the pin on the bell crank goes into, has a bushing. I blasted around all the numbers. No check mark or other marks. The one I ordered was part number R70764. The one that came off the tractor had R70765

(quoted from post at 21:23:02 11/06/23)
It has the adjustable straight axle. The support that the pin on the bell crank goes into, has a bushing. I blasted around all the numbers. No check mark or other marks. The one I ordered was part number R70764. The one that came off the tractor had R70765

Click to expand...

Using the parts catalog, casting number R70764 appears to be John Deere part number AR92945 bell crank for the straight axle. The same casting number on the setback axle has part number AR92944. I don't find the casting number R70765 shown for any of the 2640 bell crank options, it likely matches to a different machine's bell crank.

Given the T21502 casting number and the first choice for a bell crank that has that casting number on straight axle parts page is part number AT19793, I would see if the vendor has one of that part number and see if they will measure it for you. That is the same casting number and part number used with the T23118 bushings on a 2030. I expect the ones with the 1-1/2" shafts were used with needle bearings, not bushings.

Best to order by a part number, the casting number can help ID the right part number, however such as in this case, one base casting can have several casting numbers that may be referencing different machining steps to be done to make several different part numbers from that one casting. Depending on the original casting, shaft diameter and shaft length changes could easily make several different parts from the one casting.

Mutt,

You disappeared, Any Progress?

somewhat. I managed to find a company that had the right one. They said they had a warehouse in Dallas, so I paid them and went and picked it up. I didnt really plan
to leave the tractor sitting with a jack under it, so I raised it up on the bucket and blocked it up. I spent an hour trying to stab the casting for the time being.
The bucket leaks down pretty quick so it's trouble having to work by yourself. I did figure out a solution, will go and give it a try Monday. I can see the
original bolt barely in the front mount when trying to line things up, but I cant roll the jack, cause it's sitting on the dirt which is soft right now. I find it
pretty impossible to hold up a 300 lb. casting on a jack and still be able to line both pins up. So I got a bolt about 2 longer than the factory bolt, then
machined a spacer with a 3/4 hole thru & 1 1/8 o.d. x 1 long that tapers down to 13/16 I can get the bolt to go into the front of the casting no problem, then
insert the tapered spacer on the threaded end and pull it up close with the nut and use the jack only to line up the rear pin.

Good you got parts.