JD 730 trans

[Karl Kostman]

Hello folks I hope everybody had a very good weekend!
This weekend was our Plowing weekend using nothing but old tractors, lots of John Deers a few Farmalls a cool and a few MMs, its a weekend I look greatly forward to every year!
My tractor is a 1959 730 Diesel Row crop wide front and this is what happened. I got to the fields we were plowing early am and got hooked up to a 4 bottom JD plow just like always. I got lined up in 3rd gear as always and took off the first thing I noticed is this was the hardest plowing soil I have ever seen, after struggling for while I finally shifted down to 2nd gear and although it was still pull harder than anything I have ever pulled it was making it just slow. I was on like my 5th pass and the field was a mile long so a round is two miles and I was going to put fuel on after this pass when the tractor made a very BAD noise and gave a real jerk, it did it 5 more times by the time I was to the end of the field. The next pass to to see if it effected more gears than 2nd I tried 1st gear, made it a couple hundred feet and 1st gear same thing but 3rd gear was fine. OK it doesnt take a rocket scientist to figure out I have a gear or gears inside my transmission that are going to pieces. In looking at the manual this looks to be a pretty big deal to rebuild the transmission. Do you folks have any suggestions on how or what I could do to make sure that this is what is needed? I think I know the answer already but grasping for straws here! Any suggestions pertaining to this would be greatly appreciated!
Thanks much
Karl

 

[MikeJM]

The John Deere two cylinder transmission in the 730 is basically a 3 speed with reverse trans with a high/low on the input.

So through some shifters inside when you shift around the bottom you are shifting the high/low set.
So depending on what trans you have, most share 1-3, 2-5 and 4-6. The only difference is whether it goes through the gear reduction or direct.

I suspect you ve lost some teeth on the low range.

They re not hard to work on, but getting certain gears and things off can be difficult if you don t have or don t know someone with pullers to pull them off without damaging.
Definitely have to pull the shifter out to see what s wrong in there, also need to pull the first reduction cover too if you decide to tackle it.

 

[Scott 730]

Can you describe the "bad noise" a little better? I went through my 730 a few years ago. Mine would bang and lurch but always keep moving. Bearing on the right end of the upper shaft went south and trashed the end of the shaft in the process. Be aware, the bearing on the left end of the top shaft has been NLA for years.

 

[Karl Kostman]

Scott it was pretty loud and sounded like it was coming from the right side of the platform where your right foot would be, it sounded pretty metallic and the tractor gave a pretty hard jerk when it happened.
I hope this help in your thoughts on this Scott? Another question, if this is the problem and the bearing is truly NLA what are my other courses of action?

 

[Scott 730]

(quoted from post at 20:29:21 09/12/22) Scott it was pretty loud and sounded like it was coming from the right side of the platform where your right foot would be, it sounded pretty metallic and the tractor gave a pretty hard jerk when it happened.
I hope this help in your thoughts on this Scott? Another question, if this is the problem and the bearing is truly NLA what are my other courses of action?

Need more info. Tractor keeps moving? Trans stick stays in gear?
My issue was not with the LH bearing, my issue was with the RH end of the top shaft. I just brought up the LH bearing availability as an FYI. The RH end pilots into the stub shaft that goes to the first reduction. The RH bearing went out and trashed the RH end of the upper shaft. Also the bearing on the stub shaft was out, which wore the race area of the stub shaft. Because of all the tolerances being out of whack with wore out bearings, the gear that slides on the RH end of the upper shaft, which locks the upper shaft and the stub shaft together for direct drive ( the left hand speeds on the quadrant}would pop out just enough to make a pop and lurch. My stick stayed in gear and never lost forward motion.

My issue kept me from using 4th gear for heavy tillage work for years until I got tired of poking along in 3rd and went ahead and fixed it.

This post was edited by Scott 730 on 09/12/2022 at 07:23 pm.

 

[Karl Kostman]

Good day Scott
I didnt think about it really till you asked but the day after my problem started and I knew 3rd gear was working fine I was going out to plow the headlands that morning and was in 4th gear just pulling the
plow it was not in the ground and the tractor popped OUT of 4th gear, and that had never happened before in the 5 years I have owned it. The shift lever was not out of its slot but was near the end, I pulled
the clutch and put it back into 4th and preceded on. Not at anytime in any of these problems did the tractor stop pulling or moving!
Scott thank you for taking the time to help me with this issue, it much appreciated!
Karl