JD 920 hyd system question

   / JD 920 hyd system question
  • Thread Starter
#11  
Can look up parts at the jdparts for the 920.
https://partscatalog.deere.com/jdrc/navigation/equipment/58556

Schematic of the screen location and what the hyd oil filter look like..
Note two different filter covers key #8 and #10 depending apparently on s/n

Thanks, that helps. So basically I'll need to drain the system, clean off the filter, then refill it in order to get the loader off the ground. (I realize there's way more involved in making the system actually right, but in terms of getting the thing back to the farm...)
 
   / JD 920 hyd system question
  • Thread Starter
#12  
The only adjustment for the wet brakes on a JD tractor of that era is adjusting operator pedal height if height is incorrect & bleeding air out of braking system if air is present. No other adjustments were available. Any tech manual designed for a 20 through 40 series JD utility tractor with open center hyd system should be fine. I have a tech manual for a 2040 that covers the open center hyd system. I just sold a Koyker loader that would fit that tractor for $2000,

So how much do the brake pads run, if that's what is causing the trouble?

That does make it sound like I could get a decent amount back out of the loader if need be.
 
   / JD 920 hyd system question #13  
Oh, that's good to know. We bought a bunch of that stuff (cheap motor oil, not diesel) awhile back when it was marked way down. I didn't use it in the cars, so it's just sat.

Also have gallons of surplus 75w90 gear oil that I'd bought for a song way back when, but I'm guessing that's way too heavy for this.

Sure, and now that I think about it, if replacing the JD part didn't fix the problem, then the JD part was probably still good.

Ah ok, that's helpful. Yeah, I was picturing more like a car owner's manual where it has endless diagrams to help people who haven't used a car radio before.

Far as I'm concerned that's part of making it my own...

Thanks again.

Well, the high detergency of cheap lightweight motor oil makes it a good flushing fluid for old open center hydraulics for tractors with manual transmissions. It isn't as good for other systems - especially HST.
You can re-filter flushing oil and re-use it for flushing a few times. Same for diesel. To filter, pour it through some old socks and let the pail of oil sit quietly for a few days. Decant carefully.

I don't know of any use for old 75/90wt. Lube technology has gone to lighter oils with higher shear strengths. That didn't use to be possible; now it's common. Some old rear end drives use the heavy stuff to dampen impact .

It might be that the JD pump works. But it might also just need a rebuild kit. Or need some machining and a rebuild kit. Lots of older JD parts are high quality complicated castings and that makes them worth a small amount if the cast housing is reusable. No biggie either way.

John Deere - and other tractor operator manuals too - tend to cover the mechanical operations we are talking about here. They are heavy on fairly sophisticated step-by-step maintenance procedures.
If anyone ever actually followed all the recommended maintenance laid out in those manuals I wonder if tractors would ever break.

Brakes: I don't know if those are wet brakes - in the parts manual online link that was provided I can't tell. They look like dry brakes in an axle housing extension. Anyone know for sure?
BTW, thanks to "BeenThere" for the link: https://partscatalog.deere.com/jdrc/navigation/equipment/58556

Well, everyone who goes to refurbish an old tractor does so thinking they can sell parts - like a loader - to recover some of their money. Usually it just leads to piles of junk rusting against some fence line. I've been there. BTW, make sure it comes with the 3pt arms and top links. Those too often tend to walk off, and they are expensive.

What you are considering isn't what I'd do, but there was a time with little money and lots of time when I did just that. So all I can say is it is possible plus being a whole lot more work than you can ever know until you do it. LOTS of wrenching....Having any kind of FEL on it makes a big difference. In the end it also depends on whether you believe that engine/tranny starts and runs OK. If everything else was right including the hydraulics you might want to get into a manual transmission - but it's not worth it if you have to do significant motor work.

You learn a lot. Like if it has water in the hydraulic fluid it probably has water in the diesel fuel tank too.
luck,
rScotty
 
   / JD 920 hyd system question #14  
rScotty
Due to the fact that nearly new JD tractors of this era suffered hyd failures I seriously doubt following the maintenance outlined in operators manual would guarantee tractor wouldn't have a hyd problem.

JD 20-55 series tractors had ""wet brakes IE operated in oil"" no matter if hyd system was open or closed center. To replace rear brake disk if required one must remove rear axle housings which requires draining of hyd oil.

JD has decided they were supplying to much info so one can no longer check part prices or parts availability on line. I suppose JD didn't desire customers to determine the % markup over MSRP that some dealers are adding to already high priced parts.:thumbdown:
 

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   / JD 920 hyd system question #15  
I can't tell wet or dry about the brakes. That parts list doesn't show a good exploded view and I'm not up on the German Manneheim-built JDs.
The Manneheim JDs didn't sell well around here - unlike a the bulk of the the 10/20-55 series JDs of that era built by JD in the US & Mexico. Those models are more common. You used to not be able to get out of the truck without tripping over a 3010/3020 or 4010/4020. One in every field.
The 820 and 920 models are different from the other 20 series.

Agreed, having open or closed hydraulics doesn't affect the brakes.
At any rate, I think he would have plenty to do before getting into the brakes. I doubt that alone is the hydraulic problem. It may have contributed.
rScotty
 
   / JD 920 hyd system question #16  
As I previously stated the JD 20-55 series utility tractors built in Dubuque,Ia,Mannheim,Germany or Saltillo,Mexico all have wet hydraulically operated rear brakes. I'm going to guess the bulk of the previous mentioned tractors were built in Dubuque & Mannheim factories with Saltillo coming in a distant 3rd place. Part keys 4 & 5 are designed to hold back oil & key 1 is a brake actuating piston. All models have a similar brake valve with hyd lines leading to each axle housing. There were no smaller lower HP JD 40 series & no 50 & 55 series utility tractors built in Dubuque! Only IIRC the 2 larger models such as 2440 & 2640 were built in Dubuque. Later model 2030 were built in Mannheim not Dubuque.

820,830,920 & early 2040 with 3 cyl engine are all very similar in respect to hyd systems. I was employed by a JD dealer from '66-'87 with 13 of those yrs serving as the service manager & I've never seen a 20-55 series JD utility tractor that was built in Satillo,Mexico & I live within 400 miles of Mexico.

I can guarantee you without a doubt that failed brake linings can be the major cause for hyd system failure on a 20-55 series JD tractor.
 

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   / JD 920 hyd system question #17  
Sounds like you have a world of real experience, Jim. So I've got a couple of questions.
Were the 820/30 & 920 more popular down where you are than they are up here?
And since you were employed by JD during what was some of their best years, what's your favorite model JD from that era?

We sure do like our old JD530. It's a surprising blend of old and new.
rScotty
 
   / JD 920 hyd system question #18  
I was employed by a JD dealer for 21 yrs so yes I've had some JD experience. JD dealership where I was employed sold both 820 & 830's but new 920's were built for sales in other countries than the USA. IIRC there were some new JD utility tractors sold every yr. I think the 50 & 55 series were the most reliable. My favorite is a 4255 that I've owned since Feb.'93. It has nearly 12,000 hrs on the speed/hr meter & has rd baled way over 100,000 bales plus a lot of tillage. My parents farm had a 530 that was traded for a 3010 that was traded for a 4030.
 
 
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