kennyd
Advertiser
They are not proprietary, they are made by Pioneer. My tractor uses the 1/4 size and I can buy them at TSC.
JD 790 300 loader
- Thread starter adamls78
- Start date
- Views: 43298
They are not proprietary, they are made by Pioneer. My tractor uses the 1/4 size and I can buy them at TSC.
kebo
Elite Member
- Joined
- May 16, 2006
- Messages
- 2,928
- Location
- Lexington, SC
- Tractor
- 2001 John Deere 790 4x4, bar tires
Today was the day! Finally had everything together and even the weather cooperated, about 83 and sunny here. NICE!! Took one of the loader hoses loose and connected the gauge. Cranked it up and ran it up to about 2400rpm's and got a reading at just about where it should be, slightly over 2000psi. So, shut it down and bled off the pressure again. Took the cap off of the relief valve and pulled it off. The little cylinder thingy in it with the factory shims stayed in. So, tapped the cylinder thingy out and added a full pack of (4) shims which had two thick ones and two thin ones in it. Because I had read that some folks were adding an extra shim, I pulled a thin one out of the 2nd pack I bought and put it in as well. Got it all back together with a new o ring and fired it up. Took a reading and it was dead nutz on 2500psi. I didn't get to do any real loader work with it after that, but I'm gonna run it like that for a while and see how it goes. If it seems to be overdoing it, I'll take the last little shim out and see what it drops it down to. Thanks for all the help!
kennyd
Advertiser
2500 PSI seems to be the magic number for the 790's.
dirt ditch
Platinum Member
seems to be a good compromise between performance & safety.
Got rid of the last of the old bales yesterday.
The 790/300 did a great job loading and unloading bales even though a couple of them were still quite heavy.
Last edited:
Barely Smokin'
Silver Member
Man, this is great info on the pressure relief shims. Couple thoughts:
- I've noticed big improvements in hydraulic power after an oil/filter change. Maybe file that in the obvious but easily overlooked file.
- Also, and I apologize if I've missed this, but does anyone have a feeling for what the load capacity (regardless of PSI setting) is on the mechanical loader assembly itself? Whatever 2500 PSI will lift? I usually have an attachment on the back and, with the low factory PSI setting, I've never lifted the rear tires off the ground although I overload it all the time with pallets of brick, piles of logs, trees, etc. Occasionally, though, I'll go at a stump from an angle and maybe tweak one rear tire off the ground...and I always wonder what the "breaking point" is.
- I've noticed big improvements in hydraulic power after an oil/filter change. Maybe file that in the obvious but easily overlooked file.
- Also, and I apologize if I've missed this, but does anyone have a feeling for what the load capacity (regardless of PSI setting) is on the mechanical loader assembly itself? Whatever 2500 PSI will lift? I usually have an attachment on the back and, with the low factory PSI setting, I've never lifted the rear tires off the ground although I overload it all the time with pallets of brick, piles of logs, trees, etc. Occasionally, though, I'll go at a stump from an angle and maybe tweak one rear tire off the ground...and I always wonder what the "breaking point" is.
DWCox
Silver Member
I added the shims (790 with 300 loader) and checked the pressure. It is ca. 2550-2600 psi, which is squarely within JD's spec. listing of 2422-2698 psi for the 3005.
The performance of both the loader and 3-point hitch was immediate and marked. I am removing full buckets of moist clay from a pond excavation, and prior to shimming I could not lift a full load in the bucket without the by-pass kicking in. It was very frustrating. Likewise, if the box blade was filled with wet clay and I had to lift it up and down to shake it out, I often found the 3-point hitch having some difficulties. Those troubles are completely gone on both counts. The loader can now break out and lift a full bucket of moist clay with no by-pass kicking in. So also the 3-point hitch. It is obvious why JD bumped up this pressure for the 3005. It is very helpful.
The performance of both the loader and 3-point hitch was immediate and marked. I am removing full buckets of moist clay from a pond excavation, and prior to shimming I could not lift a full load in the bucket without the by-pass kicking in. It was very frustrating. Likewise, if the box blade was filled with wet clay and I had to lift it up and down to shake it out, I often found the 3-point hitch having some difficulties. Those troubles are completely gone on both counts. The loader can now break out and lift a full bucket of moist clay with no by-pass kicking in. So also the 3-point hitch. It is obvious why JD bumped up this pressure for the 3005. It is very helpful.
Did you add one shim kit?
DWCox
Silver Member
Yes, just the one kit.
I probably should break down and put a guage on mine. I added one kit and it helped but not dramatically. Of course I don't do much loader work and as long as the 3pt lifts my box blade I'm OK. However, I just added my toothbar and 4 suitecase weights to my BB and plan to get 2 more suitecase weights so if I run out of lift I will need to put in some more shims.
