JD 790 300 loader
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kebo
Elite Member
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- May 16, 2006
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- Lexington, SC
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- 2001 John Deere 790 4x4, bar tires
Read back up a few posts. Most are setting them to 2500PSI or slightly less. I plan to set mine to about 2450 when I get the chance to do it. I have everything needed to upgrade mine, except time.
dirt ditch
Veteran Member
Right now my 790 is set at 2400psi @ 2000rpm which works well for me.
I don't know what the upper pressure limits are on the 790 / 300 hydraulic system. A couple bad things I can think of from too much pressure are, blowing seals, buckling the cylinder tubes when the loader is raised with a heavy load, or tipping the tractor over.
If it was me I'd back the pressure off then see how that works for awhile. If you still need more lifting ability then may have to think about a larger tractor.
just my $.02
I don't know what the upper pressure limits are on the 790 / 300 hydraulic system. A couple bad things I can think of from too much pressure are, blowing seals, buckling the cylinder tubes when the loader is raised with a heavy load, or tipping the tractor over.
If it was me I'd back the pressure off then see how that works for awhile. If you still need more lifting ability then may have to think about a larger tractor.
just my $.02
kebo
Elite Member
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- May 16, 2006
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- Lexington, SC
- Tractor
- 2001 John Deere 790 4x4, bar tires
Well, I was all set to jack up the pressure on my 790 yesterday and I had the gauge, the o-rings, and two shim kits. I disconnected one of the hoses to the FEL and went to pop in the gauge only it didn't fit. I bought the pressure gauge and the quick connect fitting for it at a hydraulic shop that's right on my way to work. They guy gave me the one he thought would fit my quick connect hoses, but it's just a bit too large. See the picture below. It looks like the fitting on my tractor is about 2/3rd's the diameter of the one he sold me. So, I'll be stopping by there on Monday to get the right fitting, or a refund. When I bought this fitting, I didn't have a picture or a part number to show him so it's a little dumbness on my part. But, I have a picture of the correct fitting that was posted here on this thread, and a measurement to take back, so hopefully he can match it up and swap it for the right one. Maybe next weekend I'll get this done!
dirt ditch
Veteran Member
Perhaps this will help?
The quick couplers I bought at the JD parts counter for my gauge are marked as follows.
MALE: Pioneer 4010-2P
FEMALE: Pioneer 4050-2P
The quick couplers I bought at the JD parts counter for my gauge are marked as follows.
MALE: Pioneer 4010-2P
FEMALE: Pioneer 4050-2P
Willl
Elite Member
JD's QC are standard size ?, don't quote me but I thought they where JD only size. Proprietary like.
dirt ditch
Veteran Member
Can't find the sales receipt for them, but my better half was the one who went to JD and bought them. She told the parts clerk she needed quick couplers for a 2007 790, He had to look them up before he could get them for her. The Pioneer quick couplers worked.
Willl
Elite Member
This is interesting.
JD's part # for 'their' QC male fitting is AM37983
A Google search on AM37983 pulls up this PDF of Goodyear fittings.
A search in that PDF for "AM37983" pulls up what I believe is Goodyears match for that JD fitting, (GY's # QS41-02P)
Now this is the interesting part.
If you do a search for "QS41-02P" in this same PDF from GY, you get many matches of this fitting under the different brand names/numbers.
Including your Pioneer # Dirt.
Give it a try.
Kebo, maybe take this PDF and highlite all the matches, print and take it with you.
"Proprietary like", maybe not.
JD's part # for 'their' QC male fitting is AM37983
A Google search on AM37983 pulls up this PDF of Goodyear fittings.
A search in that PDF for "AM37983" pulls up what I believe is Goodyears match for that JD fitting, (GY's # QS41-02P)
Now this is the interesting part.
If you do a search for "QS41-02P" in this same PDF from GY, you get many matches of this fitting under the different brand names/numbers.
Including your Pioneer # Dirt.
Give it a try.
Kebo, maybe take this PDF and highlite all the matches, print and take it with you.
"Proprietary like", maybe not.
foggy1111
Elite Member
There was some confusion when I got my coupler from the JD dealer too. Mine are Pioneer couplers too, but these are smaller couplers than commonly found on other tractors.....and if I remember right they had both the O-Ring coupler (straight pipe threads) and one with tapered pipe threads available.
I got one with the straight threads (for O-Ring seal) and picked up an O-Ring type fitting at the automotive store to use with it, and reduced from there to fit the gauge (my auto store makes hydraulic hoses too...hence a large selection of fittings).
I got one with the straight threads (for O-Ring seal) and picked up an O-Ring type fitting at the automotive store to use with it, and reduced from there to fit the gauge (my auto store makes hydraulic hoses too...hence a large selection of fittings).
kebo
Elite Member
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- Lexington, SC
- Tractor
- 2001 John Deere 790 4x4, bar tires
Thanks guys for the replies. I will print out the pdf file and take it with me when I stop by the hydraulic shop. Now that I have something to show him, hopefully the guy will have what I need. If not, I guess I'll be making another trip to my JD dealer.
