B7500 Loader pressure increase questions

jayfrank5074

New member

Equipment
B7500
Dec 30, 2014
20
0
0
Bailey, MS
Hello all! First post. I usually lurk and search, but can't find my answer.

I have a 2003 B7500 with the LA272 loader on it. It's weak IMO. I have checked pressure and want to bump it a little up to around 2200psi. I do believe that's what the LA302 loader pressure was. Or does anybody think it's ok to go a little higher? If the la302 was 2200, could I go 2300 or 2400?

Best I can tell the only difference between the la302 and la272 was 200 psi and a grill guard.

Where is the correct relief valve to do this? I have shims in hand, I have a pressure tester etc.... is it on the loader valve? Or down on the right side of the transmission housing by the filter?

I know this tractor is small, but it won't lift the front end without curling the bucket, and sometimes then it won't still. Most times a full bucket of dirt will not pick up, I have to back up some and let some fall out, or tilt the bucket to get some out to lift the loader arms up.

It has 165 hrs on it, I serviced the fluid at 153 hrs when I got the tractor.

Any help is appreciated.
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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Sandpoint, ID
If you have 2200PSI and it's won't lift the front of the tractor sounds like you have bad lift and / or curl cylinder seals.

How many lines come off of the loader valve?
 

jayfrank5074

New member

Equipment
B7500
Dec 30, 2014
20
0
0
Bailey, MS
If you have 2200PSI and it's won't lift the front of the tractor sounds like you have bad lift and / or curl cylinder seals.

How many lines come off of the loader valve?
4 lines I think, total I'm not sure, but I don't have 2200, i checked it cold and got around 1900, i will recheck with warmer fluid this weekend or tomorrow if I get a chance.

I don't have any leaks, you can hear it bypass when you try to do the stuff I am talking about.
 
Last edited:

Bulldog

Well-known member

Equipment
M 9000 DTC, L 3000 DT
Mar 30, 2010
5,440
73
48
Rocky Face, Georgia
My brother had a 7500 with 302 loader and it was very strong for it's size. If anything it was to strong. We had to really pay attention to how much was in the bucket because it would pick the rear tires of the ground even with a box scrape on there. I would expect the smaller loader to be a little weaker but yours sounds to far off.
 

jayfrank5074

New member

Equipment
B7500
Dec 30, 2014
20
0
0
Bailey, MS
I agree, it almost never pulls a rear tire unless on a hill with the rear uphill, and even then not to often.

Rear tires are not loaded.

3pth seems fine lift wise, 5 ft disc is effortless to lift. I know it's not to heavy but...


I don't have a problem shiming it to at least 2200, but I don't know where the relied valve is whether it's on the loader valve or on the transmission by the right side filter. I had hoped someone had done it to tell me.
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,306
4,856
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Sandpoint, ID
You have 1 line in (pressure) and 2 out (power beyond and return) and 4 control lines (to loader).

With type of valve you might need to adjust the loader pressure relief or bypass valve and not the system pressure or bypass valve.
 

Hammer Head

New member

Equipment
L3800 LA524 B77, Ford 1720, Scag Tiger Cat
Oct 6, 2013
13
0
0
Lock Haven, PA
I am not sure where the relief valve would be on the B7500?
I shimmed my relief valve "L3800". The valve was on the bottom of the hydraulic block mounted under the right foot well. All of the supply hoses are distributed from the block to the hoe and FEL.
I bumped mine up to 2700PSI and what a difference, it gave me an additional #300 lift.
 

jayfrank5074

New member

Equipment
B7500
Dec 30, 2014
20
0
0
Bailey, MS
I did not get a chance to do anything to it today, but did notice the bucket has been up since Saturday about 2 ft off the ground. That makes me think the cylinders are not leaking or bypassing internally. The bucket has never leaked down when I left it up.

I guess when I get a chance I will Maybe tear into the valve and see if I can figure it out.
 

jayfrank5074

New member

Equipment
B7500
Dec 30, 2014
20
0
0
Bailey, MS
This was so easy it wasn't funny. On the lowest part of the valve there is a 22 mm plug. Take it out, the spring and a silver piece come out. Stack shims under spring. I stopped at 2300psi semi cold. It's probably 65f and I only let it run just a minute. I added 350-400psi.

It is raining here or I'd try it out, but in my shop it will lift the front tires at idle.

I'm very pleased with this mod so far.

I hope this helps someone else with a b-series.

Shims part numbers are

.4mm 31351-37950
.2 mm 31351-37960
.1 mm 31351-37970

My local dealer ordered them for me at $ .27 each.

Gauge cost me $13 off amazon and the quick coupler was $8 from a local fitting house. Sorry I did not keep the fitting part number.
 

Billdog350

Member

Equipment
Kubota L3710 HST,L2230A QT,forks,Takeuchi TB125, 60" Luck Now pto Snowblower
Jan 6, 2014
468
5
18
East Hampton, CT
I shimmed my B9200 BF350 several months ago and LOVE the results. Only downside has been that I cracked both of my front rims with the heavy loads. Even with a counterweight, the machine can lift the rear off the ground. Not for the faint of heart! If you're comfortable with your machine and have been operating it for years and need a little more oomph, then its a great mod. However if you don't like the machine teetering on two wheels, don't shim too much ;)
 

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RIDETOEAT

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L4600, LA764, LP Blade,
Dec 26, 2014
132
0
0
Southern Indiana
How many pounds are you guys able to lift on pallet forks. I was hoping my new L4600/LA564 loader would exceed specs a few hundred pounds as maybe a little built in safety factor. But in the case of tractors and loaders, specs seem to be specs !! Mine is on the money and not completely up to the task I wanted which was lifting pallets of wood heating pellets. Either way it was still the biggest tractor I was willing to buy for my other uses so all is good in having to break pallets down a little before moving around.
 

Billdog350

Member

Equipment
Kubota L3710 HST,L2230A QT,forks,Takeuchi TB125, 60" Luck Now pto Snowblower
Jan 6, 2014
468
5
18
East Hampton, CT
Ridetoeat, you will be surprised how large of a machine you have to buy in order to lift the 2000# pallets of pellets! With my bucket and forks (which move the load further forward than I'd like) I can lift an ADDITIONAL 800-900# with the proper counterweight.

Your machine should be able to lift 1200-1500lbs depending on your fork and bucket setup and how high you need to lift. You can likely shim up your pressure a bit closer to a lift capacity around 1750 but I would think 2000 might be really pushing it.

Unfortunately breaking your pallet down into 2 lifts is really the only way.
 

RIDETOEAT

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L4600, LA764, LP Blade,
Dec 26, 2014
132
0
0
Southern Indiana
Ya, I just wasn't willing to step up to the next chassis size. I got a QT pallet fork setup to try and keep it in close but still topped out at 1500 lbs ish and it was rated I think at 1725 lbs. 500 mm out from the pin so it's about right. I will let it all wear in a bit and after I make a ballast box I might test pressures and then ?? It sure would be nice to do 2000 but I am 25% off so too much to ask for all of that.