glennmac
Veteran Member
It has been suggested to me that, within a reasonable range, the lift capacity of a loader can be increased by raising the relief valve setting. Does anyone have any experience or comments on this.
Boosting FEL by Adjusting Relief Valve
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jdkid
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Hi Ya
is there a prob with your loader? get the PSI checked out frist if it's not doing what it should be doing .alot of FEL have 2 valves 1 on the tractor and one on the loader ,the one on the loader is so ya don't bend rams,blow seals etc etc the same for the tractor so ya don't pop "O" rings in the back end and over work Hydro pump .with nothing on the back (box blade etc or water etc in tires) most FEL will lift the back off the ground if things are going right if not maybe something is not working to max and dealer should be able to make better
catch ya
JD Kid
is there a prob with your loader? get the PSI checked out frist if it's not doing what it should be doing .alot of FEL have 2 valves 1 on the tractor and one on the loader ,the one on the loader is so ya don't bend rams,blow seals etc etc the same for the tractor so ya don't pop "O" rings in the back end and over work Hydro pump .with nothing on the back (box blade etc or water etc in tires) most FEL will lift the back off the ground if things are going right if not maybe something is not working to max and dealer should be able to make better
catch ya
JD Kid
No, there is nothing wrong with my FEL. The point of the suggestion was that, even if you had a "perfectly" factory set FEL, there is room to increase the rated lift capacity by increasing the factory relief valve setting. I don't know whether this is true, nor do I know whether this is a good idea. But it sounds appealing if there are no significant risks involved.
MChalkley
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Glenmac - Oh boy, another B-series owner asking questions... /w3tcompact/icons/laugh.gif
With my usual caveat, "I don't know nuthin' about 'em" firmly in mind, you can mull this over:
It most certainly can be done, and certainly has been done. Speaking hypothetically only, of course /w3tcompact/icons/wink.gif, the improvement in lift capacity is easily calculated. If you want, please provide the diameter of your cylinders, the rated pressure of your hydraulic system, and the manufacturer's listed loader capacity. I'll then reply with how much improvement you would see, in pounds of loader lift capacity, for an increase in pressure of 10-15% or so.
With the L-series tractors, they were once designed with a pressure relief valve in the 3-point hitch cylinder that would pop if too much pressure was applied to it. They don't have that valve in them anymore, so if you up the pressure too much, you can blow the piston right out of the transmission case, with the expense of the repair being the least of your worries! I don't know if the B-series tractors have a separate relief valve or not, but I doubt it. Either way, I definitely wouldn't recommend increasing the pressure more than 15%. Actually, I won't recommend you doing it at all, but you asked. It can be done, and it does help a lot. Hypothetically speaking, of course... /w3tcompact/icons/wink.gif
MarkC
With my usual caveat, "I don't know nuthin' about 'em" firmly in mind, you can mull this over:
It most certainly can be done, and certainly has been done. Speaking hypothetically only, of course /w3tcompact/icons/wink.gif, the improvement in lift capacity is easily calculated. If you want, please provide the diameter of your cylinders, the rated pressure of your hydraulic system, and the manufacturer's listed loader capacity. I'll then reply with how much improvement you would see, in pounds of loader lift capacity, for an increase in pressure of 10-15% or so.
With the L-series tractors, they were once designed with a pressure relief valve in the 3-point hitch cylinder that would pop if too much pressure was applied to it. They don't have that valve in them anymore, so if you up the pressure too much, you can blow the piston right out of the transmission case, with the expense of the repair being the least of your worries! I don't know if the B-series tractors have a separate relief valve or not, but I doubt it. Either way, I definitely wouldn't recommend increasing the pressure more than 15%. Actually, I won't recommend you doing it at all, but you asked. It can be done, and it does help a lot. Hypothetically speaking, of course... /w3tcompact/icons/wink.gif
MarkC
hayden
Veteran Member
Glenn,
Interesting idea. I've wondered about it too. I just looked and according to the manuals the tractor's hydraulic system pressure is between 1920 and 1990 PSI (that's the relief value setting spec). The loader's max pressure is 2000 PSI. Assuming all is operating as it's supposed to, the tractor's relief valve should be letting go first already, so jacking up the relief pressure on the loader will make no difference. You would have to increase both the tractor pressure and the loader pressure to get more lift.
Even if you could/did do it, I'd think it a bad idea since you are then exceeding the design loads for the loader components and structure. Granted, well engineered products have margin designed in, but you would at least be eating into that margin, not to mention increasing roll over risk, etc.
By the way, what has you looking to upgrade from the 2910?
Interesting idea. I've wondered about it too. I just looked and according to the manuals the tractor's hydraulic system pressure is between 1920 and 1990 PSI (that's the relief value setting spec). The loader's max pressure is 2000 PSI. Assuming all is operating as it's supposed to, the tractor's relief valve should be letting go first already, so jacking up the relief pressure on the loader will make no difference. You would have to increase both the tractor pressure and the loader pressure to get more lift.
Even if you could/did do it, I'd think it a bad idea since you are then exceeding the design loads for the loader components and structure. Granted, well engineered products have margin designed in, but you would at least be eating into that margin, not to mention increasing roll over risk, etc.
By the way, what has you looking to upgrade from the 2910?
Bird
Rest in Peace
glennmac, when I bought my B2710 it was sitting on the dealer's lot with no front end loader; he had to order the loader and install it. So I made the deal just going by the brochure and specs without actually trying a loader of that model. I had heard the same thing you've been told, so I told the salesman that I didn't know whether that was true or not on the B2710 with LA401 loader, but if so, that I wanted it set to the maximum factory spec. I told him when I pull back on that lever I want either the front end loader or the back wheels to come up in the air./w3tcompact/icons/laugh.gif Then I forgot to ever ask about it again, but I do know it would pick both back wheels right up off the ground with me on it.
Bird
Bird
I think Mark and Peter were typing their replies at the same time, but I have a hard time reconciling them. But, then again, I'm the guy who doesnt know what an impact wrench is.
Nevertheless, ignorance rarely deters me. My understanding is that when you are lifting something heavy with the FEL the fluid starts to "back up" and the pressure builds. At some pressure point set by the manufacturer, the relief valve releases the pressure causing the loader to stop lifting.
Now, it seems to me that there could be 3 reasons why a manufacturer would set the relief pressure at a certain point.
1. Further "backing up" pressure increases will harm or break or pop something inside the hydraulic system. This certainly seems likely at some extreme point, but I would expect there is a significant safety margin built in.
2. Further increases in pressure, allowing the loader to keep lifting, will somehow damage the mechanical structure of the loader. This seems much less likely to me than internal hydraulic damage--but, as I say, I really dont know.
3. Marketing reasons. As with many other products--eg, car engines, computers--the manufacturer sometimes "detunes" some functional widget in the product (ie, makes it run less powerfully than it can), just so the manufacturer can charge more for the widget when it is incorporated into a higher priced model. That's how product differentiation is sometimes created. For example, I believe one of Deere's loaders has a higher lift capacity on one tractor than another.
Now, again, I dont know whether any given tractor's loader relief valve is set for one or more of the above reasons. But it would seem to me that reason 1 would be the one to worry the most about and reason 3 the least.
Nevertheless, ignorance rarely deters me. My understanding is that when you are lifting something heavy with the FEL the fluid starts to "back up" and the pressure builds. At some pressure point set by the manufacturer, the relief valve releases the pressure causing the loader to stop lifting.
Now, it seems to me that there could be 3 reasons why a manufacturer would set the relief pressure at a certain point.
1. Further "backing up" pressure increases will harm or break or pop something inside the hydraulic system. This certainly seems likely at some extreme point, but I would expect there is a significant safety margin built in.
2. Further increases in pressure, allowing the loader to keep lifting, will somehow damage the mechanical structure of the loader. This seems much less likely to me than internal hydraulic damage--but, as I say, I really dont know.
3. Marketing reasons. As with many other products--eg, car engines, computers--the manufacturer sometimes "detunes" some functional widget in the product (ie, makes it run less powerfully than it can), just so the manufacturer can charge more for the widget when it is incorporated into a higher priced model. That's how product differentiation is sometimes created. For example, I believe one of Deere's loaders has a higher lift capacity on one tractor than another.
Now, again, I dont know whether any given tractor's loader relief valve is set for one or more of the above reasons. But it would seem to me that reason 1 would be the one to worry the most about and reason 3 the least.
MChalkley
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Glenn,
There is a main system relief valve and, frequently, a relief valve in the loader valve block, as well. So, as Peter said, you would have to up the pressure setting in both to get greater loader lift capacity.
As for the reasons for the relief valves, every component has a design limit, or even compromise points. The pump, for example, may have a maximum pressure rating of 3,000 psi, but it will last a lot longer if the maximum pressure it generates is limited to 2,500 psi. So, more is involved than just breaking or not breaking things. Other things, like cylinders, also have pressure limits on seals, etc. Still, as I said, the tolerances are such that 15% should be very safe. At least, nobody I know has ever had any problems from increasing the pressure that much.
MarkC
There is a main system relief valve and, frequently, a relief valve in the loader valve block, as well. So, as Peter said, you would have to up the pressure setting in both to get greater loader lift capacity.
As for the reasons for the relief valves, every component has a design limit, or even compromise points. The pump, for example, may have a maximum pressure rating of 3,000 psi, but it will last a lot longer if the maximum pressure it generates is limited to 2,500 psi. So, more is involved than just breaking or not breaking things. Other things, like cylinders, also have pressure limits on seals, etc. Still, as I said, the tolerances are such that 15% should be very safe. At least, nobody I know has ever had any problems from increasing the pressure that much.
MarkC
jdkid
Gold Member
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- 8350 valmet with 980SL FEL duels had a 150 Hp deutz just sold it 10 NOV 01
Hi ya
oh ok ,yep like most things with abit of working ya can get more power ,lift ,speed etc etc and with addon's even more most people have played with V8's carbs,headers etc etc to get more out of things even some tractors one motor can go from 100 hp -170 hp the motor in my tractor starts at 135hp and with addons 260hp .now FEL keep in mind it's a addon ,the lift involves not just the hyrdo psi . tractor sub frame,loader frame,loader arms and rams,front axle etc etc .other thing i'd sooner see is the loader kick out lower than tractor ie the loader valve let's go frist not the tractor .other way of getting higher lifting/brake out psi is bigger rams( all my FEL's run 3 inch rams).... in short would i lift the psi on mine NO but i would put bigger rams on if i needed more lifting power
catch ya
JD Kid
oh ok ,yep like most things with abit of working ya can get more power ,lift ,speed etc etc and with addon's even more most people have played with V8's carbs,headers etc etc to get more out of things even some tractors one motor can go from 100 hp -170 hp the motor in my tractor starts at 135hp and with addons 260hp .now FEL keep in mind it's a addon ,the lift involves not just the hyrdo psi . tractor sub frame,loader frame,loader arms and rams,front axle etc etc .other thing i'd sooner see is the loader kick out lower than tractor ie the loader valve let's go frist not the tractor .other way of getting higher lifting/brake out psi is bigger rams( all my FEL's run 3 inch rams).... in short would i lift the psi on mine NO but i would put bigger rams on if i needed more lifting power
catch ya
JD Kid
allmobile
Bronze Member
Just restating what has already been said. You should have no problem increasing the system and loader relief 10-15%.
Brian
Brian