Also, it seems to me that guys in cooler climates tend to have more issues with regen than our southern friends. It has a much worse "word of mouth" reputation up here than in warmer places I've visited and folks here whine about the system more in the winter months.
Trying to understand specs
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TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Still a novice here but based on my usage over three MD winters my L3901 regens more frequently in colder months. Summer when most of the usage is mowing for xtended periods at 2500 RPM its roughly every 40 hours. That drops to about every 20 hours in winter when it gets more intermittent and lower RPM use. If I split a lot of wood interval goes back up.
I have never had a regen problem or anything to whine about. Regens just run concurrent with my usage - I just have to bump RPM up if it starts at too low a speed. I was a little unclear on how it the dash indications worked when I first read the manual. It became crystal clear the first time it did it. On two occasions I have had a regen start just as I was about to stop work. Bumped RPM up to 2500+ as indicated by the flashing lights, parked it and waited 5-10 minutes for it to complete before shutting it off. A real nothing burger.
YMMV,
Dan
I used to live a little east of you. I recall a cold night being +5 degrees (F) and being able to ride my motorcycle several days every month all winter long. Where I am now a cold night is -30 and there are many times when it doesn't get above 0 F for many days in a row. It doesn't snow much at -20, but snow still drifts. When I do have to move snow the engine barely gets warm and I don't want to hang out waiting for a regen (even if everything works perfectly, which locals tell me it does not). I opted for a pre-emissions model.
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Yes - northern climates pose significant challenges to diesel engines. I understand Dodge trucks commonly bump RPMS to keep temps up while idling at the curb. I can understand your preference for a pre- emissions model - makes perfect sense.
Fortunately I dont have to deal with the snow or temp challenges. We get maybe a week of 0F days per year here and I spend those inside. I opted for a new 38 HP TIER 4 tractor. I have had 50+ years worth of "fun" maintaing and repairing cars, trucks, and tractors. That's enough for me. This tractor will go to the dealer for anything other than minor service just like my hi-tech and my incredibly onerous to work on BMWs. I have nothing against turbos - just the opposite. I have been a turbo fan since i bought my 1983 Ford turbo coupe - first of 4. My daily driver is a twin turbo BME 335xi. Dead stock - no aftermarket tunes. If I wanted M class power I would buy an M.
I do have a fully equipped 3000 SF high bay "garage" and 1/3 of it contains the machine shop I mentioned earlier. It's warm and cozy in the winter and I get my fun designing and fabricating custom and NLA parts for old school Ford tractors. I have been doing that for 20+ years now. With the purchase of my L3901 I had started on some standard L Kubota projects but health issues have put those on my bucket list.
Stay warm and prosper,
Dan
Runs With Scissors
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L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
Can someone confirm this logic please:
So the hydro pump for the L2502 seems to be spec'd at 5.15 GPM @ 2205 PSI. If my maths are good, this is equal to 6.61HP. So this would explain why backhoe strenght would not change bweteen a 39HP or 25HP. Because the hydro only needs 6.61HP anyway ...
Does that make sense? Am I missing something?
So the hydro pump for the L2502 seems to be spec'd at 5.15 GPM @ 2205 PSI. If my maths are good, this is equal to 6.61HP. So this would explain why backhoe strenght would not change bweteen a 39HP or 25HP. Because the hydro only needs 6.61HP anyway ...
Does that make sense? Am I missing something?
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Yes you are missing something. The " strength" of the backhoe has nothing to do with tractor engine horsepower. It is a function of the hydraulic pressure it is getting from the tractor. If both tractors are operating at the same relief pressure there will be no difference in the lifting and breakout force of the back hoe.
Dan
Yes but pressure is a force, and force is HP in the end. A lawnmower engine wouldn't provide the power needed for that hydro pump. Right?
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
No. Horsepower is not force it is work. And work is force over time.
In the case of a hydraulic pump the horsepower needed varies directly with the flow rate. if output pressure remains constant and you double the speed of the pump it sinks twice as much horsepower. Your hydraulic force stays the same but you need more horsepower to run the pump at that higher flow rate.
F = PA
HP = (P X GPM)/1714
Dan
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ve9aa
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TG1860, BX2380 -backblade, bx2830 snowblower, fel, weight box,pallet forks,etc
Why do folks ask for help/advice, then argue with the knowledgeable/experienced folks giving it?
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Maybe because in some cases they need help understanding the initial answer. The physics abstraction of work confuses most people when they first see it.
Dan
Not arguing. Asking for clarifications ao I understand the answer. My question was more along the way of "this is how I think it works, I know I'm wrong, please help me understand why"
Correct, thank you. I actually knew that (honest!
)I guess what I meant is: is it correct to say that 25hp is more than enough to exerce a pressure of 2205 psi at a rate of 5.15GPM? Even a 10 HP engine would be able to achieve this. The force of the backhoe is determined by the pressure, but the time it takes to move the load is determined by the flow rate. So low pressure is a weak backhoe, low rate is a slow backhoe. So a 10hp engine could theoritically power the BH77 at the same strenght and speed. And this would explain why I'm being told that the L39 will make no difference on the backhoe over the L25. Am I wrong?
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Again the answer is no/maybe depending on exactly where your base number comes from. The HP formula I gave you was for an electric motor. The torque curves of electric motors are much different than internal combustion engines. So when calculating input HP needed for an internal combustion engIne you need double or more the HP of an electric motor.Correct, thank you. I actually knew that (honest!
I guess what I meant is: is it correct to say that 25hp is more than enough to exerce a pressure of 2205 psi at a rate of 5.15GPM? Even a 10 HP engine would be able to achieve this. The force of the backhoe is determined by the pressure, but the time it takes to move the load is determined by the flow rate. So low pressure is a weak backhoe, low rate is a slow backhoe. So a 10hp engine could theoritically power the BH77 at the same strenght and speed. And this would explain why I'm being told that the L39 will make no difference on the backhoe over the L25. Am I wrong?
Dan
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Not to get too terribly technical, power is the rate at which work is done (work divided by time). Work is force times displacement. For instance if a force is applied, regardless of how long, if displacement does not occur as a result of that force, no work has occurred.
The continuum beyond power is energy which is the rate at which power is provided, so ft-lbs/sec^2 or kW-Hrs (e.g. what you get charged for on your electric bill), would be examples.
The units of horsepower are ft-lbs/sec, specifically 1 Hp = 550 ft-lbs/sec. Apparently, a couple hundred years ago a fellow named James Watt determined this value approximated what a brewery draft horse could provide so that it could be used to rate steam engines. e.g. move 550 lbs 1 ft in 1 sec. Or 275 lbs 2 ft in 1 sec, etc.
It does appear there’s not any confusion that force, in a pressurized hydraulic system, is pressure times area (such as the area of a piston in a ram).
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Well, I'm pulling the plug on this. Just got a quote for the tradein and it would cost more than 25k. That's 10k more that what I expected.
So I'm keeping the b2601 but will be buying more toys for it. Will have to resort to renting equipment for atuborn stumps.
So I'm keeping the b2601 but will be buying more toys for it. Will have to resort to renting equipment for atuborn stumps.
You might see what you can get on the local used market? It sounds like you'll get 'er done either way. (the tasks, not the tractor swap)
^^^^
Agreed. Before giving up completely, I'd see what you might be able to get selling it privately. When I sold my B2601, I recovered all my costs (minus sales tax). And had I not honored the original deal I made with the gentleman that purchased it and sold it to the next guy right behind him, I would have made a profit on the sale. However, at the time, B2601's were incredibly hard to come by.
Mike
Agreed. Before giving up completely, I'd see what you might be able to get selling it privately. When I sold my B2601, I recovered all my costs (minus sales tax). And had I not honored the original deal I made with the gentleman that purchased it and sold it to the next guy right behind him, I would have made a profit on the sale. However, at the time, B2601's were incredibly hard to come by.
Mike
You may not get all that much benefit from an L2502 over a B2601 anyway. More tractor, yes. More work done.......not so clear.
I'm surprised at the price to change, but perhaps your B doesn't have a backhoe?
On your questions re: backhoe power, and ignoring some of the detail, yes in broad terms you're right. The backhoe on an L2502 is using only a portion of the power of the engine, it won't bog down no matter how hard you use the backhoe. The pump can only pump so much. And I think the pump on the L3902 is the same as on the L2502, so the extra HP is doing nothing extra for you. As to whether it's 10HP or 15HP that the pump is using, not sure. But it's not 25HP.