I am planning on adding a Fischer snow plow to my Deere 310L. I can obviously use the front end loader controls to raise and lower the plow blade, and angle it up and down. The used plow came with two hydraulic cylinders to angle the plow side to side. I'm wondering how they work, as I am a total novice on hydro design. If there are two cylinders that move the plow - left and right, does the opposing cylinder move the other back in the original direction when it engages? For example, I angle the plow to the left, so the right cylinder elongates. What keeps it there, and prevents the snow from pushing the blade back? Is it a check valve, or continuous hydro pressure from the pump? And when I go to angle it back to the center or to the right, does the other cylinder move the blade, while the opposing cylinder lets loose somehow? Thanks
I think most truck snow plows use 2 single acting cylinders to angle the blade. Kind of like you described. Not sure but some might have a safety feature to prevent damage if you hit something solid. The plow might be designed to push with it either straight or angled all the way to either side. How much and how dense the snow is might dictate how much the blade can be angled. I think you'd have to use the electric pump the plow came with to angle it. Using the machine hyd's wouldn't be worth the trouble and be way too fast to boot. I'd guess the blade has a spring trip but mounted on a backhoe I'd wonder if you'd be limited in how much you can push before the blade trips? How big of a truck did the plow come off and how wide is it? If it's off a pickup truck might not stand up mounted on a much heavier backhoe.
You need another circuit on the machine to angle the plow. The cylinders are cross plumbed so that oil going to the rod side on one cylinder also goes to the piston side on the other cylinder. Circuit reliefs hold the oil in place unless a large force pushes oil pressure higher than the relief valve pressure.
What model of plow is it or looking at the cylinders, do they have ports at each end or only one port at the back of the cylinder body? Some Fisher plows use single acting cylinders with 1 hose to each cylinder and some use double acting cylinders with 2 hoses to each cylinder. To use your machine hyd's. for angling you'd need to install flow restrictors so you didn't slam the cylinders to full angle the instant you moved the valve.
Contact the supplier/manufacturer and ask them for a hydraulic schematic for the plow hookups as a first step.?
If i were you, I'd get a dedicated plow for loaders. A lot of guys have destroyed plow frames because they use the tilt function on accident. Loader plows are configured differently. Just my .02c
Depending on the plow, I think having it on a backhoe could have the potential to do some serious damage to the plow or the frame. If the plow is off a 5 ton truck might be fine but off a 3/4 or 1 ton ton truck might not be sturdy enough.
The plow will angle side to side, so there's no need for the tilt function on a snow plow, you could put quick couplers on the tilt hoses and hook up the angle cylinders to that function. You can wreck a plow with a backhoe, but you might be fine if you're careful with it and the releases work. The hydraulics will work fine hooked straight to the tilt function, maybe fast like Dave said, but you can add an orifice easily at any point if you want it slowed down. The valve holds the fluid until you move the control valve to let oil flow each way.
Being careful is the key word!
I bought the plow for $100, and the machine shop will put another $100 into it to fix the small spots of rot. I plan on moving very slowly, and being very careful. It’s not as if I am plowing parking lots or miles of road.
The angle cylinders have one hydro connection point, so I assume that fluid fills the chamber and air on the other side of the cylinder chamber gets forced out. The opposing side then compresses that cylinder back when the plow angles the other way. Thanks for clueing me in on the existence of a hydro schematic.
I think I'd use the electric over hydraulics. Altering the backhoe for more functions will NOT be simple! A problem with plows on a backhoe is a combination of balance & the distance from front tires to plow. Front wheels tend to slip sideways. Another problem is the loader pivot angle is all wrong to push snow. You need to have the floating pivot very near the ground. I mounted one so the pivot was as far to rear as I could. Leave the boom rigid except raising the plow off the ground. I did not like the set up & only used it with blade not angled. I've kicked around the idea of a snow pusher. I think that'd work better.
Willie made a lot of good points about plowing snow. The cylinders are most likely one way, think of it as the rod is the only piston, oil goes into the cylinder and forces the rod out. If the rod is pushed back into the cylinder, then oil must escape. One hose to each cylinder, and the rod will be nearly as large as the inside diameter of the cylinder. The cylinders push against each other like you said, there is no pull back, only force one way. If the cylinders are two way, they'll have two hose connections to each cylinder and each hose will be connected to both cylinders, only criss crossed. On ag stuff, you'll sometimes see a two way cylinder used with only one hose, and a vent on the other end to release the air and any leaked oil, but a snowplow will have purpose built one way cylinders and won't have that air inside the other part of the cylinder.
It has single acting cylinders which is OK but I agree it would be much simpler to use the electric power pack to angle the blade. Would have to see it but some parts may need reinforcement to stand up to the backhoe. $100 is certainly a good deal.
Can you explain further? I know there’s an issue with the filled bucket lifting weight off the front wheels when in float. Distance? Balance? Pivot near the ground? What pivot?
To push snow, a plow has to scrape it from solid earth. The direction of thrust must be nearly parallel with earth. otherwise the first little bump or obstacle turns the plow into a pole vault. Plenty of people, myself included have replaced a loader bucket with a plow on a farm tractor. The plow must float to follow the ground, but pivoting high (typically 5' above the ground) makes it constantly grab the ground & the tractor tries to climb over the plow. Setting the loader frame stiff & setting the plow up with its pivot free to move eliminates the problem. As for distance from front tires & a light front end, the plow has a lot of leverage if angled to push the backhoe sideways. Take the same tractor, remove the weight of the backhoe, or match the weight on the front tires it behaves much better. I see few backhoes in the 14000 LB to 18000 LB range outfitted with snowplows, but many with snow pushers. A snow pusher does not angle. It is typically 6' wider than a plow on a comparable machine. It will have a rubber cutting edge that rides over irregular pavement. I put a power angle plow on a Case 580K four wheel drive backhoe weighing 16400 LBS. Even with chains on all four tires, behavior was dissappointing.
Would it make sense to put beet juice in the front tires to add front weight?
I think a backhoe would be plenty heavy enough.
Excellent explanation. Thank you.
I believe it would help, but a backhoe center of gravity is pretty far to rear. If the bucket is still attached, something very heavy in the bucket would be in order. Simple truth is a backhoe is not the best snow plowing rig. A pickup weighing half as much is far superior for plowing. I do use a backhoe for snow removal because I do 6 residential driveways where the ability to scoop buckets of snow is nice. I have the 9' plow rig, but haven't installed it in over ten years.
Beet juice is not enough to make a difference. Backhoes have large loaders on the front, and still need cast iron weights added to the front end. Willie is right, he's done it, I'm just speculating, but I've seen plenty of backhoes doing wheelies. Entirely wrong weight distribution, angle plowing will be disappointing. Pushing straight works fine on flat ground with traction.
I run a converted plow on my skid steer, it's a heavy duty truck plow. I angle it with the machine hydraulics and if you have a circuit available I'm going to go against popular opinion here and suggest you use it. Electrical systems on tractors and machines are not generally robust and an electro-hydraulic pump will tax it heavily. You can add flow restriction valves to the plow hoses to keep the angle speed manageable and you'll need a crossover relief valve to absorb shocks if you hit something. The crossover valve will allow the plow to give if you hit an obstruction rather than blowing a hose, and angle cylinder of valve seals. It might sound complicated but it really isn't.
I get that a hoe is not the best snow plow choice, but it's what I have, and I'd rather use that instead of my riding tractor snow blower since the hoe is heated. I have two, 275 foot driveways, so it's not as if I'm going to be plowing parking lots or roads. It seemed that last year, the wind blew the snowblower snow onto my face and head, soaking me to the bone. The idea of sitting in a heated cab, and making one pass in 5 minutes seems like an improvement.
By all means. If you choose to plow with a hoe, it's a fine thing to do. It is what I use. I choose to use the bucket, but would love a snow pusher. My driveways are easy to do with bucket, I'd also like a 2 yard bucket. One problem I see is most of my driveways are a single plane. They tilt for drainage, but are flat. The cutting edge of a loader bucket is always parallel to the rear tires. Tilted or not, a flat surface works fine with a loader. My next door neighbor has a driveway sort of a bowl shape. It tilts toward the ditch along the paved road enough to drain, but probably 2' higher on edges than center 30 feet wide, 80 feet long. To further complicate, the town road is 7% grade at that spot. It seems there is always one corner of the bucket digging into the ground while the other side is inches above. A snow pusher able to float left to right would work better in that circumstance. A plow works fine, but way out in front far enough to clear a bucket when angled makes it very prone to sliding the tractor sideways instead of pushing the snow sideways. You'll use it nearly square to the tractor to control that. I've made a lifelong search for the perfect combination of free & perfect snow removal. Best I ever had was a 1976 Jeep (full sized) Cherokee with 360, 4 speed, rear locker, & 8' Fisher plow. Four tire chains are a must.