Flail Mower Let's talk flail mowers

[IslandTractor]

Island Tractor, If the fluid in a hydraulic close loop is prevented to circulate, the fluid will overheat. Take the case of my flail mower extender cylinder connected to the auxiliary control valve (a close loop system). Assuming I move the selector to B (see picture) and the cylinder extends to full travel, at this point it becomes a dead end for the oil (no return path to the sump). Pump pressure will build up in Port B as long as the selector is left in position B. To prevent an excessive pressure buildup the main relief valve will open, and bleed some oil back to the sump. However since the relief valve is a flow restrictor the oil will quickly overheat. With my Kioti 30 HST hydraulic system I will need to return the selector to N (Neutral) as soon as the cylinder has reached full extension or retraction. I had a firsthand bad experience with this phenomenon just after buying my tractor from an estate sale. No one was able to explain to me the peculiarity of the tractor and the closest dealer was more than 2 hours away from my location. I decided to remove the backhoe to service the tractor. I used the book that came with the backhoe to find the procedure, and followed the instructions to the letter. Upon removing the backhoe, I shut the tractor off and bled the pressure from the hydraulic lines by exercising each backhoe control lever. Then I disconnected the quick disconnects from Ports A and B at the back of the tractor (nowhere in the book did it mention to set the hydraulic selector to neutral). I restarted the tractor and pulled away, and drove it for almost 15 minutes until I saw smoke coming out of the Power Steering Unit (I had previously removed the instrument panel cover). I touched the steering unit and burnt my fingers. After talking with the dealer I understood the problem. By disconnecting Ports A and B without setting the auxiliary control lever to Neutral, I had interrupted the closed loop circuit and hence caused the relief valve to open and the oil to overheat. I immediately replaced the HST fluid and filters. So far the tractor has not displayed any permanent damage to the hydraulic system. I hope some (hydraulic) newbie will learn from of my mistake. Andre <img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=457682"/><img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=457683"/>

You are describing "deadheading" a hydraulic pump. I was using the term closed loop to describe a typical hydraulic circuit.

 

[Cataclysm]

Just scored an 8' flail off CL for $250 cash. From this thread it looks like an Alamo.

The good: All the bearings turn freely with no slack. 'Y' knives look great. All the seals look good with no leaks. Gear box seems tight.

The bad. Needs a drive shaft and needs the metal sides that hold the back roller reworked. And from reading on here a fresh belt.

Current plan is to rework it enough to make sure it a good unit then a functional rebuild and paint to match my up coming LS 4155HC.

Any guesses if the 55hp LS will run it?

In my area no one hardly even knows what a flail mower is. This is the first one Ive ever seen in person

Oh and thanks to everyone who posted in this thread. I learned a lot and it has inspired me to give this flail a try.

 

[Alien]

In my area no one hardly even knows what a flail mower is. This is the first one Ive ever seen in person

Same here. But after lots of research I decided it was the only way to go. Have fun.

 

[sodamo]

Sounds like a good deal. If I ever saw one for that price here on CL it would likely be ready for the scrap yard. Took me less than 2 hrs to sell my Value Leader on CL and when the guy picked it up and paid me he remarked what a great deal it was. He has been rehabbing and selling tractors/implements over 20 years here.

David Sent from my iPad Air using TractorByNet

 

[leonz]

Just scored an 8' flail off CL for $250 cash. From this thread it looks like an Alamo.

The good: All the bearings turn freely with no slack. 'Y' knives look great. All the seals look good with no leaks. Gear box seems tight.

The bad. Needs a drive shaft and needs the metal sides that hold the back roller reworked. And from reading on here a fresh belt.

Current plan is to rework it enough to make sure it a good unit then a functional rebuild and paint to match my up coming LS 4155HC.

Any guesses if the 55hp LS will run it?

In my area no one hardly even knows what a flail mower is. This is the first one Ive ever seen in person

I will post pics when I figure out how.

Oh and thanks to everyone who posted in this thread. I learned a lot and it has inspired me to give this flail a try.

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I want to welcome you as the newest member of the flail mower nations; no passport is required to enter or leave the beer garden at the border crossing nor are there any member address rosters kept or nor taxes collected-HATE BLACK HELICOPTERS.

You are among friends so ask any questions about flail mowers that you think you need to ask. NO you do not need the PTO Shafts with the slip clutches for this flail mower.


Your LS should have no problems powering the flail mower you have as long as you spend the time needed reading how you should operate your tractor at much lower speeds when mowing in high grass/brush. I will be back later.....




Please order a catalog from flail master as you will be able to obtain most rear roller parts for most models from them rather than having them fabricated locally.


Be sure to buy the kevlar replacement belts for it. they are more shock resistant than the black V belts

 

[Kiotidriver]

You are describing "deadheading" a hydraulic pump. I was using the term closed loop to describe a typical hydraulic circuit.

Island Tractor
泥ead-heading the system occurs when the fluid in a system is prevented from flowing and the pressure in the system reaches a maximum value.
Therefore I dead-headed my hydraulic pump when I disconnected the lines from my backhoe without setting the Auxiliary Control Valve to Neutral, and the same would happens if I was to actuate a cylinder using the ACV rear ports and keeping the pressure on the cylinder piston. The point I知 trying to make is if you stop the flow of oil in a closed loop, you will be dead-heading the pump. I don稚 think we are disagreeing on this point? Are we?

PS: I didn't really dead-head the pump because the relief valve opened.

 

[IslandTractor]

Island Tractor
“Dead-heading” the system occurs when the fluid in a system is prevented from flowing and the pressure in the system reaches a maximum value.
Therefore I dead-headed my hydraulic pump when I disconnected the lines from my backhoe without setting the Auxiliary Control Valve to Neutral, and the same would happens if I was to actuate a cylinder using the ACV rear ports and keeping the pressure on the cylinder piston. The point I’m trying to make is if you stop the flow of oil in a closed loop, you will be dead-heading the pump. I don’t think we are disagreeing on this point? Are we?

Agree. But the only way to stop the flow is to "deadhead". If I attach a simple loop from one port to the other that doesn't deadhead. Indeed, to prevent what you did, the simplest solution is to have a short piece of hose with appropriate male QCs on each side and simply plug those into the ports that the BH uses. Then it doesn't matter if you forget to change the position of the remote control lever.

 

[Kiotidriver]

Agree. But the only way to stop the flow is to "deadhead". If I attach a simple loop from one port to the other that doesn't deadhead. Indeed, to prevent what you did, the simplest solution is to have a short piece of hose with appropriate male QCs on each side and simply plug those into the ports that the BH uses. Then it doesn't matter if you forget to change the position of the remote control lever.

Great suggestion! I will just do that. Thank you very much

 

[Cataclysm]

======================================================================


I want to welcome you as the newest member of the flail mower nations; no passport is required to enter or leave the beer garden at the border crossing nor are there any member address rosters kept or nor taxes collected-HATE BLACK HELICOPTERS.

You are among friends so ask any questions about flail mowers that you think you need to ask. NO you do not need the PTO Shafts with the slip clutches for this flail mower.


Your LS should have no problems powering the flail mower you have as long as you spend the time needed reading how you should operate your tractor at much lower speeds when mowing in high grass/brush. I will be back later.....




Please order a catalog from flail master as you will be able to obtain most rear roller parts for most models from them rather than having them fabricated locally.


Be sure to buy the kevlar replacement belts for it. they are more shock resistant than the black V belts

Thanks for the info! I can't wait to get the belt cover off and see if there is a data plate! I think the mower would work now with a DS but the passenger side roller bearing looks to be in a bind and I don't want to kill it.

 

[IslandTractor]

Great suggestion! I will just do that. Thank you very much

FYI, I made mine with about 12 inches of 1/4" hose, 90 degree angle and necessary 1/4 to 3/8 adapters to 1/2 Pioneer QC male fittings. That gives you a flexible small length of hose that lays flat against the back of the tractor rather than sticking out where it could snag. I'll try to find a photo.