SNOW PLOW

[CSHELTONSOON]

HELLO, I HAVE JUST MOUNTED A SNOW PLOW BLADE ON MY BOBCAT 763 AND ARE HAVING PROBLEMS WITH THE HYD. THE PLOW WAS WORKING FINE WHEN I TOOK IT OF MY TRUCK. AFTER I MOUNTED IT TO THE LOADER I HOOKED UP THE HOSES TO THE AUX HYD. ON THE LOADER ,STARTED THE MACHINE AND ANGLED THE BLADE TO THE LEFT. IT ANGLED BUT WOULD NOT ANGLE TO THE RIGHT. I SWITCH THE HOSES AND IT MADE NO DIFFERENCE. IT SEEMS I'M GETTING PRESSURE TO THE HOSES. DOES ANYONE HAVE ANY ADVICE ON WHAT THE PROBLEM COULD BE. THANKS

 

[TriHonu]

Well a description of how you have the plow plumbed would help.
Does your plow have two single acting cylinders? Did you attach one hose from the Aux to one cylinder and one hose from the other Aux to the other cylinder?
If so are you turning on the Momentary Auxiliary operation and then using the rocker switch on the operator side of the right handle?
Other questions are:
Have you tried to operate other hydraulic attachments to determine if the Aux is working?
What series is this loader? (C, F, or G)
If you remove the hoses from the cylinders can you angle the blade by hand?

 

[CSHELTONSOON]

Well a description of how you have the plow plumbed would help.
Does your plow have two single acting cylinders? Did you attach one hose from the Aux to one cylinder and one hose from the other Aux to the other cylinder?
If so are you turning on the Momentary Auxiliary operation and then using the rocker switch on the operator side of the right handle?
Other questions are:
Have you tried to operate other hydraulic attachments to determine if the Aux is working?
What series is this loader? (C, F, or G)
If you remove the hoses from the cylinders can you angle the blade by hand?

Thanks for your reply, The plow does have two single cylinder and I adapted the fittings on the hoses and connected them to the aux. hyd. on the loader. I hit the Aux. Hyd. button once and then hit the toggle switch to the left and the blade jerked to the Left. Moved toggle switch to the right and the blade jerked to the right about an inch and stopped. I then disconnected the hoses and broke lose the fittings and was able to move the blade back and forth. I pulled and inspeceted all the quick couplers for any obstructions, they were clear. With hoses from the Aux Hyd on the machine open I operated the toggle switch and observed that I was getting good plow thru both hoses. I then reversed the hoses and reconnected. I then moved the toggle switch to the left and the blade jerked to the right. Moved the toggle to the left again and the blade jerked all the way to right, mved the toggle to the right and the blade moved about an inch to the left and stopped. The machine is a 96 or 98 763, I dont know what series it is. It is like the Hyd. fluid is not being released from the extended cylinder. Thanks for your help.

 

[skidsteer.ca]

Thanks for your reply, The plow does have two single cylinder and I adapted the fittings on the hoses and connected them to the aux. hyd. on the loader. I hit the Aux. Hyd. button once and then hit the toggle switch to the left and the blade jerked to the Left. Moved toggle switch to the right and the blade jerked to the right about an inch and stopped. I then disconnected the hoses and broke lose the fittings and was able to move the blade back and forth. I pulled and inspeceted all the quick couplers for any obstructions, they were clear. With hoses from the Aux Hyd on the machine open I operated the toggle switch and observed that I was getting good plow thru both hoses. I then reversed the hoses and reconnected. I then moved the toggle switch to the left and the blade jerked to the right. Moved the toggle to the left again and the blade jerked all the way to right, mved the toggle to the right and the blade moved about an inch to the left and stopped. The machine is a 96 or 98 763, I dont know what series it is. It is like the Hyd. fluid is not being released from the extended cylinder. Thanks for your help.

You have one hose from each cylinder connected to a separate coupler on the loader? Nothing T'd together?
If you loosen the line the right cylinder then the blade will angle that direction?
Ken

 

[CSHELTONSOON]

You have one hose from each cylinder connected to a separate coupler on the loader? Nothing T'd together?
If you loosen the line the right cylinder then the blade will angle that direction?
Ken

Nothing tied together, seperate hoses. Crack lose the fittings and the blade will move

 

[TriHonu]

Nothing tied together, seperate hoses. Crack lose the fittings and the blade will move

Two more questions.
1. When you removed all the couplers and checked them did you connect plow male to loader female and plow female to loader male and while connected blow through them to insure the as mounted pairs of couplers allow good flow?
2. When you "Reversed the lines and reconnected" did you swap the hoses at the cylinders or did you swap the couplers on the plow hoses?

If you swapped the hoses at the plow cylinders it looks like you have a restriction on the right side keeping the fluid from returning to tank. This could be a bad coupler.
You can test this by angling the blade to the left and then removing the coupler from the right plow hose. Put the hose in a clean bucket, clamp the hose to the bucket and put a cover over the bucket. Be careful as the oil will be squirting hard. Make sure it can not shoot your direction. Try to angle the blade to the right. If the plow angles and fluid from the right cylinder is in the bucket then either the coupler is bad or a spool valve is not opening to allow the fluid back to the tank.
Do you have a double acting cylinder that you could attach to the Aux to test for proper pressure and return in both directions?

 

[TriHonu]

Two more questions.
1. When you removed all the couplers and checked them did you connect plow male to loader female and plow female to loader male and while connected blow through them to insure the as mounted pairs of couplers allow good flow?
2. When you "Reversed the lines and reconnected" did you swap the hoses at the cylinders or did you swap the couplers on the plow hoses?

If you swapped the hoses at the plow cylinders it looks like you have a restriction on the right side keeping the fluid from returning to tank. This could be a bad coupler.
You can test this by angling the blade to the left and then removing the coupler from the right plow hose. Put the hose in a clean bucket, clamp the hose to the bucket and put a cover over the bucket. Be careful as the oil will be squirting hard. Make sure it can not shoot your direction. Try to angle the blade to the right. If the plow angles and fluid from the right cylinder is in the bucket then either the coupler is bad or a spool valve is not opening to allow the fluid back to the tank.
Do you have a double acting cylinder that you could attach to the Aux to test for proper pressure and return in both directions?

Also, to make your posts easier to read, login and then select Profile from the menu.
Next check the box next to: "Use HTML Editor (Free Text Box)".
You will then be able to add some line breaks and will be able to use the other formatting tools.

 

[skidsteer.ca]

Also, to make your posts easier to read, login and then select Profile from the menu.
Next check the box next to: "Use HTML Editor (Free Text Box)".
You will then be able to add some line breaks and will be able to use the other formatting tools.

I'm thinking coupler problem too. I'm pretty sure its the same spool (it is on a G series) in the valve that moves to send oil out on one coupler that also lets oil return to the tank on the opposite coupler.
Try removing both the loader coupler and coupler from the right hose,conect them and see if you can blow through them both ways.
Ken

 

[CSHELTONSOON]

Also, to make your posts easier to read, login and then select Profile from the menu.
Next check the box next to: "Use HTML Editor (Free Text Box)".
You will then be able to add some line breaks and will be able to use the other formatting tools.

Thanks, As advised I angled the blade to the left and disconnected the hose on the right cylinder and secured end in a plastic jug. Fired up the machine, hit the aux. hyd. button, moved the toggle switch to the right and the blade moved all the way to the full ext. of the ram. Hooked back up hoses, moved toggle switch to the left and blade moved all the way to the left. Moved toggle switch to the right and once again moved only about and inch and stopped. Would not move either way after that. Disconnected all quick couplers from hoses and machine, reconnected together and blew thru them both ways, all clear. Three out of the four couplers I just purchased new this week. Do you have any other suggestions ? Thanks

 

[TriHonu]

Thanks, As advised I angled the blade to the left and disconnected the hose on the right cylinder and secured end in a plastic jug. Fired up the machine, hit the aux. hyd. button, moved the toggle switch to the right and the blade moved all the way to the full ext. of the ram. Hooked back up hoses, moved toggle switch to the left and blade moved all the way to the left. Moved toggle switch to the right and once again moved only about and inch and stopped. Would not move either way after that. Disconnected all quick couplers from hoses and machine, reconnected together and blew thru them both ways, all clear. Three out of the four couplers I just purchased new this week. Do you have any other suggestions ? Thanks

It seems that the oil returning to tank from the right plow cylinder is being blocked. Yet you still have pressurized oil flowing to the right cylinder.
You stated you replaced three couplers. What was wrong with the three you replaced?
It almost makes me wonder if there is a piece of something sealing the flow going back to tank but allowing the flow going out to the coupler.
If you removed the aux line at the hydraulic valve that is attached to the right plow cylinder, you could check for return flow through the loader lines.
If there is flow there, then the problem is in the aux spool/ports in the valve itself. If no flow at valve then there is some restriction in the aux line.

 

[CSHELTONSOON]

It seems that the oil returning to tank from the right plow cylinder is being blocked. Yet you still have pressurized oil flowing to the right cylinder.
You stated you replaced three couplers. What was wrong with the three you replaced?
It almost makes me wonder if there is a piece of something sealing the flow going back to tank but allowing the flow going out to the coupler.
If you removed the aux line at the hydraulic valve that is attached to the right plow cylinder, you could check for return flow through the loader lines.
If there is flow there, then the problem is in the aux spool/ports in the valve itself. If no flow at valve then there is some restriction in the aux line.

Thanks, I put two of the new couplers on the snow plow lines so the would connect to the Loader quick connects, the third coupler was for the loader itself, I was having a hard time connecting the old one. I have owned the machine for seven years and have ever used the Aux. Hyd. How do I find the hyd. valve that feeds the aux. hyd. lines ? Thanks.

 

[TriHonu]

Thanks, I put two of the new couplers on the snow plow lines so the would connect to the Loader quick connects, the third coupler was for the loader itself, I was having a hard time connecting the old one. I have owned the machine for seven years and have ever used the Aux. Hyd. How do I find the hyd. valve that feeds the aux. hyd. lines ? Thanks.

You have to raise the cab to get to the hydraulic valve. It is the center of the loader on the drivers right side. You can't miss it.
You can download the 763 manual from HERE. For now you probably just need the hydraulic chapter. There is also a Hydraulic Tests manual for the 743 on the same site.

 

[CSHELTONSOON]

You have to raise the cab to get to the hydraulic valve. It is the center of the loader on the drivers right side. You can't miss it.
You can download the 763 manual from HERE. For now you probably just need the hydraulic chapter. There is also a Hydraulic Tests manual for the 743 on the same site.

Thank you for your help. Happy Holidays.