MF 175 Extra Hydraulic Circuit

[Ohtuckian2025]

I have a 1968 MF 175 tractor that has a front loader on it. It has 2 single acting cylinders to raise and lower the front loader and a double acting cylinder to curl the bucket. I just recently purchased a Grizzly BH105 that requires another hydraulic circuit. I would like another circuit to operate it without having to unhook the hoses for the bucket curl and then hook up the backhoe. I am looking at a 3-way selector valve part number 185644 on tractorpartsasap.com and I would like to know if I can use this part or part number 161564 to add an extra hydraulic circuit. The description says it adds 2 ports, but I'm not sure if that's what I need or not. I put in a call to Marcus at Yesterday's Tractors on Thursday and he was going to check on it but I haven't heard back yet. If you can help me I would appreciate it.

 

[Jim.ME]

185644 valve appears to be a TISCO TS300 valve and the 161564 is a similar valve with different port angles. Those valves bolt on to the right front corner of the hydraulic lift shaft cover (aka rock shaft cover). They tap into the three-point system hydraulics with is the 4.5 to 5 GPM pump. It is a kind of diverter valve. Below are the instructions that come with a TS300. It will give you one pressure port to supply the backhoe, and you will have to establish a return port for the backhoe return hose elsewhere on the tractor to return fluid to the transmission/differential case. The handle would be to the rear for this as it will be supplying the control valve for double acting cylinders. Your tractor's inner quadrant lever will need to be in the constant pumping position and the outer one to the rear (I think) to send full time oil flow to the backhoe. Again, this is using the small hydraulic pump (lower flow) and you have to follow the instruction to shift the TS300 back to the right position for the 3-point to work. The hoe and 3-point will not work at the same time with those valves. You could use the front port to run your single acting loader lift cylinders and convert the auxiliary system single acting rear remote to double acting for the backhoe if you want more hydraulic flow for the backhoe. Having the bucket lift on the other valve again means either the loader or the 3-point at a time.

 

[Ohtuckian2025]

185644 valve appears to be a TISCO TS300 valve and the 161564 is a similar valve with different port angles. Those valves bolt on to the right front corner of the hydraulic lift shaft cover (aka rock shaft cover). They tap into the three-point system hydraulics with is the 4.5 to 5 GPM pump. It is a kind of diverter valve. Below are the instructions that come with a TS300. It will give you one pressure port to supply the backhoe, and you will have to establish a return port for the backhoe return hose elsewhere on the tractor to return fluid to the transmission/differential case. The handle would be to the rear for this as it will be supplying the control valve for double acting cylinders. Your tractor's inner quadrant lever will need to be in the constant pumping position and the outer one to the rear (I think) to send full time oil flow to the backhoe. Again, this is using the small hydraulic pump (lower flow) and you have to follow the instruction to shift the TS300 back to the right position for the 3-point to work. The hoe and 3-point will not work at the same time with those valves. You could use the front port to run your single acting loader lift cylinders and convert the auxiliary system single acting rear remote to double acting for the backhoe if you want more hydraulic flow for the backhoe. Having the bucket lift on the other valve again means either the loader or the 3-point at a time.

View attachment 140590

Thank you for your clear and concise response. I was thinking that would be the way it works but I wanted to ask someone for sure. You helped me with the hydraulic flow problem I had reported on another issue. I think for now I'll just hook the hoses up as I need them. It's not like I'll be using it every day.

 

[Ohtuckian2025]

The controls for the loader are down at my RH side to the right of the seat. For me, that's kind of awkward. I would like to get a 2 spool valve and weld a bracket on the loader arm on the RH side, but where would I get hydraulic fluid from? Could I tap into the hydraulic lines that are routed to the existing 2 spool control valve? I'm afraid using the above mentioned valves won't supply enough hydraulic pressure/volume. Please advise and thank you. You mentioned I wouldn't have oil return if I use the diverter valve mentioned above, also.

 

[cjunrau]

There are a couple ways to ad the spool on the loader arm. I have done it a few times and I won't say it was done the right way but it works for me.
In the back of your tractor you have the tilt and/or lift cylinders plugged in. One of those circuits is what I used. I plug the in and out of the spool you mount on the loader into there. Then when you want to use the loader just pull the correct lever back and have a hook or something to keep it there. that gives you oil to the spool on the loader, when doing this you must know what direction the oil is going so that you go in on the in side and out on the out side. It will have the same volume and pressure as it has now.
The correct way on most tractors is to tie in to the spool it already has. so if there is an out hose on the spool on the tractor that is where you run a hose to that goes to the in side of your mounted spool. the out side of your mounted spool goes to where the out on the existing spool hose went.

The out on all spools just dumps the oil free flow into oil reservoir or rear end if not a separate reservoir.

 

[Ohtuckian2025]

Thanks, but I don't want to do it that way. I'm looking for a way to do it so I'm not always plugging and unplugging hoses.