3rd Function on Mahindra 4350

[irsmun]

There are steel lines from the pump that connect to 1/2 hoses then to the loader valve. I am assuming hoses and the steel lines are the same size but I don't really know the ID of the hoses. Its then 1/2 hoses from the loader valve to the same size steel lines to the rear and the power beyond. 3/8 hoses to the FEL and 1/4 to the cylinders.

 

[J_J]

If 3/8 in hose are going to the FEL, then the flow is limited by the flow coming from the FEL.

So if the FEL is using 3/8 in hose then what is the problem with using DO3 3/8 in ports?

Have you had any problems with heat so far?

This should have been an easy workup for this project.

 

[irsmun]

It should have been easy but you are having to deal with my ignorance also.

Because the PB hose is 1/2 and, if I understand this right, the subplate for the 3rd function will be routed right in the middle of this hose. Yes, 3/8 to the FEL. But now you have reduced the once 1/2 PB hose to the rear to a 3/8 via the P and T port. Right?

Its not the connection to the loader I am addressing. Its the flow to the 3pt via the PB line. That will have a 3/8 in the middle unless I get a subplate with 1/2 P and T ports. It looks like to me I am squeezing my PB line flow down to 3/8 from 1/2 and the back to 1/2 after the subplate.

Please correct me if I am not seeing this right.

 

[J_J]

The limiting flow in your hyd flow path has been answered, and by adding a 3/8 in DO3 subplate you are not really losing much.

The 3pt will still get the same flow as before.

 

[irsmun]

So you are saying that my flow rate will stay the same throughout the system but it will simply speed up and increase in pressure in the 3/8 section of the subplate. So my guess is that as long as the subplate can handle this extra pressure and dissipate the heat properly then I shouldn't notice any changes in performance?

JJ, you are one patient man. and just so you know I have learned a lot from this thread.

 

[J_J]

There are two ways to check your flow.

A good flow meter.

A 5 gal bucket and time the flow with engine at max rpm and using which ever hose you want.

One gal of flow in 6 seconds would be 10 GPM.

 

[irsmun]

I think I will be happy if someone who has installed one of the kits chimes in as to their subplate size vs their input/output hose size. I don't need to blaze this trail. Its already been done. I just need verification before I do it to MY tractor. When watching the install videos on youtube, I don't remember them mentioning hose sizes.

You didn't answer my question. When a larger pipe flows into a smaller pipe then either the pressure has to increase or the flow rate. The difference in 1/2 verses 3/8 is significant in a diameter. Add to that the pressures we are talking about here and something has to happen. Remember, I didn't just want to talk about this so someone could tell me what to do. I wanted to learn through the process and hopefully help other hydro-ignorant newbies. So I guess I am trying to get an explanation of why this reduction doesn't affect the circuit.

JJ, I take it you are older than me. You are welcome to hit me with your hat. :confused3:

 

[J_J]

The pump is still trying to pump the flow dictated by the engine rpm, and when you reduce the flow by decreasing the port size, the flow will decrease and the flow velocity will increase, therefore increasing heat.

If the system can tolerate the heat increase, then it is not a big problem.

So by reducing the flow through the FEL using 3/8 in hose, and then add another 3/8 port subplate in series, the heat goes up, but then again, if the system can handle it , then no big problem.

You are already using the 3/8 hose from the FEL to supply the rest of the hyd system, and even if the flow is reduced to the 3pt, that only affects speed. The cyl will still develop the pressure.

So I say this again, if the hyd system has been working all this time with the FEL using 3/8 hose, it should still work OK.

For a base line measurement, before you install the new valve, take some temp readings of the hyd fluid after a good work out, and use that to compare that after the new valve install.

Your 3pt will work the same.

Even the engineers don't get it right the first time, they usually have to have the technicians work out all the problems.

 

[irsmun]

Ah... which explains why the subplates are usually large aluminum blocks. They are heatsinks as well. So is the pump giving consistent PSI but varied flow rates based on engine rpms? or is both the flow rate and the PSI varying according to the engine speed?

 

[J_J]

The hyd flow is in GPM's.

The pump is rated for a certain pressure, but it is the resistance to the flow such as fluid flowing into a cyl or hyd motor which develops the pressure.

 

[Wook660]

I had/have a lot of the same questions you are having. I was concerned about reducing from 1/2 to 3/8 and back to 1/2 through my subplate for the same reasons you are. Don't forget, though, that even if the D03 subplate you were using had 1/2 inch connections, you would still be flowing through the same small holes in your solenoid valve. Unfortunately I have had no time to even use my tractor since installing everything besides cycling everything and checking for leaks, but the system seems fine. I'm just going to have to keep an eye on the heat, but like you said, this isn't the first time this has been done. I'll try to get some pictures tonight of where I located everything if I can.

 

[irsmun]

I knew others have had these questions that's why I didn't mind looking like the stupid one to ask them out loud.

I do realize about the 3/8s to the FEL but the subplate functions essentially as a T. I was more concerned with what was happening to the PB line going through the subpate. I think its clear to me now. There was a function of hydraulics I was not understanding and that was that the "pressure" line is not holding 3000psi at all times, only when a load is applied.

I want to see pics of your install especially how you ran your lines through your loader. Mine are pretty tight.

 

[Wook660]

Routing the lines was not easy, it was super tight! I think I'll have time to get some pictures for you tomorrow.

 

[irsmun]

Ok, I have all parts in hand or on order. I have the valve mounted and the connecting hoses ran. I am compiling pictures to document my install on a different thread. I do have a question. When I put the new lines in do I have to bleed the air out of the hoses or will that be pushed out and released within the circuit somehow?

 

[MtnViewRanch]

No bleeding should be required.

 

[Wook660]

That will bleed out on its own as you run the cylinders through their motions. It may seem kind of notchy at first, at least mine did, but it shouldn't take long to get back to normal after a few cycles. The pump is getting a constant supply of fluid so it will push out any air. I took a few pictures with my phone the other night of my set up but they came out horrible so I never posted them.
Did you run the new lines with the loader lines? That was tight, huh? What are you using to control the valve? I modified a winch control for mine:

 

[irsmun]

I have not run the long lines to the loader yet. They are on order. If I bought them locally I'd have to mortgage my home. Hydraulic prices are ridiculous.

I am not running mine through the loader on the same side. I am running them through the other side. I installed my valve under the dash behind the detachable kickplate. You cannot even tell I did anything. Its all hidden. I love it. I want a smooth factory looking install. No lines or valves strangely attached to things. When I get it finished I am going to document it in a new thread. Everyone is asking the same questions and I hope my experience will help others who had the same questions I had.

I haven't decided on a control yet but I know I won't be buying one...again ridiculous. Its just a SPDT momentary rocker switch mounted in a handle. I am all for people making money on their items but it seems a bit steep. Right now I am considering buying an oversized automotive shifter knob and mounting the switch in it.

 

[J_J]

Have all the questions in your original post been answered?

 

[irsmun]

I think so. This has been so enlightening to me. I understand plumbing (water) and electricity. I just wasn't getting the total concepts of hydraulics that related to it specifically. You have been a great help and thanks for your free knowledge. I feel confident enough in what I've learned to post my install for others to see.

 

[irsmun]

I have everything hooked up and I have a two leaks. One I think just needs tightening or thread sealer. But the other one is confusing me. It is leaking around the ball in the quick connect. I thought the pressure would seal it. Do I have a bad coupler or what?