New loader valve not working properly

[Farmerford]

Fedup:

You supplied more than enough vitriol for all the posters; so we can limit posts to our feeble attempts to be helpful.

Perhaps you should avoid reading TBN since it upsets you.

 

[jd4310man]

Fedup: I spent a lot of time racking my brains and researching all kinds of different hydraulic components and comparing original stock machine specs to make this thing work. I am only trying to figure out why my loader circuit is giving me a problem. The machine drives, steers and runs well. I was hoping to find intelligent posters like J_J and Farmerford and the like to chime in and give me there opinions. Im not trying to start an argument.
Farmerford: I will post some pics tomorrow of the whole unit with the loader on. I had an idea on how to rout hoses and mount components but it all fell in place as I went along. There was a lot of figuring out one piece at a time. There isn't much room in this thing to work with. lots of hoses to deal with, but im overall happy with the outcome. Thanks for all the input Guys. Hear is a before pic of the machine. Also a couple after the diesel installation without the loader installed (center pics).

 

[J_J]

After reading back through all the info, you say you are using the SA valve to add the 7 GPM to the 14 GPM flowing to the motor valve.

Are all the valves open center valves?

Does the motor spool valves have a relief valve?

Is it possible that the motor valve fluid is causing back pressure to the loader valve?

How are you feeding the 7 GPM into the IN circuit on the motor valve. Is there a tee in the IN circuit.

Do you lock the SA valve to provide continuous flow?

If it is, you should add a check valve on the 7 GPM line to the tee.

What is the relief pressure on the stacked valve.

 

[jd4310man]

All the valves are open center. All valves have there own relief. I dont think that the motor valve is back feeding to the loader circuit as the spool is spring centered. You have to hold the spool open in order to get overdrive. It was only intended for intermittent use. There is a tee that the flow from the stack valve goes into the drive motor circuit. The relief pressure is set at 2000 psi on both attachment valves. I got to run it a bit yesterday, and its driving good but when you go to fill the bucket, it bogs down a bit. I works better when the fluid gets up to temp. I need to divert more flow to the attachment valve as Im probably not getting the full 7gpm to the valve.

 

[J_J]

I am a little confused as to where you want the fluid to go.

The loader will work on just about any GPM, the more you provide, the faster it will operate.

The same with the fluid for the drive motors, the more you provide the faster the machine will run.

Since most of your parts have about a 3000 psi rating, why not boost the relief pressure to 2500 psi or higher.

The pressure is what provides the torque or power. More pressure more torque.

Something else comes to mind. Since you have 7 GPM for the attachments and not used all the time, that potential HP is being wasted until you add that flow to the drive circuits.

Here is how I envision how it might work.

Bump up the pressure.

The other change I might make is to feed the flow from the stacked valve through a PB port and feed a tee with check valve at the input to the motor valve.

Now, you have the 14 GPM flow and the 7 GPM flow from the pump gong to the drive circuit, and when you use the attachments, the flow is reduced for the time you are using the loader. As soon as you release the loader lever, you are back up to speed on the drive motors.

 

[oldnslo]

JJ,
With the single pump he can't bump up the pressure. He does not have the HP available.

JD4310,
Can you put a gauge in the pump pressure line and also in the FEL valve inlet. I would be curious to see how much difference in pressure you are seeing between these two points.

 

[J_J]

Somehow, I was thinking the engine was 32 HP instead of 23 HP, but you are right, he is starting to run out of HP, speed and power.

Is the speed of the dozer satisfactory. I would prefer slower and more power.

By the way, I have the Magnatrack 1800 with a 16 HP engine turning a 5 speed gear box. I have a 25 HP Kohler engine I am thinking of installing whenever.

 

[jd4310man]

Actually, the speed might be a little fast for the available power. I should of got a smaller pump. But im learning by trial and error. But I wont know that for sure until I get the loader to work properly. I still cant turn up the divider valve like I want to. There is something causing a strain on the dump function. I was looking at these Magnatracs for quite some time and always wanted one. I also dreamed of re powering it with a diesel and modifying it to my needs. I could never see spending what they want for a new one and I finally found one used in good shape and everything is working out well. Im no engineer just trying to make something work. How do like the 1800? At least theirs less hydraulics to worry about on that one. I agree, slower and more power. Here is a few current pics of the machine.

 

[J_J]

On the M-1800 there is no hyd, just belts and a gear transmission. You brake one side to turn.

For raising and lowering implements, there is an electric LINEAR ACTUATOR motor on the front and back.

Do you have a large return hose on the loader valve and is it going direct to tank.

So you have the motor spool out/return hoses connected to the same return hose as the loader valve.

Have you looked at the pressure on each valve while using each valve and using both valves together, otherwise driving and loading.

If you take some pressure, readings, let us know what you see.

The two hyd circuits should be independent of each other.

If you reduce the flow to the hyd circuits, you should be able to raise the relief pressure and still be with in the HP of the engine.

Your 23 HP engine can support 12 GPM's, and 2800 psi.

Would you happen to have a hyd schematic of the dozer?

 

[jd4310man]

The return hose is the same diameter as the high pressure line, 1/2". The motor circuit is separate from the loader circuit. They each have their own return to tank. I don't have a gauge yet on system. Will be installing one soon. The stock motor pump had a displacement of .730 CI. and the attachment pump was .509 CI. That was a combined displacement of 1.239 CI. It was run by a 20 hp gas engine. Is running two smaller pumps easier on the engine than running one larger pump? Im thinking if I reduce the size of my current pump it will work better. Like gearing it down. Attached Is the stock Hydraulic diagram.