Importing and modifying a new mini excavator from China

[LouNY]

A suction strainer is a very important part of a system it will protect your pump from large debri that could destroy a pump.
A return filter with a bypass will help to maintain clean hydraulic fluid.

 

[D'oh]

I agree with the Strainer Filter being very important., It Directly protects the Pump from any debris that gets into the Tank, the Spin On Return Filter cleans the Oil that has already gone all through your system.

A 10 Micron In Tank (Suction) would diminish Flow Rates, so I would leave the 100 Micron In Tank the way it is.

When I put my Plow Truck through the Ice, Insurance wrote off my Truck but not my Plow. I drained the Pump (which was clean anyways) of water, however the Swing 1 way Cylinders, actual had water in them that took many Oil Changes to get the water out.

Once anything is In, it takes alot to get it out.

 

[dfkrug]

Most of our tractors come with a steel mesh 100u suction filter in the bottom of the hydraulic oil sump. It does keep the manufacturing debris out of the pump, which is good.

However, it can cause problems, too. Esp when you get water in the oil, which is very hard to remove. I have had a few tractors that I acquired with water in the oil. This problem can be especially bad when starting the machine in sub-freezing weather, where water emulsion has frozen solid on the suction filter mesh. In that case, suction can cause pump cavitation, and even collapse and break the suction filter into pieces.

 

[Rich B1]

I am not trying to start an argument….just relating personal experience with suction strainers,

I spent my entire career (43 years) working for a company that built excavators. I spent a lot of those years heavily involved with hydraulic troubleshooting.

I came to loathe suction strainers on any type of suction line attached to a pump. Mainly due to lack of maintenance issues, but also due to inherent cavitation on some piston pump installations that could go from stand by flow (6 - 8 GPM) to near full flow (80+ GPM) very rapidly. The pump failure could be rather catastrophic from the cavitation over time.

Eventually, our pump supplier quietly dropped the requirement for suction strainers. And pumps quit failing.

 

[jaylast]

^^ I wonder how applicable cavitation is for these comparable tiny gear pumps?
Makes sense imo to have something to trap anything foreign right where it's introduced. Even just a screen in fill hole.

Brandonb, which are you considering, agt?
Here's pics of my stock one from diggit (nuoman, leking).
It might not flow full return well- this one is filtering 2 functions of 8 but I guess all fluid eventually goes thru it. Same premise as a cooler that cools but doesn't restrict full flow.
Translate shows the manufacturer- might be helpful to whomever you are buying from. It's beside the slew motor on the 'firewall'

 

[D'oh]

I could see that happening with a Piston Pump, but the Gear type Pumps that we have, Starvation would be better than What Ever going through the Pump. No 43 years of experience but 9 Years in Farm Machinery and -35F temps

 

[jaylast]

You can certainly move some of the functions around by switching hoses

Thinking of doing this for Boom and bucket to test the theory. Boom shouldn't feel the touchiest when it's the largest cylinder

 

[dfkrug]

Thinking of doing this for Boom and bucket to test the theory. Boom shouldn't feel the touchiest when it's the largest cylinder

I switched mine cuz I am used to the ISO pattern, which my backhoe has.

The boom control is quite jerky cuz it is very heavy, relative to total machine weight, and the flow rate is too high.

The lift force with the boom is amazingly high with the RV set properly (2400-2500psi). There are many test demonstration vids on Utube now, and one shows one of these 1.2-1.5T minis lifting another mini.

 

[Agitator]

For what it's worth - and hoping to add to the general bank of knowledge here: I figured out the root of the my machine's engine fading & surging / lack of power was. It turns out that it was fuel starvation. Once my gas tank gets to be 1/3 full or less, the fuel flow is really unreliable - especially since my entire property is hilly, so there's no really level area where I'm working. The gas was sloshing in the tank and it just wasn't getting the fuel it needed. For the moment, I'm making sure it's got a full tank, but I've ordered a small electric fuel pump online and will be installing that, tied to the ignition switch. Don't know if anyone else has needed to do that, but thought it would be worth mentioning.

If anyone has done that, and has particular wisdom to share about how to shoehorn it in, I'd love to hear about it...

 

[dfkrug]

For what it's worth - and hoping to add to the general bank of knowledge here: I figured out the root of the my machine's engine fading & surging / lack of power was. It turns out that it was fuel starvation. Once my gas tank gets to be 1/3 full or less, the fuel flow is really unreliable - especially since my entire property is hilly, so there's no really level area where I'm working. The gas was sloshing in the tank and it just wasn't getting the fuel it needed. For the moment, I'm making sure it's got a full tank, but I've ordered a small electric fuel pump online and will be installing that, tied to the ignition switch. Don't know if anyone else has needed to do that, but thought it would be worth mentioning.

If anyone has done that, and has particular wisdom to share about how to shoehorn it in, I'd love to hear about it...

I certainly have encountered fuel starvation in the past, as I operate on steep hills all the time. I try to bring along a little fuel each time I go back to my worksite, so the tank does not run low. I can go a long time on just a gallon of gas.

If you use an electric fuel pump, you will still need to use the fuel outlet at the bottom of the tank. Same problem.

Note that if you let heat inside the house get out of control, the gas will actually boil, and that may exacerbate the problem.