Importing and modifying a new mini excavator from China

[dfkrug]

If I did go with a smaller pump, the cylinders moving slower would be good, and of course the pressure would be the same but what effect do you think the reduced flow would have on my track drive motor power? Would the torque be the same and just move slower or would I lose power as well?

Torque at the drive sprockets is a function of hydraulic pressure and motor volume. Pretty much the only time I have stalled the drive sprockets (system RV opens) is when I get a rock jammed in the tracks.

Now POWER at the sprockets (actual work done-speed) is a factor of pressure and flow, but your engine can deliver more power at higher RPM, versus at lower RPM.

If you look at the power curve for a 420cc gas engine, you may see something like 10hp at 3000 RPM, and 15hp at 3600. So, running the engine faster to get higher flow with a smaller pump would deliver more work (power) to the drive sprockets.

A smaller pump would allow you to run the engine slower in less-than-maximum demand situations. This "sweet spot" is about 3000RPM. 2000RPM for any of the diesels, 1-3cyl.

 

[HCS-II]

In a previous post, I had surmised that the Diggit EM15 OEM may be LeKing but the track base and slew tower is different between the EM15 and LeKing's KV13 Plus. Just found out the the Diggit EM15's OEM is Shandong Jianggong Machinery Co. (SDJG) and they market this model in their own brand lineup as the JG-15: JG-15 Mini Excavator-Mini Excavator-Shandong Jianggong Machinery Co., Ltd. Hope this info can be useful to other EM15 owners.

 

[D'oh]

They look to be the same as FF15's that are running through the auctions here also

 

[dfkrug]

Diggit EM15's OEM is Shandong Jianggong Machinery Co. (SDJG) and they market this model in their own brand lineup as the JG-15:

Sure looks like it. Owners should try to contact them and get info on the hydraulic system, including the pilot control pressure and test port. I see their website offers an email address and a contact window.

 

[HCS-II]

They look to be the same as FF15's that are running through the auctions here also

When looking closely at the machines the FF15 seems to be a different beast altogether: shorter tracks (180x72x37 and two bottom idler rollers for the FF15 vs. 180x72x41 and three bottom idler rollers for the EM15), boom is not the same design (FF15 has similar designs as other FF Industrial and AGT machines), foot controls are different, left joystick console does not lift (safety cutoff is a manual toggle switch instead of being integral to the lift of the console on the EM15), FF15 has less ventilation holes as the EM15, electrical cut-off switch mounted on the left joystick console instead of the the kickplate under the seat (better design IMO), different front blade, different roof and support structure, comes with a manual thumb while the EM15 has none as standard issue, no aux. lines shutoff valves on the dipper, etc...

I honestly don't know who manufactures the FF15 but it doesn't look like its a standard product from LeKing or SDJG.

 

[HCS-II]

Sure looks like it. Owners should try to contact them and get info on the hydraulic system, including the pilot control pressure and test port. I see their website offers an email address and a contact window.

I will most likely contact them to enquire about availability of replacement parts like pumps and hydraulic motors. Aside from pilote control relief pressure and tests port location, what other information would you like to get?

 

[dfkrug]

I will most likely contact them to enquire about availability of replacement parts like pumps and hydraulic motors. Aside from pilote control relief pressure and tests port location, what other information would you like to get?

I am curious if that unit has return filtration, and if it is the same as on the EM15, which does need an upgrade to something better with a spin-on replaceable filter.

Anyone who buys one should definitely open it up to see how it works.

 

[D'oh]

When looking closely at the machines the FF15 seems to be a different beast altogether: shorter tracks (180x72x37 and two bottom idler rollers for the FF15 vs. 180x72x41 and three bottom idler rollers for the EM15), boom is not the same design (FF15 has similar designs as other FF Industrial and AGT machines), foot controls are different, left joystick console does not lift (safety cutoff is a manual toggle switch instead of being integral to the lift of the console on the EM15), FF15 has less ventilation holes as the EM15, electrical cut-off switch mounted on the left joystick console instead of the the kickplate under the seat (better design IMO), different front blade, different roof and support structure, comes with a manual thumb while the EM15 has none as standard issue, no aux. lines shutoff valves on the dipper, etc...

I honestly don't know who manufactures the FF15 but it doesn't look like its a standard product from LeKing or SDJG.

Good Eye, But I like the B&S in the FF-15.

Is the Track Tension on the Diggit EM15 a Grease type or Bolt?

 

[HCS-II]

Good Eye, But I like the B&S in the FF-15.

Is the Track Tension on the Diggit EM15 a Grease type or Bolt?

Bolt type. Waiting for the last fittings to arrive to complete my hyd. filter and cooler install and then will be able to share pictures. Seller of the cooler on AliExpress told me the fittings where BSPP but when I received it it required BSPT! Well, another two-weeks delay...

 

[JohnnyB24]

In a previous post, I had surmised that the Diggit EM15 OEM may be LeKing but the track base and slew tower is different between the EM15 and LeKing's KV13 Plus. Just found out the the Diggit EM15's OEM is Shandong Jianggong Machinery Co. (SDJG) and they market this model in their own brand lineup as the JG-15: JG-15 Mini Excavator-Mini Excavator-Shandong Jianggong Machinery Co., Ltd. Hope this info can be useful to other EM15 owners.

Thanks, that is some very good info. Mine looks the same only it's branded as a Miva VA15. I would love to get a part number for the return filter inside the reservoir. I do plan to change it to an external spin on in the future but that may be at the same time I install a new lower output pump. From the specs listed, it looks like the existing pump is 10.6GPM. I would love to have something around 8GPM.

I have about 13 hours on it so far and I'm very happy with it. As long as I run it just above idle it's very smooth. On to the next project!

 

[dfkrug]

As long as I run it just above idle it's very smooth.

Nice looking paver job. Aren't you concerned about frost heave where you are?

 

[Carl_NH]

Agree that's a nice patio/fireplace install. As far as frost heave not a lot you can do as it goes down 3-4'. As long as you have a 6" or so gravel base, then 2" compacted tillings/stone dust and sand on top it's about all you can do. Appears he excavated about a foot or so..

It will freeze and flex - you just need enough uniform material to allow for movement - our brick walkways will heave a bit in the winter, but the main patio 20 x 40 area doesnt appear to move much at all.

 

[JohnnyB24]

Nice looking paver job. Aren't you concerned about frost heave where you are?

Yes, the frost line is around 4 feet here. It will freeze and move some but the key is to excavate the black dirt and organic material then add 4-6 inches of class 5 and compact it as you go. Then screed 1 inch of bedding sand and lay pavers. I also do not use polymeric sand for the joints as it's not good at flexing.

I have a few single family rental homes and my next excavator project is replacing an old retaining wall at another house. That machine is really paying for itself.

Pic is after the black dirt was out and crushed limestone was in.

 

[HCS-II]

Thanks, that is some very good info. Mine looks the same only it's branded as a Miva VA15. I would love to get a part number for the return filter inside the reservoir. I do plan to change it to an external spin on in the future but that may be at the same time I install a new lower output pump. From the specs listed, it looks like the existing pump is 10.6GPM. I would love to have something around 8GPM.

I have about 13 hours on it so far and I'm very happy with it. As long as I run it just above idle it's very smooth. On to the next project!

The filter inside the reservoir is not a return filter but rather a coarse oil pickup screen. You normally don't need to change these much. A return oil filter is a good idea. I'm waiting on a few fittings to do an oil filter and cooler install. Jury is still out as to where I move the return line manifold (currently right at the behind the hydraulic reservoir). I can either move the manifold to connect to the output of the blue safety solenoid (but it would be supported by the pump body which is exposed to the engine's vibration) or move the solenoid and manifold between the valve body and battery under the left step board (it would then hang from the valve body and be isolated from the engine's vibration).

EDIT: I just checked my EM15 and it does have both a return filter as well as a supply screen in the tank. If you install a 25micron return filter on the return line, I would leave the return filter in the tank. It probably helps the oil from foaming and would never get dirty if a 25 micron filter is installed before it. If you install a coller, you want to put it between your external filter and the tank so it sees the least amount of pressure.

 

[Flyfisherar]

When looking closely at the machines the FF15 seems to be a different beast altogether: shorter tracks (180x72x37 and two bottom idler rollers for the FF15 vs. 180x72x41 and three bottom idler rollers for the EM15), boom is not the same design (FF15 has similar designs as other FF Industrial and AGT machines), foot controls are different, left joystick console does not lift (safety cutoff is a manual toggle switch instead of being integral to the lift of the console on the EM15), FF15 has less ventilation holes as the EM15, electrical cut-off switch mounted on the left joystick console instead of the the kickplate under the seat (better design IMO), different front blade, different roof and support structure, comes with a manual thumb while the EM15 has none as standard issue, no aux. lines shutoff valves on the dipper, etc...

I honestly don't know who manufactures the FF15 but it doesn't look like its a standard product from LeKing or SDJG.

I also have a FF15 and would like to find an operation manual. Is your FF15 made by FF Industrial? There doesnt seem to be any website for FF Industrial and when looking for information I always end up @AGT?

 

[HCS-II]

I also have a FF15 and would like to find an operation manual. Is your FF15 made by FF Industrial? There doesnt seem to be any website for FF Industrial and when looking for information I always end up @AGT?

Sorry, I don't own a FF15 but instead a Diggit EM15. I talked about the FF15 as one user commented that they looked the same...same metal cowling but when you compare the FF15 and the EM15 (AKA the OEM's JG-15), we can note significant differences. I unfortunately don't know who manufactures the FF Industrial machines but I also note always seeing them at auctions in the company of AGT machines.

 

[brandonb]

I've been slowly modifying and improving my little excavator. I recently wondered if it was possible to have the light switches illuminate when in the ON position. I popped a switch out of the dash and disassembled it and was surprised to see an LED and resistor installed. I'm not an electrical person and have no idea how I would get this work or if it's even possible?

Can anyone help me?

 

[LittleBill21]

I've been slowly modifying and improving my little excavator. I recently wondered if it was possible to have the light switches illuminate when in the ON position. I popped a switch out of the dash and disassembled it and was surprised to see an LED and resistor installed. I'm not an electrical person and have no idea how I would get this work or if it's even possible?

Can anyone help me?

one of the terminals prolly needs 12v applied to it for it to light up

 

[dfkrug]

I recently wondered if it was possible to have the light switches illuminate when in the ON position. I popped a switch out of the dash and disassembled it and was surprised to see an LED and resistor installed.

First, you have to find out what you have.

Looks like a 4-terminal switch. Is the diode/resistor connected only to the 2 unused terminals, and only to them?

If that is the case, you need to connect both unused terminals to the other side's terminals (respectively). It will only work in one of the 2 possible configurations. Since you have a diode in the circuit, current only goes one way.

Try that and report back.

 

[JohnnyB24]

I've been slowly modifying and improving my little excavator. I recently wondered if it was possible to have the light switches illuminate when in the ON position. I popped a switch out of the dash and disassembled it and was surprised to see an LED and resistor installed. I'm not an electrical person and have no idea how I would get this work or if it's even possible?

Can anyone help me?

Using your existing switch and having it illuminate when turned on requires another terminal that you don't have and a wire connected to ground for the LED current.

Maybe the easiest, although not the cheapest, way to accomplish this is to just get a different switch. I quickly found one on Amazon that has some options for when the LED is lit and one of the pics has an easy to follow wiring diagram. You will have to add a wire from the switch to ground to provide a return current path for the LED though.

At $25 It's not cheap but you do get 8 of them for future use and it comes with some easy to use jumper wires, cool overlays, and other stuff.

The third pic is what I think you have now and how you could mod your switch, that seems impractical but not impossible.

Getting a different switch is just one option.