RC4WD 4200xl digger questions

[Simon Weel]

So I got myself a 4200xl. And its been sitting on my table for a little over two weeks - the radio didn't work correctly. Last week, I received a new one from RC4WD and so I could finally get going! That's the time for those "Hey, why is this...." questions. So here we go with a couple of those questions and I hope to get some answers.

I switch on the radio, plug in the digger-battery. Switch on the oil pump, and notice it hardly turns. Hmm. Looks like the relieve valve isn't working. When operating the boom, the pump spins up to a decent speed, but as soon as I let go of the sticks, it nearly halts. That's not good, so I switch off the pump. I flip all switches on the radio and when flipping the gear-switch (top front right on the radio), I hear a valve servo move. Turns out this switch controls the relieve valve. When I then switch on the pump, it runs almost ok. But the gear-switch isn't supposed to operate the relieve valve - this is controlled by some mixes on the radio. When I select 'Display' on the radio and move the sticks, the bar for the relieve valve doesn't do anything. When I flip the gear-switch, the bar is permanently on. Also, when the oil pump runs, it speeds up when I move the boom. Rather odd. After some fiddling, I found out I had to reverse AUX for channel 8. Flip the gear switch back and now the pump runs much faster when idling and slows down when moving the boom. As you would expect. I opened up the broken radio and found out the gear switch isn't connected. There are two wires soldered to the middle pin. On the new radio, it isn't?

Next thing is the control style. I swapped the wires for channel 1 and 4 on the receiver to get the CAT / Euro style of control. Now the bucket is operated with the right stick and turning with the left one. Subsequently, I had to reverse the setting for channel 4 (Rud), so moving the stick left will make turn left. And I had to reverse one of the track channels (channel 7 aux in this case) so both tracks move in the same direction when moving the track levers in the same direction. But now, when I plug in the battery, it immediately starts turning? I have to switch on the radio first. No big deal, just something to remind.

Having that sorted out, it's time to do some digging! That is, I have to learn to control it. When operating the boom, I notice it moves a bit slow. No problem for a digger apprentice, but in time I guess you want it to move a bit faster. I notice the radio's E.point for the pump (the first flp) is set to 23%, so it runs on about a quarter of its nominal speed. If I increase the speed, this will increase the working pressure and so the boom will operate more swiftly. Question is: can it handle this increased pressure?

The sticks on the radio. Some movements are quite sensitive and others aren't. I checked the radio's manual for sensitivity settings, but besides being translated to proper Chinglish, it doesn't do much explaining on all it's settings....

That's enough for now, time to practice my digging skills! Speaking of which, is there some kind of manual on how to operate a digger? Or is it just a matter of doing it?