rc4wd excavator

[andyathome]

I have a small problem that I need a little help with.

I decided to let my kids and their mate play with my excavator.
That was the start of a few problems, someone decided to play with the radio settings....

So far I've managed to get it running but it has no power in the hydraulics, it's almost like the mix switch is turned on.
Have checked the operation of the switch and I can see it turning on , on the radio.
The pump speed is good but no power, I can see the 4th valve move with stick movement of the cylinders.
Have checked all the obvious to me things, like oil level, pump direction ect
I am at a loss, any help would be appreciated.

Cheers andy

[Dieselchopper]

check the pump esc speed. The dial towards top of radio and settings for that can really change machine performance.

[daddycool75]

Hi Andy,

Check your setting on the other forum....

http://australian-rc-truck.proboards...cavator?page=2

Cheers

Jamie

[andyathome]

Thanks guys for the replies.

I got some more story's last night about what happened , and it sounds like someone also turned up the pump speed to a million miles an hour , and was using it for a while before my oldest removed the radio from him and shut it down.
It's a shame you can't leagaly beat someone else's child.

All is good in the radio department, but still no power and slow.
I'm going to swap the valve bank for the new set I intended to use in the Kat and see what happens

Cheers andy

[chris deacon]

Is the hydraulic oil coming back to tank when not using any hydraulics? Is there any way that they could have adjusted the throw of the 4th valve somehow?

[andyathome]

I can see oil in the return line to the tank, from the prv but dosent apear to be flowing and also can see the 4th valve move when other valves move.
But from memory last night it looked like the 4th valve was opening , not closing when the others opened
The pump seems to labour with stick movements, so I'm hopeing it's a set up issue with the 4th valve.

Will have another look when I get home.

Cheers andy

[chris deacon]

Yeah sounds like it. Maybe needs re-centering

[daddycool75]

I had a similar problem, it was a bit of dirt in the return line to the tank!!!

It had me scratching my head for days.

I would take the return line off and check the flow to the tank.

Cheers

Jamie

[andyathome]

Well, some time in the shed .
And a result.
After rechecking everything again I could not fault it yet still no power and no leaks .
So I replaced the valve block and servos.
I have dropped motor speed from 23% to 18% and have truck loads of power and a very quite motor/pump.
I will have a play later today but I think I could probably go even lower on motor rpm.
I think the valve seals must have ruptured inside due to max motor rpm , but will pull valves apart and check.
This is the original valve block since new, so maybe 3 years old, I've also noticed my cylinders don't move now after pump is turned off, so I guess the valves were on their way out anyway.

Cheers andy