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tman1986
01-20-2012, 03:41 PM
Hey i just got my first excavator and i have a couple question's about the hydraulic system that hopeully someone here will be able to help me out with

1. is it possible to put too much oil in the system, is there suppose to be some air (as cylinder volume isn't the same both ways) in the resevoir, for instance i put oil in with all cylinders while they where compressed, ran it, put more oil in with cylinder extended ran it, but notice drop in power and that my resevoir would actually move from im guessing pressure build up when the cyinders compressed, i allowed a bit of oil to come out the breather and power was increased but im not sure about what im doing here... any tips would be great

in other words how do i know when i have enough oil in my hydrualic system

2.whats the proper way to use the breather on my resevoir i know what it does but what is it's purpose, is it simply for relieving pressure for opening the system, or is it vital in the proper function of the machine while it's running
again any tips would be greatly appreciated

i may have some more Q's in the near future but i figured i would start here as ive read through many many forums and threads but could not find specific answers to these questions

The machine im talking about is the rc4wd earth digger btw i was sceptical about purchasing it cause it's from china i thought the quality wouldn't be up to par with other models but i must say every aspect of this machine greatly exceeded my expectations, i haven't seen much written about it by anyone who bought one here or anywhere for that matter so if anyone has any Q's about it i would be more then happy to answer

just a bit about it,
i was told i got version 1.5 it's valve block is different from most i've seen it's 3 spool but has 4 servos one is switch operated to relieve some pressure in the system along with the main pump switch make's it seem pretty efficient, one way for show and moving the boom around almost zero strain on motor, flip the switch and full power through the pressure valve for digging, i thought that was neat and unexpected, sorry i had to mention it

Thanks for any and all replies
Trevor

RCP57
01-20-2012, 07:24 PM
I'm not sure what your tank looks like but there should be some free space for sure. (maybe 2/3 full) Also your vent must be open during operation so that no pressure or vaccum developes in the tank. Someone may chime in with more info on this though.

Where are the pictures of this thing???? I would like to see a pic of this new valve setup.

Reg

fhhhstix
01-20-2012, 07:43 PM
As you retract the cylinder the rod takes up space and not as much fluid is needed to move the piston as what is needed to extend the cylinder. The level of the fluid in the tank will go up and down with these actions. You should have some air space in the tank when the excavator is in the ready position (boom up with the stick strait up and down). In this position the cylinders should be close to half stroke. As RCP57 said the breather should be open so the tank doesn't build up pressure or vacuum (what it does) which will cause the pump to labor or the tank to collapse or explode if it is not open (the purpose).


Travis

tman1986
01-20-2012, 08:44 PM
hey thanks for the help, really appreciate it

heres some pics of the hydraulic system, i dont really know how to post them so i just attached them

see the fourth servo nearest the tank thats the one i was mentioning

also notice in the pic of the front/side of the valve block there are 2 outputs that loop through the filter and "T" joint before going back to the tank, just seems like that is hosed wierd, your opinions would be a great help

and i would like to mount a pressure gauge in this system i think the best place is right between the pump outlet and the valve block inlet (black hose beside clear center pic) but again your opinions would help my decision making alot easier

Thanks again
Trevor

fhhhstix
01-20-2012, 08:58 PM
I am thinking the clear line from the valves to the T then to the tank is the open return from valves or the loop which is oil that is not used and just passes through the valves as the standby pressure which doesn't have to be filtered. The black line from the valves to the filter and then to the T is the return oil from the cylinders which needs to be filtered before returning to tank. This is a good way to keep the flow going when the machine is at rest and not cause unnecessary heat build up. However if heat is not an issue a secondary filter to filter all of the return oil would not be a bad idea. If heat does become an issue an oil cooler can be added.

Travis

steamer
01-21-2012, 12:04 PM
Trevor, in the middle picture it looks like there are electrical wires going to the silver valve on the return line. If they are wires, that's possibly the valve that dumping the pressure when you don't need it . Is the radio programed to do this or is it a manual thing. If possible can you take a picture of the pump as that looks like a new setup too.
Rob

tman1986
01-21-2012, 08:34 PM
Hey, heres a couple more pics

there are no wires coming from the silver "T" on the return line or anywhere else but the 4 servos and the motor in the hyd. system i took a better pic so you can see the 4th servo that drops the pressure diectly across from the pump it is switch operated not automatic

im wondering where on this system the actual pressure valve is, like where i can adjust it from, im begining to think the vavle block is two pieces and the pressure valve is in the part that connects directly to the pump, i might have to wait till i can hook up a pressure gauge to it to see exactly what it's doing

again any input, tips, advice helps

Thanks
Trevor

Lil Giants
01-22-2012, 02:30 AM
Your pressure relief valve is that black cylindrical hunk of metal that's sitting atop your servos. The end of it facing the rear of the model, there's an allen screw, turn it inward increases your pressure.

The best place to mount your guage is the black line from your pump to your valve, you'll get your most accurate reading there.

Can you shoot some video & put it on youtube? It'd be great to hear & see how this new version works. ;)

tman1986
01-22-2012, 05:20 AM
Hey, thanks for the great input

lol, i feel like i'm going in a bit of a circle but if that is the pressure relief valve then where is the filter? and if there isn't one wheres the best place to get one?and where would be the best place to put it in this system?

also im cuious about the oil cooler that was mentioned earlier, is there any links or anything regarding it i cant really picture what it would look like for an application this small

i will try and work on a video, but i've never posted anything on youtube yet and dont have much to record, i'm in canada and it's frozen solid outside so thats a no go, and i haven't picked up any dirt to play with in the garage yet :(

i can tell you that it will effortlessly lift a tamiya txt-1 monster truck fully loaded (about 12lbs) with the boom at full extension and the bucket flipped to hold the "S" hook with no help or added weight, it could defenitly lift at least double that at full extension but i would have to hold it down, it really surprised me, all at stock pressure/power/control settings

kinda live and learn but i thought this was pretty funny

my friend was sitting with me and he also wanted to see / feel how strong it was so i dropped the bucket down on his knee, he had his hand there cause he was skeptical, i pushed a little he said go more, so i went a little more but at the same time i acidentally made the bucket retract... and it ripped his fingernail off, the teeth are surprisingly sharp, i would not consider this a toy in anyway but a man's toy

anyways as always thanks for all your help / input i really appreciate it

Thanks
Trevor

grumpygrady
01-22-2012, 11:12 AM
maybe i missed it somewhere but what brand and model do you have?

Hey i just got my first excavator and i have a couple question's about the hydraulic system that hopeully someone here will be able to help me out with

1. is it possible to put too much oil in the system, is there suppose to be some air (as cylinder volume isn't the same both ways) in the resevoir, for instance i put oil in with all cylinders while they where compressed, ran it, put more oil in with cylinder extended ran it, but notice drop in power and that my resevoir would actually move from im guessing pressure build up when the cyinders compressed, i allowed a bit of oil to come out the breather and power was increased but im not sure about what im doing here... any tips would be great

in other words how do i know when i have enough oil in my hydrualic system

2.whats the proper way to use the breather on my resevoir i know what it does but what is it's purpose, is it simply for relieving pressure for opening the system, or is it vital in the proper function of the machine while it's running
again any tips would be greatly appreciated

i may have some more Q's in the near future but i figured i would start here as ive read through many many forums and threads but could not find specific answers to these questions

The machine im talking about is the rc4wd earth digger btw i was sceptical about purchasing it cause it's from china i thought the quality wouldn't be up to par with other models but i must say every aspect of this machine greatly exceeded my expectations, i haven't seen much written about it by anyone who bought one here or anywhere for that matter so if anyone has any Q's about it i would be more then happy to answer

just a bit about it,
i was told i got version 1.5 it's valve block is different from most i've seen it's 3 spool but has 4 servos one is switch operated to relieve some pressure in the system along with the main pump switch make's it seem pretty efficient, one way for show and moving the boom around almost zero strain on motor, flip the switch and full power through the pressure valve for digging, i thought that was neat and unexpected, sorry i had to mention it

Thanks for any and all replies
Trevor

tman1986
01-22-2012, 07:19 PM
Hey, lol sorry about that i could've sworn i mentioned it but reading back i obviously haven't, it's the rc4wd earth digger, i just couldn't justify the $4000 price difference for a machine with less power, and i wanted something with replacement parts readily available in the US, so the choice was quite simple for me and i couldn't be happier

any one know a good place to get proper scale vinyl construction equipment decals?

Thanks
Trevor

tman1986
01-26-2012, 10:58 PM
Hey i was just wondering if anyone could shed some light on my question about filters

*Quote*
lol, i feel like i'm going in a bit of a circle but if the black hunk of metal on my servos is the pressure relief valve, then where is the filter? and if there isn't one wheres the best place to get one? and where would be the best place to put it in this system?

There are some pics of my system a couple posts up,
sorry for kinda hovering on this but i really dont wanna run my machine no more if it doesn't have a filter and everywhere else ive looked and asked has just brought me to dead ends

Thanks for any info
Trevor

doodlebug
01-27-2012, 05:32 AM
Put the filter inline between the valve bank return line and the hydraulic tank. Maybe somebody else on the forum can suggest a source for a hydraulic filter.
Cheer's, Neil.

Lil Giants
01-28-2012, 10:03 PM
This style of filter came with my Vario model... don't know where to get one though. It sorta looks like an inline fuel filter... Vario's mainstream hobby models are large rc helicopters, so it could be a fuel filter? :confused: Try looking for one at your LHS.

http://www.vario-earthmovers.com/uploads/tx_templavoila/IMG_2022.JPG

RCLogger
03-15-2012, 01:10 AM
Any updates Trevor ?

greg

doodlebug
03-15-2012, 07:08 AM
I found this link for filter's the other day http://catalog.industrialspec.com/viewitems/filters-plastic-serviceable-cleanable-/ilcf?
10-25 micron should be ok for the model's.
Cheer's, Neil.

FlyingBeagle
03-15-2012, 11:30 AM
It looks a lot like the fuel filter for a lawn mower that you can buy at lowes, I dont know if the filter media is the same, but that is what it looks like.


http://www.lowes.com/pd_336006-63311-531308143_0__?productId=3316796&Ntt=fuel+filter&pl=1&currentURL=%2Fpl__0__s%3FNtt%3Dfuel%2Bfilter&facetInfo=

tman1986
03-18-2012, 02:03 AM
Any updates Trevor ?

greg

Not really much new, haven't got around to getting a filter yet so i haven't been using it as much as i'd like to but the weather is getting nice out so..., but i probably have about 40 to 50 hours on it, theres no leaks, nothing broken or anything, it works like the day i got it maybe even a bit better

And to your pm i'm in ottawa, ontario

part of why theres not much new is i've been doing nothing but work lately saving up for my first mill (really eating in to the playing time) and i know this isn't the correct thread, but is this a good mill

http://www.busybeetools.com/products/MILLING-M%7B47%7DC-MINI-DIGITAL-READOUT-MT3.html

any advice or info would be great
and i'll shoot more out here about the digger once i get some more hours on it

Thanks
Trevor

titandigs
03-18-2012, 08:35 AM
Trevor
For a filter you could try one from Liembach (germany) TTM model shop in Essen Germany sell these items, they are very helpful with information.
Paul

RCLogger
03-18-2012, 08:50 PM
Not really much new, haven't got around to getting a filter yet so i haven't been using it as much as i'd like to but the weather is getting nice out so..., but i probably have about 40 to 50 hours on it, theres no leaks, nothing broken or anything, it works like the day i got it maybe even a bit better

And to your pm i'm in ottawa, ontario

part of why theres not much new is i've been doing nothing but work lately saving up for my first mill (really eating in to the playing time) and i know this isn't the correct thread, but is this a good mill

http://www.busybeetools.com/products/MILLING-M%7B47%7DC-MINI-DIGITAL-READOUT-MT3.html

any advice or info would be great
and i'll shoot more out here about the digger once i get some more hours on it

Thanks
Trevor
I have the same mill Trevor, I use it a lot. I am not a machinist but I am learning more every time I us it.. I am sure it can do more than I will ever be able to do with it...

Greg

titandigs
03-19-2012, 05:35 AM
The breather on the tank should be open 1/2 to one full turn only and this will also help to keep the temp down on the oil. A friend of mine has one of these machines and this helped him.
Paul

Mally Trucker
08-06-2012, 04:42 PM
Hey
just thinking about getting one of these. Did you buy this from Hong Kong or from RC4WD?
So all in all, would you recommend it, once all the niggles are ironed out? :confused:
Thanks
Mally
UK

tman1986
08-09-2012, 02:40 AM
I got mine from RC4WD, it's the version 1.5 one

and all in all i would definitely recommend it, got it about a year ago and haven't had a single problem

it gets about 3 - 4 hours use a week

Trevor