Chinese Mini Excavator: Cushion Valve (aka Dual Acting Relief Valve) Hydraulics Explanation

[@richieapalmer]

Because of people like you these machines will/can become absolute tanks and bulletproof. Keep it up brother you deserve it......

[@thegarageconnection]

Thanks a ton

[@richieapalmer]

Will you be selling the hydraulic filter kit for the QH12 soon because I really need one? I check your website everyday hoping to get one before they sell out.

[@thegarageconnection]

@@richieapalmer I’ll set one aside for you I’m 95% done with them

[@garymoore3399]

Sounds like something that I would be interested in for my machine. I will be watching for the installation and pricing. Keep up the good work.

[@jdimeo1966]

Ditto

[@rjks1031]

You are an absolute gift to the mini digger community, because of you many issues will be solved. Keep up the great work 👌👌

[@NoThemeMischief]

These videos are awesome and well done. These minis are a niche market for sure. I didnt think too hard about the slew of the machine but I did consider that sproket a weak point.

[@kevincrawford2027]

Great explanations I have learned a lot from your videos. Looking forward to how set the pressure on the cushion valve.

[@repaircollc]

I dont own any of these but I'm sure I'll come across one soon enough. You have a great way of explaining things. It's nice to hear someone knowledgeable on here. Can't wait for more.

[@jdimeo1966]

Thanks! Looking forward to the follow up video on this.

[@thegarageconnection]

Coming soon!

[@juice0366]

If there is a kit with all parts I’d like it!

[@donaldstrishock3923]

This is some Great "RE-Enginering". Thank you Sir for the "Enlightenment". Best wishes with all your endeavours.

[@jeremyc9229]

I am a guy who learns the machine as it is. That said, running this machine compared to my good stuff, sometimes weighing in more than 20 or 30,times the weight of this, This machine is twitchy as hell! I can learn it as is, but, I don’t want it to effect what I know. Thanks!

[@OrganicVeggieLoaf]

Great video, thanks for posting! My AGT mini has a jerky boom and it goes way too fast to be practical for me. Can I just install a flow restriction valve on it instead of a cushion/relief valve?

[@jjuggernaut3218]

Is the kit out yet??? I’m one of those guys on the Facebook groups!

[@jimhawes9414]

Cushion valve got me thinking about an annoying issue with my boom cylinder. I have a 2t , reasonably higher end 19h0 Chinese Ex. Cylinder mount on top side, so more down force than lift. When I go gently in the lift or up direction and close the valve many times the cylinder will violently pogo stick until the boom retracts to the ground will the control is centred. A video on this would be a real good idea, I think metering the cylinder may cure this. Or may may I should turn the cylinder around for lift power and reduce the downforce. The pump puts out 15 g/m. The machine is new. Really enjoy your content.

[@Jrboon4579]

Thank you I definitely have learned from this video this will have to be a must. I also would like to know more about the variable hydraulic valves that you sell and how to install

[@raydoyle2020]

Do I need a cushion valve on a 3 1/2 ton Chinese mini excavator as well?

[@tippietop4844]

After adding cushion valve and new lines, how to ensure no air in the system?

[@larrybester3420]

What do you think about adding a small hydraulic accumulator into the pressure side of the hydraulic spool manifold to reduce jerkiness ?

[@malcomthuresson9692]

I really appreciate those videos, Looking forward to see if you are able to make any upgrades on the somewhat cheap DCV. I have almost the same machine myself and really need some upgrade for the boom arm which is really jerky. I have some ideas for servo joystick controls with rc servos but have some concerns with safety for that idea. Another is to add pilot control joystick to get some better comfort when digging multiple hours a day. looking forward to see your thoughts and ideas. Keep up the work!

[@RunsWithScissors]

another great video, thanks for posting it.

[@smca7271]

Dingo has a similar system,they have counter balance valves,with a variable throttle between A and B.The throttle cushions the stop,and the counter balance slows the overrun (like going downhill).looks a great idea.

[@jimmy.t5850]

If one line is redirected back into the feed line . Wouldnt that cause the slew motor to keep rotating while the control valve is blocked off ?

[@thegarageconnection]

Only if the pressure exerted on the cushion valve exceeds the lifting pressure of the relief valves

[@rodneyball6017]

Great video ran equipment for 30 plus years never knew that about hydraulics watched many of your videos about the Chinese minis learned plenty getting ready to buy one witch one is the best price e.g. cheapest lol

[@semo-dyer5183]

Hi Ken, I find the drive motors to be the hardest thing to deal with on mine. Have you put any thought into smoothing out those controls?

[@terrylutke]

Wouldn't 2 small hydro accumulators do the same thing? If so, they would effectively 'lock' the swing once they recharged. Also an accumulator probably wouldn't require a dedicated blow-down/discharge line.

[@terrylutke]

Actually I should've looked at accumulator prices before commenting, Yikes!

[@maximus297759]

Thx man I can be a lot more gentle with this now understand what can happen.

[@davidolson6832]

Hey there! I just bought two SCL 850 mini skids from an auction There is like absolutely no hydraulic pressure whatsoever, and I looked at the relief valve and noticed there was no bolt holding it down. By chance do you know the size of the bolt? I bet they might be pretty generic between all the machines

[@OneLex-e1o]

I ordered mine with pilot valves, I assume I won't have this problem? (Hasn't arrived as yet)

[@JohnEllis-u1u]

Hi cam I’m hearing that these mini’s free wheel down hill . Would love to see a safety video on these . Might save a life . Thank you

[@TheKallipugos]

Do you have a recommendation for thread sealant on hydraulic fittings?

[@thegarageconnection]

I use a product called true blue but any Teflon based product should work just fine for tapered thread only. Any thread with a metal to metal mating surface or an O-ring should be dry.

[@stallion1983]

Is there a chance that this has been developed? I would like to see this for all controls. Thanks

[@thegarageconnection]

There are kits available on the central digger supply website called cushion valve kits

[@gbckpb]

Hey there good afternoon. Really appreciate your helpful videos, had a question about tracking down hill. Was hoping you could answer? Have new agt L12 actually comes factory with oil cooler already with fan switch but no filter? Any way, when I’m tracking down a small downhill the motor or pump kinda chugs? Like maybe machine is starting to go to fast for system. Kinda lags out.. but when your on flat ground tracking controls and everything is normal. But second your on a decline tracking kinda here system stall out then come back and repeat. Is this normal?

[@1966thewoodsplitter]

The drive motors definitely need something to smooth them up.

[@teslabogger]

I see some people are using this cushion valve dcrv45-06n, I would be interested in a kit if you decide to sell one.

[@thegarageconnection]

Kits are available at the centraldiggetsupply website

[@jaredthompson1522]

I got a rippa 1ton. Trying to reduce the jerkiness of the up and down boom. Would this concept fix this issue for me?

[@thegarageconnection]

A flow restriction valve would

[@jaredthompson1522]

@@thegarageconnection is there a particular website I could find that at for these minis?

[@jaredthompson1522]

@@thegarageconnection is that also considered a flow control valve?

[@RunkStillRides]

Mine will freewheel if controls are held at a certain position 😂 found out the hard way down my steep driveway.

[@CGreciful]

Just sell things and I’ll buy them. I love safely tinkering with my machine and want it to last.

[@luisjordan4162]

Promo SM

[@chrisbryden8102]

My god these things are twitchy. Maybe you wouldn’t know if you didn’t come from large excavator use. Some decent engineering se the factory could have made them so much better at very little extra cost.