Case Drain ?

[DIRTROAD]

What is the best way to plumb a case drain for an attachment?

I will be running the attachment on the excavators thumb circuit. Can I plumb the case drain back into the return line or does it have to go back to the tank seperately?

 

[QwikDraw]

The one I plumbed on the Daewoo goes all the way to the tank.

The reason you need one is the return line cannot take all the oil from the motor without creating too much pressure so the need for another separate line.

 

[Eagleview]

It also needs to be well below the surface of the oil in the tank , I "Tee'd" into an existing fitting on the side of the tank .

 

[fishfactor]

Excavator mulching head in your future?

 

[Robbie Hegwood]

The reason it goes straight to tank is the case cannot see more than 50 psi. Over 50 psi will blow the motor seal. Yes Iron Horse is right, even the tank will build up 10-20 psi. Lastely you need to filter this line. Most systems filter on the return side. The case drain bypasses this line and if something let's go in the motor it can contaminate the system. This is also how we do all of ours.

 

[DIRTROAD]

Thanks for the education on case drains!

Now that I understand the concept better, I know what needs to be done.

Hopefully if all goes well, I will have some pics to post soon. (I don't want to count my chickens before they hatch!)