2 way aux hydraulics on Cat 420D what is needed?

[SHRC]

I have a 2004 cat 420D that came with auxiliary hydraulics on the boom. It also came with a small foot pedal (push switch) with a 2 prong plug in. The previous owner was using it to run a breaker.

The question is, it currently only has one way hydraulic flow, what will I need to purchase to run 2 way flow for a grapple or auger?

Thanks guys!

 

[Nige]

Please post a Serial Number. It helps to find info on how your machine was originally configured.

 

[SHRC]

That’s a good idea, thanks Nige,
Ser # CAT0420DPFDP25682

 

[Nige]

You may be surprised to find that your machine was actually built in August 2005.

The Aux has been added since it was originally built. Your machine should be equipped with a 5-section main control valve as shown on the left. The usual AUX installation uses a 6-section control valve with the 6th section (arrowed) controlled by a lever running the AUX function.

So it appears what you have on the machine right now is a lash-up. Maybe someone else can give you some guidance.

 

[SHRC]

Yes, that is correct it is an 05. That doesn’t sound like good news…. It appears to have the t section main control valve.

If it was an after market installation for the aux lines on the boom, I wonder where the valve for it is? Would it just be a one way valve?

Here is a picture of the foot control