Valve assembly for machine fluid operations

1. A system, comprising:

a valve assembly, wherein the valve assembly comprises:

a first port;

a second port fluidically couplable with the first port upon application of negative pressure at the first port;

a third port fluidically couplable with the first port upon application of positive pressure at the first port; and

a first check valve positioned between the first port and the second port; and

a second check valve fluidically couplable with the third port upon the application of the positive pressure at the first port, wherein the second check valve is positioned external to the valve assembly.

2. The system of claim 1 , wherein the second check valve is further positioned between the third port and a fluid filter of a machine.

3. The system of claim 2 , wherein the second check valve is further positioned proximate the fluid filter.

4. The system of claim 1 , further comprising a first fluid line fluidically couplable with the valve assembly, wherein the first fluid line comprises:

a first end proximate the second port; and

a second end proximate a fluid reservoir of a machine.

5. The system of claim 1 , further comprising a second fluid line fluidically couplable with the valve assembly, wherein the second fluid line comprises:

a first end proximate the third port; and

a second end proximate the second check valve.

6. The system of claim 1 , wherein the second end of the second fluid line is further proximate a fluid filter of a machine.

7. The system of claim 6 , wherein the second fluid line is fluidically couplable with the fluid filter upon the application of the positive pressure at the first port.

8. The system of claim 1 , further comprising:

a first fluid line fluidically couplable with the second port; and

a second fluid line fluidically couplable with the third port and the second check valve.

9. The system of claim 1 , further comprising a fluid component fluidically couplable with the first port, wherein the fluid component is positioned external to the valve assembly.

10. The system of claim 9 , wherein the fluid component is configured for generating at least one of the following:

the positive pressure at the first port; and

the negative pressure at the first port.

11. The system of claim 1 , further comprising a coupling connected to at least one of the following:

the first port;

the second port; and

the third port.

12. A system, comprising:

a first valve assembly comprising:

a first port;

a second port fluidically couplable with the first port upon application of a first negative pressure at the first port;

a third port fluidically couplable with the first port upon application of a first positive pressure at the first port; and

a first check valve positioned between the first port and the second port;

a second valve assembly comprising:

a fourth port;

a fifth port fluidically couplable with the fourth port upon application of a second negative pressure at the fourth port;

a sixth port fluidically couplable with the fourth port upon application of a second positive pressure at the fourth port; and

a second check valve positioned between the fourth port and the fifth port;

a third check valve fluidically couplable with the third port upon the application of the first positive pressure at the first port, wherein the third check valve is positioned external to the first and second valve assemblies; and

a fourth check valve fluidically couplable with the sixth port upon the application of the positive pressure at the fourth port, wherein the fourth check valve is positioned external to the first and second valve assemblies.

13. The system of claim 12 , wherein at least one of the following:

the third check valve is further positioned between the third port and a first fluid filter of a machine; and

the fourth check valve is further positioned between the sixth port and a second fluid filter of the machine.

14. The system of claim 13 , wherein at least one of the following:

the third check valve is further positioned proximate the first fluid filter; and

the fourth check valve is further positioned proximate the second fluid filter.

15. The system of claim 12 , further comprising at least one of the following:

a first fluid line fluidically couplable with the first valve assembly, wherein the first fluid line comprises a first end proximate the second port and a second end proximate a fluid reservoir of a machine; and

a second fluid line fluidically couplable with the first valve assembly, wherein the second fluid line comprises a first end proximate the third port and a second end proximate the third check valve.

16. The system of claim 15 , further comprising at least one of the following:

a third fluid line fluidically couplable with the second valve assembly, wherein the third fluid line comprises a first end proximate the fifth port and a second end proximate a second fluid reservoir of the machine; and

a fourth fluid line fluidically couplable with the second valve assembly, wherein the fourth fluid line comprises a first end proximate the sixth port and a second end proximate the fourth check valve.

17. The system of claim 12 , further comprising a fluid component fluidically couplable with at least one of the following:

the first port; and

the third port, wherein the fluid component is external to the first and second valve assemblies.

18. The system of claim 17 , wherein the fluid component is configured for generating at least one of the following:

the first negative pressure at the first port;

the first positive pressure at the first port;

the second negative pressure at the fourth port; and

the second positive pressure at the fourth port.

19. The fluid system of claim 12 , further comprising a coupling connected to at least one of the following:

the first port;

the second port;

the third port;

the fourth port;

the fifth port; and

the sixth port.

20. A system, comprising:

a check valve fluidically coupled with and positioned proximate a fluid system of a machine; and

a valve assembly fluidically coupled with the check valve, wherein the valve assembly is external to the check valve and comprises means for performing:

a fluid evacuation operation on the machine upon application of negative pressure to the valve assembly; and

a fluid refill operation on the machine upon application of a positive pressure to the valve assembly.