Navajo 4WD V6-4.0L OHV (1991)
Brown or Black
80~F (27~C)
95~F (35~C)
Green or Blue
103~F (39~C)
128~F (53~C)
Yellow
135~F (57~C)
160~F (71~C)
Natural
70~F (21~C)
85~F (29~C)
Gray
125~F (52~C)
150~F (66~C)
3-Port Vacuum Check
Testing 3-Port Regulator Valves
1.
With cold engine, vacuum applied to Port A (center port) should leak from Port C (upper port).
Vacuum should NOT leak from Port B, if Port C is plugged with finger.
2.
With warm engine, vacuum applied to Port A (center port) should leak from Port B (lower port).
Vacuum should NOT leak from Port C, if Port B is plugged with finger.
3-Port Electrical/Vacuum Check
Electrical Vacuum Control Valve Switch
1.
With cold engine, vacuum applied to Port A (center port) should leak from Port C (upper port).
Vacuum should NOT leak from Port B, if Port C is plugged with finger.
2.
Measure the resistance between the the electrical terminals.
3.
With warm engine, vacuum applied to Port A (center port) should leak from Port B (lower port).
Vacuum should NOT leak from Port C, if Port B is plugged with finger.
4.
Measure the resistance between the the electrical terminals.
NOTE: The 3-Port Electrical Vacuum Switch could be opened or closed on a cold engine. After the engine warms up to operating temperature,
the valve will be in the reversed position (closed or opened).
Vacuum Delay Valves