Dake Air Draulic - 906 series - Manual (Page 3)

Model 6-225, 6-425, 6-250, 6-450,
6-275, 6-475, 6-650, & 6-850
3
2. If press will not develop rated tonnage.
a. Dirt under valve balls. Refer to MAINTENANCE 1 – c above.
b. Worn cup leather. Refer to MAINTENANCE 1 – d above.
c. Relief valve not set properly. This valve is located on the top side near the right end of the
control block at the front of the reservoir. The valve is set at the factory to bypass oil from the
pump back to the reservoir when the press reaches its rated capacity. The load on the spring
(Item 91), which governs the pressure at which the valve will bypass oil, is adjusted by turning
the screw (Item 90) in to increase pressure or out to decrease pressure. Replace seal (Item
89) and cap nut (Item 88). NOTE: We advise that the relief valve not be tampered with
after it is once set at the capacity of the press.
3. If nothing happens when press is operated.
a. Release valve open. Be sure to have release valve firmly closed when using press.
b. If the ram will come down only a fraction of its rated stroke, check the oil level in the reservoir
with the ram at the top of its stroke. It should be visible in the sight window at the side of the
reservoir.
4. If press is operating slow.
a. Check air supply line for restrictions to determine if air motors are getting ample supply of air.
b. Release valve not closed properly. Release valve must be firmly closed when using the press.
c. Wrong hydraulic fluid. After considerable research and tests made with the cooperation of the
pump manufacturer, we recommend Mobil DTE 24 oil or equivalent.
5. If Oil is coming out of the air vent.
Drain out the spring chamber by removing the 1/8” pipe plug, which is put in the hub or boss that
contains the oil seal where the ram extends out of the reservoir. Once oil is drained, run the press up
to full tonnage with pipe plug still out. Excessive oil is a sign that the head seal has been damaged.
Refer to Maintenance section 1 item d to replace seal. Replace pipe plug.
6. Excessive leakage around the ram.
Drain out the spring chamber as instructed in Maintenance section 5. A small amount of oil in this
chamber facilitates lubricating the bushing the ram passes thru and prevents scoring. However, if
operation performed on press is spoiled due to slight leakage of oil, remove pipe plug as described in
MAINTENANCE 5 and connect tube line to continually drain this chamber.