Murzan DUS-Reassembly through Dry Test

Murzan DUS-Reassembly through Dry Test
Murzan DUS-Reassembly through Dry Test


Prior to reassembly, ensure that the machine carriage is fully lowered and is not raised on the mobile casters.

Begin by reattaching the diaphragm assemblies to the pump. Start by sliding the side that has the shaft attached through the middle of the pump. It may be beneficial to FOLD the diaphragms outwards for this step.

Next, attach the opposite side diaphragm assembly to the open end of the shaft. Ensure that the washer aligns with the shaft as the assembly is threaded on. Thread the assembly on until hand tight.

Next, take two ¾” wrenches and tighten the diaphragm assembly further. The wrenches should be placed on the outer pistons and rotated clockwise.

Next, reattach both product chambers to the machine. To do this, start by folding one diaphragm so that the rubber bead is flush with the air chamber. Next, press the product chamber against the outside of the diaphragm ensuring that the product chamber also lines up with the diaphragm bead. Using a level, check that the top ferrule of the product chamber is level with the ground before proceeding. The product chamber can be rotated radially if the ferrule is not immediately level.

Once the product chamber is level, reattach the product chamber clamp to the top half of the product chamber using a mallet. The product chamber, diaphragm, and air chamber should hold together once the top half is on. Apply the bottom half of the clamp also using a mallet. Confirm product chamber level one final time before tightening the clamp.

Using a prybar, move the diaphragm assembly to the other side of the pump. Be sure that the prybar contacts the aluminum inner piston – NOT the diaphragm itself. It may be helpful to remove the air inlet connections if you find it difficult to cycle the pump to the other side.

Next, fold the diaphragm so that it aligns with the air chamber. Reattach the product chamber and product chamber clamp using the same method as above and ensuring that the product chamber is level. Note; sometimes the diaphragm assembly will not stay still at the second side. Use another person to hold the diaphragm still from the opposite side in this scenario.

Next, connect the machine to air and test the pump. Murzan recommends running the pump dry for at least 1 minute to check for leaks. It is better to find a leak now than to find one once the whole machine is reassembled.

Once the dry run is done, it is time to reattach the follower plate. Raise the carriage to the top and roll in the cart with the follower plate. Note; ensure the vacuum break hole on the plate is in the right spot.

Next, carefully lower the machine onto the follower plate, ensuring that the two studs for the wing nuts line up. It may be beneficial to slightly wiggle the cart so that the holes line up.

Loosely attach the two wing nuts so that the follower plate is now reattached to the machine, but still has some play.

Raise the machine slightly so that the follower plate can be moved freely. Align the bottom check valve ferrule with the product chambers and attach on both sides. It can be helpful to slowly tighten the wing nuts to raise the plate as the clamps are aligned.

Next, tighten the wing nuts all the way and reattach the vacuum break clamp. Ensure that the vacuum break check valve is in the right orientation – pin facing UP.

Next, raise the machine to the top and remove the follower plate cart. Lower the machine to the bottom once the cart is removed.

Next, attach the discharge check valves to the top of the product chambers. Ensure that the check valves have a check ball and ball stop before proceeding further. Note; Murzan recommends leaving all clamps loosely attached to allow for easier assembly. The clamps can be tightened at the end once every component is reconnected.

Next, insert the PIG launcher and tighten the support bracket clamp with the PIG launcher as high as possible. This will give you space to install the discharge Y and then lower the PIG launcher onto it.

Next, it is time to reattach the discharge Y. Murzan recommends assembling the 45 degree pieces and Y piece on a level surface prior to reattaching to the machine. Start by placing the Y on the two 45 degree pieces that are seated on a level surface. Check the level of the top ferrule of the Y and confirm that it is level in both directions. Adjust the alignment if the top ferrule is not level. Clamp the top of the 45 degree elbows to the bottom of the Y once everything is level.

Next, place the Y assembly to the top of the discharge check valves.

Next, attach the short discharge spool to the top of the “Y”

Next, lower the PIG launcher onto the spool above the Y and attach. Lower by loosening the bracket’s clamp.

Next, attach 90 degree elbow to the top of the P.I.G. launcher

Next, attach the horizontal spool to the open end of the 90 degree elbow. Ensure that the white plastic support aligns with the support bracket. Tighten the support bracket clamp after the horizontal spool has been fastened to the elbow.

Next, reattach the second 90 degree elbow to the horizontal spool. It is critical that this elbow’s clamp is left loose to allow for play when reconnecting the hose.

Finally, reattach the 4” discharge hose to the open end of the elbow and counterbalance. Murzan recommends using two people for this task.

Next, go back through the machine and tighten every clamp. Inspect each clamp as they are tightened to ensure that the gaskets did not misalign during the reassembly process.

Finally, test the machine dry before placing back into operation. Murzan recommends testing each function to check for air leaks. Tip; placing your hands over the mufflers can help confirm the pump is cycling correctly in loud areas.


Published: January 3, 2024