The Monolithic EHP 2000--Peristaltic Carrousel Pump

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Start up Instructions

The Monolithic EHP 2000 is designed for use with small aggregate mortars, pastes, heavy bodied paints, mud, and other thick viscous materials. It works as an excellent small line shotcrete pump for stuccos and concrete. It is made from the toughest materials available at an affordable price. The unit is designed for maximum capacity and minimum maintenance.

EHP 2000 Electric Hydraulic Pump

  1. The electric motor drives a hydraulic pump which in turn drives a hydraulic motor. The hydraulic motor drives the carrousel to get the pumping action.
  2. This pump has a directional hydraulic valve that will allow the carrousel to turn either direction. Push IN and go forward. CENTER is neutral. OUT is reverse. The reverse is on a spring-load and will not lock in.
  3. There is a needle valve adjustment on the flow of hydraulic oil for speed control of the pump.
  4. To remove or rotate pumping line, remove clamps on lower end of line on peristaltic hose. Remove peristaltic hose from lower metal fitting with pump in forward hose can be removed.

To Install Peristaltic Hose Again

  1. Lubricate the outside of the elbow end at the bottom of the hopper and the inside of the hose with pump line lubricant or a heavy soap solution. The wetness and slipperiness will help to force the rubber pumping line over the tube.
  2. Lubricate the internal pump line and feed it into the carrousel by slowly reversing the pump. The pumping action in reverse should draw the pump line into and around the carrousel to the hose connection at the hopper bottom elbow.
  3. After the pumping line has been slipped over the tube at the elbow, attach the hose clamp. The pumping line has a soft internal line and because of this softness, it is virtually impossible to keep the hose from separating unless the hose clamp and the hopper are connected by an external bolt-on strap.


Should the material line become disconnected from the bottom of the hopper, the bolt-on clamp will prevent the metal clamp from being pulled into the pump. Failure to attach the bolt-on clamp will result in damage to the pump and to the squeeze rollers.


Coating the outside of the pumping line with lubricant will greatly speed the installation of the pumping line into the carrousel. The lubricant will also greatly reduce the wear and tear on the exterior of the pumping line. Lubricant can be applied to the pumping line after assembly. Lubricant should be applied at least once a week.

  1. Rotating the pump line regularly will greatly increase the working life. Rotate it once a day or after each 10 yards of concrete is pumped.
  2. The material line can now be attached to the pumping line.
    1. The internal tube with the male quick coupling
    2. The exterior U-clamp
    3. The connecting strap between the clamp and coupling
The external hose clamp and joining metal strap must be used to prevent the pumping line and the material line from separating.

Operating Instructions for Shotcreting

Before starting pump (do not connect material line to the spray gun):

  1. Pour water into the hopper. Turn on the unit by moving the hydraulic valve control lever to the forward position. After the water is pumped from the hopper, add mixed material to the hopper. Pump material through the material line until a uniform consistency of material is flowing. The air line should be attached to the spray gun. A small amount of air should always be bleeding through the spray gun air jets to keep the material from backing up in the air jets.
  2. The material is now being pumped into the material line pushing the lubricating water if front. At the point where the mixed material comes in contact with the lubricating water, there will be some material separation. Should a line pack occur, reverse pump to reduce pressure. The line pack will be where the hose is still hard. Insert a metal rod or a small water line to break up the pack. It is advisable not to put the spray gun on the material line until properly mixed material is extruded from the material line.
  3. The operator stops the pump, washes the end of the material line and attaches spray gun.
  4. Hold spraying air supply and start pump. You are now spray applying material. Move the spray in the uniform circular manner to achieve a consistent thickness of application.
  5. When the spray man wishes to stop spraying, he should anticipate and stop the pump. Material will continue to spray for approximately fifteen seconds, as the pressure of the material in the material line dissipates. If the spray man is using the Monolithic spray gun, he will be unable to completely stop the dribbling of material to the spray gun, and should position the spray gun in a manner that it will not spray an undesirable area. Reducing the air supply to the spray gun to a minimum will allow the excess material to dribble from the end of the spray gun. The slight flow of air to the spray gun will keep material from entering and plugging the air jets.
  6. To clean — Wash hopper and spray gun thoroughly. The material line can be cleaned by pumping sponges and clean water through the pump and the material line. Sponges should be approximately 3" cube (2" cube for 1500), and can be easily cut from a cellulose sponge.

Controlling Speed of Application

The speed of the carrousel pump is controlled by the hydraulic needle valve located in tubing line by hydraulic pump. At maximum flow, the free flow rate is approximately six gallons per minute and will achieve an application rate in excess of 6 plus cubic yards per hour.

Trouble Shooting Problems

Most of the problems encountered will be in the mix of the material.

  1. Improper mixing can cause lumping, resulting in plugging at the material hopper. These plugs are easily and quickly remove by momentarily reversing the pump. The pump will now pump material backwards and the operator will be able to remove the lumps from the bottom of the hopper. Use reverse only momentarily as continued reverse operation will pull the coupling back into the pump causing damage.
  2. Material lumps can be caused by exposure to moisture during storage. Over-aged material will generally result in a lump at the filling spout of the bag.
  3. The unique design of the carrousel pump and material line fittings will pass any smaller lumps directly to the spray gun. Most lumps will pass and be sprayed on the wall.


Do not operate the carrousel pump in reverse while unattended. Explanation: The pumping line will double up inside of the pump and cause damage and/or the coupling between the material in and the pumping line will be pulled into the pump and cause immediate damage.

After the carrousel pump has been completely cleaned, apply oil on the outside of the pump

with a sprayer or a saturated rag. This prevents cement from bonding to the surface of the pump.

CAUTION: Only use the Monolithic Internal pump line! This hose is manufactured specially to Monolithic specifications (Rubber Durometer & Dimensions). Failure will occur with any other product and warranty will be nullified.

Instructions for Removing Internal Carrousel Housing

  1. Remove internal pumping line.
  2. To remove hydraulic motor first remove drive chain, then sprocket, then the motor is ready to be removed. Tools required would be 3/32 inch Allen wrench for the sprocket and a ¾ inch end wrench for the motor.
  3. To remove the carrousel (squeeze roller assembly) you remove the lock collar on each side bearing with a 3/16 inch Allen wrench, then using a punch and hammer rotate the collar until it is loose. Next go inside of the pump and loosen set screws on center shaft. Now the 1¼ inch shaft is ready to be removed. Be cautious not to damage the end of the shaft with the hammer. Now that the shaft is out, the carrousel is ready to be removed.
  4. To remove press rollers, remove two 3/8 inch bolts on the base of each roller assembly, pull roller and holder from frame. A 9/16 inch wrench is required for this job.

To reassemble just go in reverse order.

Recommended Tools

Ratchet Handle 3/8" Drive Small Screw Driver
6" Extension 3/8" Drive Large Screw Driver
1/2" Deep Socket 3/8" Drive Friction Tape
9/16" Deep Socket 3/8" Drive Sponges and Scrubbers
1/2" Combination Wrench 9/16" Combination Wrench
1/8" Allen Wrench 3/32" Allen Wrench
3/16" Allen Wrench  

Last updated October 29, 2001

Click Here! to order the Monolithic EHP2000 shotcrete pump!


177 Dome Park Place - Italy, TX 76651
Tel (972)483-7423 - Fax (972)483-6662
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