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MDE-4334C Atlas Start-up and Service Manual · April 2008
Hydraulic/Mechanical Components
Pumping Unit
3
Carefully pull out the strainer. Keep the strainer in a horizontal position to avoid
contaminating the pumping unit with strainer debris. It may be necessary to use a small tool to
gently hook the inside of the metal strainer end cap.
4
If the pumping unit contains an inlet check valve assembly, remove the inlet check valve.
Inspect the area for cracked or otherwise damaged gaskets. Replace any worn or damaged
gaskets.
5
Remove the strainer from the bore located behind the check valve assembly. Inspect the
strainer for damage. Clean and/or replace the strainer if necessary.
Installing the Strainer Check Valve
To install the strainer check valve, proceed as follows:
1
If the unit is equipped with the check valve option, insert the dome strainer into the bore.
2
Clean any debris from the check valve and carefully inspect the gaskets.
3
Insert the check valve assembly or strainer support into the corresponding pumping unit bore
(see
on
).
Press the assembly squarely over the receiving cylindrical
surface until the gasket seats over the surface and holds the assembly in position.
4
Insert a new or cleaned strainer into the bore, over the check valve assembly.
5
Clean any debris from the strainer cover and install a new gasket.
6
Install the strainer cover. Hand-tighten and keep the cover parallel to the casing face. Torque
the screws to 150 lbs-in (17 Nm). Do not overtighten as it may cause damage.
7
Replace the plug in the hole of the strainer cover.
Note: Use a UL-approved sealant suitable for the fuel involved.
Service Tips
• Clogged strainers should be frequently cleaned using denatured alcohol. If damaged or
permanently clogged, replace the strainer.
• If check valves are sticking, it may cause reduced flow rate. If stuck open, check valves
cause the loss of unit prime.
• It is a good service practice to replace the strainer cover gasket when servicing the strainer
or check valve. This will help avoid subsequent leaks.