Hellenbrand Iron Curtain System Compressor Service KIT Rebuild Kit, Part # 74-650571, 74-650465. Water Treatment Iron Curtain Parts.

Listing is for a brand-new Rebuild Kit.  This kit once installed will restore working pressures / vacuum specifications to your pump.   Listing is for 1 -rebuild kit only.  NO other parts or accessories are included.  DOES NOT include the Compressor.

FITS ALL 405 Iron Curtain Pumps as pictured.

Original Specs / Product Details

Piston Air Compressor, 1/10 HP, Voltage 12VDCFull Load Amps 10.5, Inlet Size 1/8 In. NPT, Outlet Size 1/4 In. NPT, Max. PSI Cont./Int. 100/100, Free Air CFM @ 50 PSI 0.41Overall Length 7-1/2 In., Overall Width 4-1/4 In., Overall Height 5-1/3 In., Cylinder Material Aluminum, Number of Cylinders 1, Motor Type Permanent Magnet, 3450 RPM, 63 dBA @ 60 psi Sound Rating Lubrication Type Oil-Less, Finish Gray, Valve Corrosion Resistant Sandwich

 NOTE: Before you begin, read the instructions thoroughly and assemble the necessary tools.

 You will need:   Torx T-25 attachment for torque wrench (for head screws).

 5/16” allen wrench for for torque wrench (eccentric screw) 

 Flat Screwdriver 

DISASSEMBLY

STEP 1. Clean loose dirt from the outside 

of the compressor.

STEP 2. Loosen the 4 head screws (1) 

and remove the compressor head (2). 

STEP 3. Carefully remove the valve plate 

(4) from the bottom of the head.

STEP 4. Remove the head gasket O-ring

(3) and discard. Turn the valve plate over.

Remove the cylinder sleeve O-ring and

discard.

STEP 5. Remove the slotted screw on 

the top of the valve plate and discard. 

Remove the valve keeper, valve flapper, 

and o-ring and discard.

2 3

STEP 6. Remove the 4 screws (A) securing the front cover (Figure 2). Remove the 

front cover (B) and discard old front cover 

gasket (C).

STEP 7. Remove the plastic ratchet (D) 

securing the foam filter (E). Remove filter 

and discard. Set the ratchet aside for assembly later.

STEP 8. Rotate the eccentric bearing 

assembly so that the hex head of the set 

screw is facing the side of the housing 

you just removed the filter from. Place 

the 5/16” allen wrench in the vent hole 

and loosen the set screw and slide the 

Connecting Rod Assembly off of the shaft. 

Remove it through the top of the housing 

and discard.

REASSEMBLY

STEP 9. Clean the top of the valve plate with a 

clean, soft cloth. Install the new o-ring, exhaust 

valve flapper, and restraint. The valve keeper 

should be placed on top of the flapper so that 

the word “UP” is visible. 

NOTE: Torque flapper screw to 18 inch pounds.

STEP 10. Install the new head gasket, seating 

it firmly into the groove with your finger or blunt 

object. (See Fig. #3). Set aside.

STEP 11. Insert new rod assembly through top 

of housing (same as removal). Align set screw 

on eccentric bearing with the flat of the shaft (eccentric toward housing). Push assembly onto the 

shaft until the eccentric touches the housing. 

STEP 12. Temporarily place the valve plate assembly on the compressor housing so the lip of 

the cylinder sleeve fits into the O-ring on the 

bottom of the valve plate assembly. Position the 

valve plate so the mounting holes line up with 

the threaded holes in the housing. Temporarily 

insert two head screws into the mounting holes 

to secure the valve plate assembly.

NOTE: The purpose of this procedure is to correctly position the connecting rod assembly on the 

the motor shaft before tightening the set screw.

STEP 13. Use a torque wrench to tighten the eccentric set screw to 55 inch-pounds. Remove the 

valve plate assembly and head screws.

Figure 3

CHECK OPERATION: Hold the sleeve down against the housing with one hand, and 

slowly rotate the motor shaft with the other hand to ensure all components are lined up 

properly. As the piston travels up and down it will also rock from side to side. This is a 

feature of the WOB-L Piston. If the piston rocks from the back to the front, re-align 

the eccentric bearing on the shaft.

STEP 14. Place the head gasket into the groove located on the bottom on the head. Place 

head on flat surface upside down.

STEP 15. Place the valve plate on the bottom of the head with exhaust valve flapper 

down. Place o-ring into groove on bottom of valve plate.

STEP 16. Turn head and valve plate assembly right side up and place on top of housing 

locating the o-ring onto the top of the cylinder sleeve. Tighten the 4 head screws to 40 

inch-pounds.