Uwatec MK 25 Assembly instructions

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

SCUBAPRO

Repair Guide

MK 25/MK 20

First Stages

USE THIS GUIDE AS A REFERENCE WHEN SERVICING

THE MK 25 AND MK 20 FIRST STAGES

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

TOOLS NEEDED FOR REPAIR OF MK 25-MK 20

P/N43040000

TOOLS

NEEDED

Quantity Part Number Description

1 Ratchet

1 20-155-500

(Peter Built)

1” Yoke Nut Socket

1 20.150-200

(Peter Built)

MK 25/MK 20 Assembly Tool

1 set 10.102.100

(Peter Built)

Brass o’ring picks

1 tube 41.047.000 Christo-Lube Christo-Lube

OXYGEN COMPATIBLE LUBRICANT

P/N 41-047-000

1 47.010.000 Counter Mat

1 41.496.101 Lubricant syringe Monoject

1 43.040.000 Universal Tool

1 20-115-100

(Peter Built)

First Stage Handle

1 Torque Wrench

1 Hex Key Set

1 Crescent wrench

1 20.500.200

(Peter Built)

Pneumatic Adjusting tool

1 18.300.500

(Peter Built)

Blow Gun/Air Nozzle

ICON LEGEND

Inspect carefully, replace if needed

Monoject Lubricate properly

Replace annually

Dynamic o’ring, lubricate properly

P/N43040000

TOOLS

NEEDED

No tools needed for this step

Indicates the regulators affected by this step

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

Remove all hoses.

Thread the first stage handle into the

high-pressure port as shown.

Use the ratchet and yoke nut socket to

remove the yoke nut from the first

stage.

Remove the yoke cover if cleaning the

yoke is indicated.

5/32”

For DIN Regulators

Remove all hoses.

Thread the first stage handle into the

high-pressure port as shown.

Loosen the filter retainer using a 5/32”

hex wrench.

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

Remove the yoke nut and cap from the

first stage.

Loosen the star clip and remove the

filter.

Remove the yoke nut o’ring.

6mm

For DIN Regulators

Remove the filter retainer, spring, filter,

DIN adapter and o’ring.

Loosen the DIN fitting using a 6mm hex

wrench.

Remove the end cap.

Loosen the seat retainer using a

properly sized wrench while holding the

first stage with a first stage handle.

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

3/8”

On some early models of the MK 20

this was loosened using a 3/8” hex

wrench.

Loosen the seat retainer while holding

the first stage with a first stage handle.

5/32”

Remove the seat retainer. The high-

pressure seat assembly and spring can

now be removed.

On the current version of the MK 25 the

seat retainer is adjustable.

Disassemble for cleaning using a 5/32”

hex wrench.

NOTE: The adjusting screw is turned

clockwise to remove.

Use the universal tool to loosen the cap

from the body. Hold the regulator body

with a first stage handle.

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

P/N43040000

TOOLS

NEEDED

No tools needed

this step

Separate the cap from the regulator

body. Carefully remove the piston

assembly and spring.

Use the brass pick (blunt end) to

carefully push the piston stem o’ring

assembly from the regulator body.

7/32”

5/32”

Use a 7/32” hex wrench to remove the

swivel retainer from the regulator cap.

Use a 5/32” hex wrench to remove the

low-pressure plugs.

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

Monoject

7/32”

Following cleaning, inspect and

lubricate o’rings and washer as shown.

Reassemble the swivel retainer to the

regulator cap using a 7/32” hex and

torque wrench. Apply 70 in-lbs/8 N-m.

Monoject

Insert the stem o’ring assembly using

the stem o’ring insertion tool. The

o’ring should be lubricated to dynamic

specifications.

Note that the washer with the ledge

should be placed as shown during

reassembly.

Push the assembly into the regulator

body.

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

Remove the insertion tool by twisting

slightly and then pulling out, then

reverse the tool and re-insert it into the

regulator body.

Reassemble the piston assembly.

Replace and lubricate the piston

o’rings.

Hold the o’ring insertion tool in place to

insure that the piston knife-edge is not

damaged during assembly.

Thread the cap and swivel assembly

on the regulator body. Hold the o’ring

insertion tool in place to insure that the

piston knife-edge is not damaged

during assembly.

Tighten the regulator body to the cap

and swivel assembly using the first

stage handle and the universal tool as

shown.

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

Monoject

5/32”

Replace the high-pressure seat and

replace/lubricate the high-pressure

o’ring. With the spring and the spacer,

Insert in the regulator body.

In the MK 25 the adjusting screw

should be re-inserted into the high-

pressure seat retainer using a 5/32”

hex wrench.

NOTE: To tighten the adjustment

screw, turn counter-clockwise.

Tighten the high-pressure seat retainer.

Use a torque wrench to tighten to 130

in-lbs/15 N-m.

3/8”

On some early models of the MK 20

the seat retainer is tightened using a

3/8” hex wrench.

Tighten the high-pressure seat retainer.

Use a torque wrench to tighten to 130

in-lbs/15 N-m.

SCUBAPRO MK 25/MK 20 First Stages

2003 SCUBAPRO

Important note: The following information is not designed to be a complete training guide for servicing the listed SCUBAPRO regulators. All SCUBAPRO

technicians are required to attend an annual service training program to insure safe handling and servicing of SCUBAPRO products. All SCUBAPRO technicians

must be employed by an authorized SCUBAPRO facility.

Monoject

Replace the filter and star retainer.

Lubricate the yoke nut o’ring.

Insert the filter, o’ring, and star retainer

into the yoke nut. Assemble with the

yoke saddle.

Monoject

For DIN Regulators

Lubricate the DIN fitting-to-body o’ring.

Assemble the o’ring and DIN fitting to

the regulator body.