Thomas Sk2807/72 User manual

MODEL SK2807/72

COMPRESSOR SERVICE KIT

For use on 2807 Compressor Series

CAUTION: Improper assembly or use of damaged parts may lead

to premature failure. To avoid frequent repairs follow the recom-

mended assembly procedures.

Part No.642688 03/05

NOTE: Before you begin, read these instructions thoroughly and

assemble the necessary tools. You will need:

●Phillips head screwdriver attachment for torque wrench

●Flat blade screwdriver attachment for torque wrench

●Torx T-20 attachment for torque wrench

●Torx T-25 attachment for torque wrench (for head screws).

●5/32” allen wrench for eccentric set screw

●Clean Cloths

WARNING: Unplug the compressor before beginning disassembly.

This kit includes 2 sets of the following parts: To avoid confusion,

service only one side of the compressor at a time.

617124 Valve Restraint (2)

617135 Valve Keeper Strip (1)

3524 Washington Avenue

Sheboygan, Wisconsin 53081 USA

(920) 457-4831 www.gd-thomas.com

638415 Dust Shield

625446 Screw (6)

666888 Connecting

Rod Assembly

625646 Head Screw (6)

638760 Head Gasket

656708 Valve Flapper (4)

Exhaust

623638 O-Ring

641010 Filter

656887 Valve Flapper (1)

Intake

623122 Quad Ring (4)

DISASSEMBLY

STEP 1. Clean loose dirt from the outside

of the compressor. Loosen the 6 head

screws and remove the head. (Fig. #1)

Lift off the valve plate.

STEP 2. Remove the head gasket O-

ring and discard. Turn the valve plate

over. Remove the valve plate O-ring and

discard.

STEP 3. Carefully remove connector

tubes from the heads and replace the

4 quad rings. Reassemble to the heads.

STEP 4. (Fig. #2) Remove the 4 screws

(A) securing the plastic front cover

assembly (B), and lift off the cover. Place

cover and capacitor assembly off to side

leaving it connected to the lead wires.

STEP 5. Remove the fan (D) by taking

out the screw (C) holding it to the

eccentric nib.

Figure #1

Figure #2

Set Screw

Access Hole

Capacitor

Blue

Yellow

Black

STEP 10. Make sure the lead wires are attached as shown in Fig. #11. Assemble

the front cover to the housing so that the capacitor is vertical with the leads on top.

Make sure that the wires are clear of the fan. Tighten the front cover screws to 18

in-lbs.

Figure #11

STEP 11. Remove the lter cap from the lter assemlby. Remove and discard old

lter. Replace new lter in the lter holder and snap lter cap back into place.

STEP 5. Insert the hex key into the hole in the right

side of the compressor housing (See Fig. #2). Loosen

clamping screw at the base of the connecting rod.

Slide the connecting rod off the bearing, lift it out

through the top of the compressor housing.

NOTE: It may be necessary to insert a flat tip

screwdriver into the slot in the base of the connecting

rod, and spread the base slightly, in order to break

the Loctite®bond and free it from the bearing (See

Fig. #3).

Insert Screwdriver

Figure #3

REBUILD VALVE PLATE

ASSEMBLY

STEP 1. Remove the valve keeper and

intake valve apper from the bottom of

the valve plate. Clean the bottom of the

plate with a clean soft cloth. Install the

new intake apper valve. The valve keeper

should be placed on top of the apper so

that the word “UP” is visible (See Fig. #4).

Tighten the screws to 12 in-lbs.

STEP 2. Remove the two restraints and

four exhaust apper valves (two over

each port) from the top of the valve plate.

Clean the top of the plate with a clean

soft cloth. Install the new apper valves

and screws as shown in Fig. #5. Tighten

the screws to 12 in-lbs. Set Valve Plate

Assembly aside.

Figure #4

Valve Flapper

Valve Keeper

Figure 5

Valve Flappers

Valve Restraint

STEP 9. Install the fan onto the eccentric nib. Align the slot marked ‘1007’ with the notch

on the eccentric nib. Insert the screw and washer into the threaded hole in the nib. Tighten

to 30 in-lbs. DO NOT OVERTIGHTEN. When properly assembled the fan will remain

centered in the housing when rotated by hand. NOTE: it may be helpful to insert the hex

key through the hole in the housing, and into the set screw hole in the eccentric. This

will prevent the eccentric from rotating while tightening the fan screw.

Caution

To avoid property damage or personal injury, always try rotating the fan by HAND

prior to connecting the unit to the power source. Check for suction at the air

inlet port by placing your nger over the port as you turn the fan. You should feel

a slight suction with each rotation of the fan. If you don’t feel suction, or if you

feel or hear a thump as you turn the fan, DO NOT CONNECT THE UNIT TO A

POWER SOURCE; review the assembly procedure for possible error.

Place Allan

Wrench in

Access Hole

Figure #10

Figure #8

NOTE: The purpose of the following procedure is to correctly position the connecting rod

assembly on the the motor shaft before the Loctite® bond has dried.

STEP 4. Hold the sleeve down against the housing with one hand, and slowly rotate

the eccentric with the other hand. 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 it rocks from front to rear, the

connecting rod is misaligned on the eccentric. If front to rear rocking is detected, loosen

the connecting rod clamping screw and repeat Steps 1, 2, and 3. If the connecting rod

cannot be properly aligned, contact the nearest service center.

REBUILD AND ASSEMBLY

NOTE Look down through the top of the housing, and spin the eccentric by hand. The

eccentric should run parallel to the housing ribs. If the gap between the eccentric and

housing ribs varies by more than 1/16 inch during rotation, the eccentric is misaligned.

Contact the nearest Service Center. If the eccentric is misaligned do not continue installing

the rebuild kit, as premature rod or sleeve failure may result.

STEP 2. Align the front face of the

connecting rod with the front face of the

bearing. This will result in a clearance

of about .032 inch between the rod and

the eccentric (See Fig. #7). Tighten the

clamping screw to 15 in. - lbs. torque.

DO NOT OVERTIGHTEN, or bearing

damage/connecting rod breakage may

result.

STEP 3. Slide the sleeve down until it

contacts the housing. The 4 locator ribs

should bear against the inside surface of

the sleeve and the sleeve should hold the

dust shield in place.

STEP 1. Clean the old adhesive

from connecting rod bearing

(mounted on the eccentric).

Apply Loctite® #680 (supplied)

or equivalent to the bearing bore

of the new connecting rod. (See

Fig. #2). Apply Loctite®#242

(supplied) or equivalent to the

threads of the connecting rod

screw, and turn the screw a few

turns into the new rod. Do not

tighten. Slide the dust shield onto

the rod. Drop the new rod and

sleeve assembly through the top

of the compressor housing with

the head of the rod clamping

screw to the right (as viewed

through the open end of the

compressor housing). Slip the

rod onto the bearing. Locate

the dust shield by lining up the

locator slots of the shield on the

locator ribs of the housing. (See

Fig. #6)

Figure #6

Dust Shield

Cylinder

Sleeve

Locator

Ribs

Connecting

rod

Nib

Eccentric

Bearing

Assembly

.032

Figure #7

STEP 5. Install the new O-ring into the

bottom of the valve plate assembly, seating

it rmly into the groove with your nger or

blunt object.

STEP 6. With the sleeve located and rmly

seated on the housing, replace the valve

plate as shown in Fig. #8. Make sure the

top edge of the cylinder sleeve locates

in the O-ring groove in the bottom of the

valve plate.

Figure #9

STEP 7. Clean the inside of the head with a soft clean cloth. Install the new gasket,

seating it rmly in the groove with your nger or blunt object.

STEP 8. Place the head assembly on the top of the valve plates. The exhaust port should

be facing the rear of the compressor, and the smaller cavity inside the head will be over

the curved valve restraints on the top of the valve plate. Install the 12 head screws and

tighten to 45 in-lbs. in a criss-cross pattern.