Makita Gas nailer GN900SE Manual

Models No.
Description
PRODUCT
TECHNICAL INFORMATION
CONCEPT AND MAIN APPLICATIONS
Specification
P 1/ 16
Standard equipment
Dimensions: mm (")
Width*2(W)
*2 with Hook
Height (H)
Length*2(L)
108 (4-1/4)
321 (12-5/8)
368 (14-1/2)
Note: The standard equipment for the tool shown above may differ by country.
GN900
Cordless Clipped Head Framing Nailer
Model GN900 is a cordless clipped head nailer developed for a wide range of
framing applications. The main features are as follows:
Using fuel gas as the power source to provide freedom from hoses and compressors
Equipped with LED indication lamp with battery power warning and trouble detection
functions for convenience of operation and repair
Safety goggles ............................ 1
Hex wrench 4 ............................. 1
Plastic carrying case ................... 1
Magazine capacity
Nail
44 nails (1 strip)
50 - 90
(2 - 3-1/2)
2.9 - 3.3
(0.113 - 0.131)
Clipped-head
Length: mm (")
Gauge (Shank diameter): mm (")
Head type
34 degreeNail collation angle
Optional accessories
Nail fuel pack
Fuel cell
Cleaner kit (contains the following accessories in a special Tool bag: Cleaner/ 1, Lubricating oil/ 1,
Hex wrench 4/ 1, Brush/ 1, Cotton waste/ 1)
Charger DC07SA
Charger DC10WA
Battery BL7010
7.2
1.0
30
with DC07SA/DC10WA
Li-ion
Charging time (approx.): min.
Battery
YesAnti-dry-fire mechanism
Cell
Voltage: V
Capacity: Ah
Battery life*4
Fuel cell life*5
4,000 nails (approx.)
Motor*3Coreless DC motor
1,200 nails (approx.)
3.2 (7.0)
3.4 (7.5)
without Battery and Fuel cell
with Battery and Fuel cell
Net weight: kg (lbs)
W
H
L
This product is available in the following variations.
The model also includes the accessories listed below in "Standard equipment".
GN900SE
GN900S DC07SA
Model No. type
No
Charger
No
quantity
No
1
2
BL7010
(Li-ion 1.0Ah)
Battery*1
GN900ZK
*3 The motor is used for gas mixing, air intake/exhaust, supply of cooling air.
*4 Battery life: the number of nails on a single full battery charge
*5 Fuel cell life: the number of nails per Fuel cell
*1 Battery is used as the power source for ignition spark,
gas mixing, air intake/exhaust and supply of cooling air.

P 2/ 16
Repair
CAUTION: 1) Remove Battery, Fuel cell, Nail from the machine for safety before repair/ maintenance
in accordance with the instruction manual!
2) Loosen Hex socket head bolts with L-shape wrench in advance before removing them
using cordless impact driver with 1R228/ 1R229, or the top of 1R228/ 229 will damage.
[1] NECESSARY REPAIRING TOOLS
[2] LUBRICATIONS AND ADHESIVES
Fig. 1
Code No. Description Use for
1R005 Retaining ring pliers RT-2N Disassembling / Assembling Retaining ring R-58
1R228 1/4” Hex shank bit for M4 Disassembling / Assembling M4 Hex socket head bolt
1R229 1/4” Hex shank bit for M5 Disassembling / Assembling M5 Hex socket head bolt
1R268 Spring pin extractor 3 Disassembling / Assembling Spring pin 3-32
1R291 Retaining ring S and R pliers Disassembling / Assembling Retaining ring R-24
Item No.
Apply a little amount of Lubricant and Adhesives illustrated in Fig. 1.
Description Portion to lubricate Lubrication
Lubrication oil VG100
Lubrication oil VG100
Molybdenum
disulfide
a: Inside with which Driver complete contacts
b: Outside with which Chamber contacts
24
42
23
Cylinder ring Whole portion
O ring 60 Whole portion
Cylinder
24
b
b
42
23
17
9
c
67
97
a
ThreeBond1342
or
Loctite272
c: Rib portion on which
Exhaust plate is attached
23 Cylinder
Item No. Description Adhesive
ThreeBond
1215
Portion to glue
Thread
Driver complete
Exhaust plate
Chamber
M5x10 Hex
socket head bolt
M5x16 Hex
socket head bolt
M5x35 Hex
socket head bolt
9
97
17
67

P 3/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Driver, Front cushion
DISASSEMBLING
1) Remove M5x35 Hex socket head bolt (2pcs.)
Note: Sleeve 8 (2pcs.) may be
fallen from Handle set
in the disassembling step.
Therefore, pay attention
not to lose Sleeve 8.
1) Remove Retaining ring (INT) R-58 from Cylinder with 1R005.
2) Remove M5x25 Hex socket head bolt (4pcs.) and Top cap.
3) Hold Housing by hand and slide it straightly
and gently in order not to hook with Fan 60,
then lift Housing obliquely as designated in
black arrow.
Note: Do not deform Fan 60.
Handle set
Top cap
Cylinder head
Fan 60
M5x35 Hex socket
head bolt (2pcs.)
M5x25 Hex socket
head bolt (4pcs.)
Housing
(1) Disassemble Driver complete as illustrated in Figs. 2 and 3.
Fig. 2
Fig. 3
Sleeve 8
cylinder 1R005 Driver complete
Retaining ring (INT) R-58 on Cylinder
3) While holding Piston ring (2pcs.)
with the slotted screwdriver to
prevent them from being caught
in the groove for Retaining ring
(INT) R-58, push Driver complete
with another slotted screwdriver
toward Top cap side.
2) Insert slotted screwdriver along with
an vertical groove of Cylinder.
slotted
screwdriver
vertical groove
of Cylinder
Cylinder viewed from top cap side
Inside view
slotted screwdriver
end of Driver complete
Piston ring (2pcs.)
on Driver complete

P 4/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Driver, Front cushion (cont.)
DISASSEMBLING
ASSEMBLING
M5x10 Hex socket
head bolt (2pcs.)
Separate Cylinder section from Housing after removing
Arm plate, Contact top and Front plate.
(2) Separate Cylinder section from Housing. And then disassemble Front cushion. (Fig. 4)
(1) Assemble Front cushion to Cylinder as illustrated in Fig. 5.
(2) Mount two Piston rings to Driver complete. (Fig. 6)
M5x16 Hex socket
head bolt (3pcs.)
Arm plate
Contact top
Front plate
Housing
Front cushion
Push Front cushion into Cylinder
with hammer until it stops.
Insert slotted screwdriver
from the nail exit side,
and push Front cushion
out of Cylinder section.
Fig. 4
Cylinder
section
Front cushion
hammer
more than
90 degrees
Assemble Piston ring (2pcs.) to Driver complete
so that the angle of their slits is more than 90 degrees.
slit
slit
slit
slit
Cylinder
Driver complete
Fig. 5 Fig. 6
Contact top Contact top
Use slotted screwdriver to prevent
Piston rings from being caught in
the groove of Cylinder for
Retaining ring (INT) R-58.
(Refer to Fig. 3.)
Set Driver complete in place
so that the flat tip faces
Contact top installation side.
Note: Do not face the chamfered tip
of Driver complete to Contact top
installation side
(3) Insert Driver complete into Cylinder as illustrated in Fig. 7.
(4) Inserting Cylinder section into Housing, tighten Front plate with M5x16 Hex socket head bolt (3pcs.).
Assemble Contact top and Arm plate. (Fig. 4)
(5) Assemble Retaining ring (INT) R-58 to the groove in Cylinder. (Fig. 3)
(6) Assemble Handle set to Housing. (Fig. 2)
Fig. 7

P 5/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Exhaust valve section
DISASSEMBLING
When the tip of Driver complete does not hit the nail head in use, disassemble exhaust valve section to check malfunctions
as illustrated in Fig. 8.
Fig. 8
Exhaust valve is attached to four holes on Exhaust plate
when Driver complete moves to the lowest position.
Exhaust plate under Exhaust valve seals Cylinder
at the frame on Cylinder.
Exhaust plate
Exhaust valve
Exhaust valve
Punching metal
Exhaust plate
Exhaust plate
Exhaust cover M4x10 Hex socket
head bolt (2pcs.)
M4x10 Hex socket
head bolt (2pcs.)
Exhaust valve
Silencer
Silencer
Cylinder
Disassemble Exhaust cover, Silencer and Exhaust valve.
Silencer
frame on Cylinder
frame on Cylinder
frame on Cylinder
Exhaust plate
It causes the wrong driving like dry fire and the leakage of gas.
Note: It is possible that the tip of Driver complete does not hit the nail head in use because of the corrosion of adhesive
even if Exhaust valve and Exhaust plate do not look deformed/ damaged.
Scrape away the adhesive and apply fresh ThreeBond to treat such a case. (Refer to next page.)
Exhaust valve Deformed and damaged Exhaust valve / Exhaust plate
Normal condition of Exhaust valve and Exhaust plate
(1) Disassemble Handle set from Housing. (Fig. 2.)
(2) Remove Contact top, Arm plate and Front plate from Cylinder. And separate Cylinder section from Housing. (Fig.4)
(3) Disassemble Exhaust mechanism as illustrated in Figs. 9 and 10.
Fig. 9 Fig. 10

P 6/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Exhaust valve section (cont.)
ASSEMBLING
Apply ThreeBond 1215 on the frame of
Cylinder as illustrated below.
applied portion of
ThreeBond 1215
Note: Wait until ThreeBond 1215 drys at least three hours, and then try nailing before actual work.
Incomplete drying causes the leakage of gas.
Set Punching metal
in place.
Attach Exhaust plate and tighten it with
M4x10 Hex socket head bolt (2pcs.)
so that the protrusions face Exhaust valve
installation side.
Punching
metal
Exhaust plate
protrusions of
Exhaust plate
Exhaust plate
M4x10 Hex socket
head bolt (2pcs.)
M4x10 Hex socket
head bolt (2pcs.)
Exhaust valve
Exhaust valve
Set Exhaust valve and Silencer in place. Tighten Exhaust cover with M4x10
Hex socket head bolt (2pcs.)
Silencer
Exhaust cover
Fig. 11
Fig. 12
Punching metal frame of Cylinder
(1) Use slotted screwdriver to scrape away adhesive left on the frame on Cylinder.
Note: The incomplete scraping causes the leakage of gas.
(2) Take the assembling step as illustrated in Figs. 11 and 12.
(3) Insert Cylinder section to Housing and assemble Front plate.
Assemble Contact top and Arm plate to the Driver guide section of Cylinder. Refer to Fig. 4.
(4) Assemble Handle set to Housing as illustrated in Fig. 2.

P 7/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-3. Chamber
DISASSEMBLING
(1) Disassemble Handle set from Housing as illustrated in Fig. 2.
(2) Remove Contact top, Arm plate and Front plate from Cylinder.
Separate Cylinder section from Housing as illustrated in Fig. 4.
(3) The removed Cylinder section can be disassembled as illustrated in Figs. 13 and 14.
1R268
Chamber
Chamber
Arm
Arm connector
While opening Arm’s ends,
pull Arm in the direction
designated with black arrow.
M4x16 Hex socket head bolt (4pcs.)
Remove Chamber top
and Chamber seal ring
from Chamber
Chamber top
Cylinder
Cylinder
Chamber
Pull Chamber carefully so that Compression
spring 8 does not spring out of Cylinder.
Remove these Spring pin3-32 (2pcs.) for joining Cylinder section
and Chamber.
Spring pin 3-32 (2pcs.)
Compression
spring 8 (2pcs.)
Stop
rubber (2pcs.)
Pay attention not to
strike Chamber.
Cylinder ring
Chamber seal ring
Arm
Note: Pay attention not to
lose Arm connector.
Fig. 13
Fig. 14

P 8/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-3. Chamber (cont.)
ASSEMBLING
Assemble Cylinder rings to Cylinder so that
the angle of the two notches is more than 90 degrees.
Cylinder ring (2pcs.)
(1) Assemble Cylinder rings to Cylinder as illustrated in Fig. 15.
Note: Apply the specific lubricants in accordance with the instruction shown in Fig. 1.
Cylinder
(2) Put Chamber seal ring on the edge of Chamber, and assemble Chamber top to Chamber by fastening with M4x16
Hex socket head bolt (4pcs.). Refer to the right illustration in Fig. 14.
(3) Setting Arm connector to Arm, assemble them to Cylinder. Refer to the left illustration in Fig. 14.
(4) Assemble Stop rubber and Compression spring 8 to Cylinder. Refer to the right illustration in Fig. 13.
(5) Applying Molybdenum disulphide lubricant to the outside of Cylinder (Fig. 1), insert it into Chamber.
Refer to right illustration in Fig. 13.
(6) Connect Cylinder with Chamber as illustrated in Fig. 16.
Fig. 15
Fig. 16
Spring Pin 3-32
Water pump pliers
Insert Spring pin 3-32 for approx. 5mm depth
with aligning two holes of Chamber with those of
Cylinder for Spring pin 3-32.
And then, set Spring pin 3-32 in place with water
pump pliers.
Insert the other Spring pin 3-32 in the same manner.
(7) Inserting Cylinder section into Housing, tighten Front plate with M5x16 Hex socket head bolt (3pcs.). Refer to Fig. 4.
(8) Assemble Contact top and Arm plate. Refer to Fig. 4.
(9) Assemble Handle set to Housing. Refer to Fig. 2.

P 9/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-4. Pusher, Handle section
DISASSEMBLING
M5x10 Hex socket head bolt
Fig. 17
Fig. 18
Note: Lock bar and Compression spring 4 easily fall off in this step.
Pay attention not to lose Lock bar and compression spring 4.
2. And then remove the following screws.
* M5x10 Hex socket head bolt
* 5x25 Tapping screw (3pcs.)
Handle set (L) and Nail feeding section
can be separated from Handle set (R).
Sliding Pusher lever toward the rear side,
insert Screwdriver to stop Pusher lever’s return.
Remove Lock bar and compression spring 4.
Lock Bar
Pusher lever
Compression spring 4
(1) Separate Handle set from Housing as illustrated in Fig. 2.
(2) Handle set (L) can be separated from Handle set (R) as illustrated in Fig. 17. And remove Lock bar
and Compression spring 4 as illustrated in Fig. 18.
Magazine support
Handle set (R)
Nail rail
Nail feeding section Handle set (L)
5x25 Tapping
screw (3pcs.)
Magazine
support
1. Pressing the end of Handle set,
remove Magazine support by
sliding it toward rear side.
Handle set (L)

P 10/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-4. Pusher, Handle Section (cont.)
DISASSEMBLING
(3) Pusher section can be disassembled from Handle set (L) as illustrated in Fig. 19.
(4) The other parts in Handle set can be disassembled as illustrated in Fig. 20.
M4x20
Pan head screw
Remove Pusher, Pusher holder Compression and spring 4
from Pusher lever by unscrewing M4x20 Pan head scerw.
Remove Spiral spring complete from
Drum portion of Pusher lever
Pusher
Handle set (L)
Spiral spring complete
Pusher holder
Lock claw of
Spiral spring
Pusher lever Pusher Lever
Compression
spring 3
Drum portion
Fig. 19
Fig. 20
Hook holder Hook
Lead wire cover
Spark unit
Switch Unit
Chamber Lock Bar
Line Filter
Battery case
Trigger

P 11/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-4. Pusher, Handle section (cont.)
ASSEMBLING
Hook Spiral spring complete
to Handle set (L) with its claw.
Insert drum portion of Pusher
lever into Spiral spring complete,
and slide Pusher lever to the
suitable position.
Keeping the suitable position,
fasten Pusher holder to
Pusher lever with M4x20 Pan
head screw.
Spiral spring
complete
Spiral spring
complete
Pusher lever
Under driver guide
Nail rail
tab of
Nail rail
Nail plate
Facing the cut portion to Under driver guide,
assemble Nail plate.
Facing the tab to
Under driver guide,
assemble Nail rail.
cut portion of Nail plate
Pusher holder
M4x20 Pan head
screw
Fig. 21
Fig. 22
(1) Assemble Pusher section as illustrated in Fig. 21.
(2) Referring to Fig. 18, assemble Lock bar and Compression spring 4 to Handle set (L).
(3) Assemble Nail feeding section as illustrated in Fig. 22.
(4) Referring to Fig. 20, assemble the necessary parts to Handle set (R).
(5) Referring to Fig. 19, assemble Nail feeding section, and fasten Handle set (L) to Handle set (R)
with 5x25 Tapping screws (3pcs.) and M5x10 Hex socket head bolt. Assemble Magazine support.
(6) Assemble Handle set to Housing as illustrated in Fig. 2.

P 12/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-5. DC motor and Spark plug
DISASSEMBLING
(1) Separate Handle set from Housing as illustrated in Fig. 2.
(2) Disconnect Spark plug and DC motor from Spark unit and Terminal as illustrated in Fig. 23.
(3) DC motor can be removed from Cylinder head as illustrated in Figs. 24 and 25.
Remove Plug cap from Spark plug.
1. Remove Spark plug with 8mm box wrench.
2. Disconnect Earth terminal
3. Disconnect Connectors of DC motor.
Plug cap
Spark plug
Spark plug
O ring 10
Connectors
Earth terminalM4x8 Pan head screw
Fig. 23
Fig. 24
Fig. 25
Remove Fan 60 by unscrewing M3x4 set screw. Remove Retaining ring R-24 with 1R291 while passing
Motor’s lead wires through the Retaining ring.
Fan 60
Motor sleeve
M3x4 Set screw
DC motor
Flat washer 10, Conical
compression springs 12-18,
DC Motor and Motor sleeve
can be removed from Cylinder
head.
Flat washer 10
Steel ball 3
Conical
compression
spring 12-18
Flat washer 10
Conical compression spring 12-18
Conical compression spring 12-18
Retaining ring R-24
DC motor
Pull Lead wires of DC motor through
Flat washer 10 and Conical compression
spring 12-18.
And remove Epoxy washer 2 from
Motor shaft.
Epoxy washer 2

P 13/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-5. DC motor and Spark plug (cont.)
ASSEMBLING
Flat washer 10
Retaining
ring R-24
Pass Motor’s Lead wires through Conical compression
spring 12-18, Flat washer 10 and Retaining ring R-24.
And assemble Epoxy washer 2 to Motor shaft.
After putting grease to Steel ball 3, assemble Steel
ball 3 to DC Motor.
Facing the Steel ball to the slit of Motor sleeve,
insert the DC motor into Motor sleeve.
Put the another Conical compression spring 12-18
into Motor box as illustrated above.
Assemble DC motor covered with Motor sleeve while
paying attention to the descriptions in Fig. 27A
Conical compression
spring 12-18
DC. motor
(1) Assemble DC Motor to Cylinder head as illustrated in Figs. 26, 27 and 27A.
Top view of Cylinder head and DC motor
Epoxy
washer 2
Protrusion of
Motor sleeve
Steel ball 3
Groove of
Motor box
Fitting the Protrusion of Motor sleeve to either of the grooves of Motor box,
assemble DC motor to Cylinder head.
Motor box of Cylinder head
Steel ball 3
Motor sleeve
Slit
Fig. 26
Fig. 27
Fig. 27A
Conical compression spring 12-18
Motor box

P 14/ 16
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-5. DC motor and Spark plug (cont.)
ASSEMBLING
Note: Conical compression springs 12-18 have to be assembled as mentioned below and shown in Fig. 28.
DC Motor
Fan 60 side
Top cap side
Fig. 28
Conical compression spring 12-18
(See the left illustration in Fig. 26.)
Conical compression spring 12-18
(See the left illustration in Fig. 27.)
(2) In order to fix DC Motor, assemble Retaining ring R-24 with 1R291, while pressing down the upper Conical
compression spring 12-18. Refer to the right illustration in Fig. 24.
(3) Assemble Fan 60. Refer to the left illustration in Fig. 24.
(4) Connect the connectors of DC Motor in the Handle set. Refer to the right illustration in Fig. 23.
(5) Connect Body earth terminal to Cylinder head. Assemble O ring 10 and Spark plug to Cylinder head.
Refer to the right illustration in Fig. 23.
(6) Connect plug cap to Spark plug. Refer to the left illustration in Fig. 23.
(7) Assemble Handle set to Housing. Refer to Fig. 2.
[4] How to check of Spark and DC motor
(1) Separate Handle set from Housing as illustrated in Fig. 2. And Disassemble Handle set (L) as illustrated in Fig. 17.
(2) Remove Fan 60 from DC Motor as illustrated in Fig. 24.
Note: Be sure to remove Fan 60 for safe maintenance.
(3) Setting Battery to the machine, start the following tests.
* Ignition by pushing the terminal of Switch unit A See Fig. 29.
* DC Motor by pushing the terminal of Switch unit B See Fig. 29.
Fig. 29
DC motor
Spark plug
Spark plug makes a spark when
the terminal of Switch unit A is pushed.
DC motor runs for seven seconds when
the terminal of Switch unit B is pushed.
It proves DC motor is in order.
It proves Ignition is in order.

P 15/ 16
Repair
[5] Diagnosis by Indication lamp
Color of the indication lamp means the followings.
Blinking green: Normal status
Blinking red: Need to recharge the battery cartridge
Lighting-up-red: Recharge the battery cartridge. Nailing can not be performed due to no remaining battery capacity.
Blinking orange after blinking green and red alternatively
for 10 seconds: Fault detection is running. Remove and reinsert the battery cartridge to reset. If fault detection is
running again, it is malfunction condition as shown in Fig. 30.
Fig. 30
Number of
blinking orange
Melting a part of Switch in Contact arm / Disconnection of Trigger switch Returning Contact arm incompletely1
Melting a part of Switch in Contact arm / Melting a part of Trigger switch Returning Trigger incompletely2
Possible electrical-malfunction Possible mechanical-malfunction
Melting a part of Switch in Contact arm Returning Contact arm incompletely3
Melting a part of Trigger switch4
Disconnection of DC motor5
Malfunction on Spark unit6
Circuit diagram
Fig. D-1
Color index of lead wires' sheath
Black
Motor
Spark plug
Line filter
Spark unit
Earth terminal for
connecting to Housing
White
Red
Connector
Connector
Band
Terminal
Switch unit for DC motor
Yellow
Switch unit for Trigger
Flag
receptacle
Straight
receptacle

Wiring diagram P 16/ 16
Terminal
Terminal
Put sag of Connecting lead wire
to Spark plug in this position.
Put lead wires
into lead wire
holders.
Fix lead wires (yellow, black) of
Spark unit with these lead wire
holders without putting sags.
Wind lead wires (red and black) to Line filter one time,
passing them through Line filter. And connect them to
connector of DC Motor.
Flag
receptacle
Straight receptacle
Facing the wire connecting portion to plus mark side,
connect Flag receptacle to Minus terminal.
Line filter
boss
rib
Lead wire to Spark plug has to be pulled
out by 70 up to 75mm from the opening
of Handle set (R).
Put lead wires (black, red)
for DC motor between
Switch unit and boss.
Put lead wire (black) of
Spark plug between rib
and boss.
Switch unit for DC motor
Switch unit for trigger
Connector
Connector to
DC motor
Wire connecting portion
Spark unit
Pay attention not to put
lead wires on the rib in
this area.
Line filter
When putting the following
lead wires into lead wire holders,
do not cross them in this area.
* lead wire (red) to DC motor
* lead wire (black) to DC motor
* lead wire (white) to Switch unit
for DC motor
* lead wire (black) to Switch unit
for DC motor
70 up to 75 mm
Fig. D-2
Wiring in Handle set (R)
Wiring on Cylinder head
Fig. D-3
Pass DC motor’s lead wires (red, black)
through the notch of the rib for setting
DC Motor.
Spark plug
Connector
Put Connector and sag of
lead wires in this position.
Lead wire to Spark plug has to be put
on the other lead wires viewed from
Top cover side.
DC motor
Earth terminal