RAMSET RA27 User manual

07.2019
RA27 TOOL
SERVICE MANUAL

07.2019
The Model RA27 troubleshooting/service manual has been developed to assist ITW
CCNA field sales and distributor field/service personnel in servicing the RA27 powder
actuated tool. This manual is designed to reduce the amount of tool down time when a
problem occurs by giving field and service personnel troubleshooting techniques and the
proper corrective measures to take. In many cases, servicing can be done right at the
job site in a very short time. This manual can also be used as an educational tool for
teaching perspective operators and service personnel on the inner workings of the tool
and proper service techniques. Using this manual wisely will reduce tool down time,
promote customer confidence and allow more quality time for selling.
This manual is broken into 5 chapters with 2 sections on tool disassembly / assembly:
1. Introduction
2. Troubleshooting
3. Tool Disassembly
a. Front End
b. Firing Pin/Backend
4. Tool Schematic
5. Glossary
When troubleshooting, or servicing a tool it is important to understand the function of
each component. Knowing the function of each component will quickly lead to the
troubled area. It is also important to be able to accurately describe a condition using the
correct terminology.
When troubleshooting, or servicing a tool it is always important to function test the tool
first. Always check the tool first to make sure that it does not contain a live load.
Test the tool several times by depressing the muzzle bushing fully on a hard surface
such as a workbench or concrete floor and actuate the tool. You should hear an audible
click as the firing pin releases. Let up on the tool and check to be sure the barrel has
opened to the full open position. This function test may lead you to the proper area of
the tool needing service.
When attempting any repair on a Ramset tool, be certain you have read and understand
the operator’s manual, you have the correct tools to perform the repair, and have/wear
the correct personal protective equipment for the circumstance.
Many powder loads contain lead. Lead residue within the tool is a possibility. Proper
personal protective equipment (PPE) must be worn.
There may be cases where this manual may not supply the information needed, or the
user may need additional information. For further information, the ITW Service and
Parts Center or Ramset Technical Service can be contacted.
Further information on obtaining parts can be found at www.itwconstructionparts.com or
www.ramsetrepair.com
1

07.2019
The troubleshooting section is intended to direct the user or repair technician to
some of the more probable occurrences that may exist in the tool. It does not list
all possible occurrences. To master the repair of any tool you must first know
and understand how each part functions. The basic symptoms, probable causes
and solutions are listed below.
Tool stuck in closed position and piston tip at end or protruding from the tool.
Cause –tool was overdriven or debris caught in front end
1. Inspect Front end components for damage/debris
Chipped piston
Bent piston
Fastener debris
2. Replace Buffer Assembly
Tool lacks power, may experience “poof” or “dud” loads, or fastener stand-off
Cause –piston not fully returning or dropping before taking a shot
1. Note where power adjust level is at, Inspect power adjust
mechanism.
2. Clean Piston and Barrel Assembly
3. Inspect pawls, replace
4. Inspect piston for wear or damage
5. Inspect/replace retention ball and clip in muzzle
Tool clicks or fires once and next load does not advance
Cause –Check strip tracks and load advance lever
1. Clean residue build-up in strip tracks
2. If load strip does not move at all, replace advance lever assembly
Tool skips powder loads
Cause –Tool front end is not fully compressed before the trigger is pulled
1. The front end must be fully compressed before the trigger is pulled.
NOTE: End users moving too quickly can anticipate the shot and back
off the front end before or at the same time the trigger is pulled.
2. If the tool is equipped with a magazine, the magazine may not be fully
closed/depressed prior to pulling the trigger. This could be due to
debris within the magazine or improper magazine function.
Fastener frequently breaks during installation
Cause –End of piston excessively worn or trying to shoot at an angle
1. Instruct user on proper 90-degree tool placement/operation
2. Replace Piston
3. Inspect end of fastener guide for wear, replace if necessary
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07.2019
Depress tool, tool does not click and load does not fire
Is the barrel fully closing? If No
1. Barrel installed backward
2. Front Collar not installed correctly
3. Pawls incorrectly positioned behind piston
4. Debris in receiver or around barrel
5. Cocking rod loose/damaged
Tool is difficult to close the front end or sticks at times
Cause - Tool is dirty or has a broken component
1. Clean front end of tool
Follow instruction in this manual
Follow instruction in RA27 operator’s manual
Watch video on Ramset You Tube channel
Tool trigger does not fully return.
Cause –Tool strip tracks are dirty
1. Clean tracks where powder load strip rides through tool
2. Damaged advance lever or advance lever spring

RA27 SERVICE FRONT END
The result of a problem in the front barrel assembly is inconsistent fastenings or
premature damage to any of the component parts. The front barrel assembly is the
simplest part of the tool to service and maintain; however, it does require the greatest
amount of servicing. Ramset recommends cleaning the front barrel assembly after each
day’s use. This section will provide a guide to evaluating problems, taking corrective
actions and prevent further problems.
Inconsistent Fastenings
Inconsistent fastenings are caused by variations in the chamber volume from shot to
shot. Simply put, the piston does not fully return after each shot. The level of
inconsistency can vary from a “poof load” or “dud shot” to variations in fastener
penetration.
In the RA27 piston reset is accomplished with two components, the pawls and fastener
guide with integrated retention clip and ball. Inconsistent fastening is likely to be caused
by dirt and debris preventing the piston from falling back into position. Damage to the
pawls may also be a contributing factor. The pictures on the following pages show how
to disassemble the front end and diagnose the components.
Damage to Front End Components
When a tool needs service with damaged front end components, there is not much
troubleshooting involved. The problem is typically obvious, broken parts. It is important
to understand what caused the failure and what to do to prevent the damage from
happening again. This damage is likely caused due to misapplication or misuse of the
tool. The pictures on the following pages show how to disassemble the front-end
components. Function testing the tool before and after servicing the tool will help
diagnose the issue and can assure the problem is corrected. Instructions on tool
function testing can be found in the operator’s manual. Additional instructions for front
end service of the RA27 tool can be found in the Operator’s Manual.
3a

RA27 SERVICE FRONT END
RA27 Front End Disassembly
1. Be sure the tool is unloaded!
Grasp the knurled collar and
unscrew the Fastener Guide
Assembly. Once unthreaded,
pull it from the tool.
While the single pin muzzle is
shown, the magazine is removed
in the same manner
2. On the Barrel Retention Collar,
locate the raised lines on the side
and top of tool. Turn the barrel
collar 90 degrees so that the side
mark on the collar is aligned with
the top mark on the tool. Lift off
the collar. A rubber strap wrench
may be needed to turn the collar.
3. Grasp the Barrel Assembly and
then pull open the two pawls.
Use caution as the barrel is under
light spring pressure. Note that
the pawl assembly is hinged and
not removed from the tool.
4. Remove the Barrel and Spring
from the tool housing.
Inspect the Pawls. Remove any
powder residue from the Pawls
with a small wire brush. Any
large chips or breakage would
indicate the need to replace the
pawl.
5. Remove the Barrel Spring and
Piston from the Barrel Assembly.
There is no need to disassemble
the Fastener Guide Assembly. If
damaged, it is replaced as an
assembly.

RA27 SERVICE FRONT END
6. Inspect the front end
components. Check the Piston is
straight and free of chipping on
the fastener striking end. Photo
to the left shows a damaged
piston. Note worn tip and slight
bend.
7. Clean the front end components
with a wire brush. Ramset part
number PATCK contains a
variety of wire brushes to assist
with cleaning the RA27 tool and a
variety of other powder actuated
tools.
8. Industrial spray solvents or
automotive brake cleaners that
are safe for plastic can be used
to remove other oils and debris.
The use of any lubricant on
reassembly is not recommended.
Should the tool sit un-used for a
long period of time, an oil can be
used on the outer surfaces of the
metal parts provided the parts are
wiped dry before reassembly.
Excess oil or lubricants will attract
powder residue and increase
maintenance frequencies.
9. To speed up the cleaning
process, a wire wheel mounted to
a bench grinder can be used to
clean the outer surfaces.

RA27 SERVICE FRONT END
10.A round, wire tube brush is used
to clean the inner surfaces. The
looped handle end of the brush
can be removed and chucked
into a drill to speed up cleaning of
the inner surfaces; i.e. inside of
the Barrel, inside of the Receiver,
Fastener Guide, Power Adjust
Hole, etc.
11.Clean the Load Chamber with a
wire brush. After cleaning,
should the barrel stick closed on
the first shot, it may be necessary
to polish the load chamber with a
polishing bob and an extra
smooth/fine lapping paste.
12.To reassemble, place the Piston
into the Barrel. Piston should be
pushed all the way to the back of
the Barrel.
13.Insert the Buffer into the end of
the Fastener Guide as shown.
Push into place until the rubber
lip at the front of the Buffer
engages into the slot inside the
Fastener Guide
14.Place the Barrel Spring over the
end of the Barrel
15.Note the slot in the top of the
Barrel. This should align with the
top of the Housing. This slot
allows the Barrel to go in one
way.
16.Be sure the Pawls are open and
insert Barrel back into tool
housing. Once fully inserted,
push the Pawls into place. Hold
the two pawls in the closed
position until the retention collar
is installed.

RA27 SERVICE FRONT END
17.While holding the Pawls, slide the
Retention Collar over the Barrel.
Align the Collar so the side notch
is aligned with the top notch in
the housing. Then slide over the
thread area. Once fully
positioned over the threads, turn
the collar 90 degrees so the
notches align on the side
18.Retention Collar is fully installed.
Note notches on the side.
19.Install Fastener Guide assembly.
Position Fastener Guide over
Barrel. Apply slight pressure to
the top side of the fastener guide
while threading the knurled collar.
It helps to firmly push the
Fastener Guide onto the Barrel
before threading. This will help
seat the Buffer into the Barrel and
allow engagement of the first
thread.
20.As you are tightening the knurled
collar on the muzzle, you should
feel the part begin to tighten
against the rubber O-ring inside
the collar. If the muzzle is
properly installed, the shroud
should click when turned or
indexed.
21.Should the tool use a Magazine
instead of the Fastener Guide,
the Magazine is installed in the
same way.

RA27 SERVICE BACK END / ADVANCE LEVER
This next section covers service on the backend of the RA27. Should the tool
experience problems with load advancement, or problems within the firing mechanism,
the following steps will guide you through replacing the various components and
thoroughly cleaning the backend assembly. Before beginning, make sure the tool is
unloaded. It is also recommended to remove the front-end components. Follow the
previous section for further information on how to do this.
1. Begin by removing the rubber
Backend Cover from the rear of
the tool. The cover is held in
place by a rubber tab feature
fitting into a recess in the rear
hook assembly plate. Locate an
edge of the cover and pry it off by
hand.
2. Under the Backend Cover there
are three screws, one holding the
belt hook and the other two at
12:00 and 6:00 are to be
removed to gain access to the
back components. Use a 5/32”
or 4mm hex key wrench to
remove these screws.
NOTE: There is spring force
under this plate. Use caution
when removing these screws.
It is not necessary to remove the
screw holding the belt hook in
place. The back cap can be
removed with this screw in place.
3b

RA27 SERVICE BACK END / ADVANCE LEVER
3. After loosening the screws, pull
the plate back noting its
orientation. There are two spacer
sleeves that the screws go
through. These sleeves stick in
the Mech. Housing or could come
off with the plate.
4. To remove the Rear Handle Grip,
turn the tool over and locate the
screw at the base of the handle.
Using a 3mm hex key wrench,
remove the screw.
5. Once the screw is removed, slide
the Rear Handle Grip back and
remove it from the tool housing.
6. The folding Swivel Hook can be
removed at this point. Note one
part of the hook fits into the
orange housing the other part fits
into the Rear Handle Grip.

RA27 SERVICE BACK END / ADVANCE LEVER
7. When removing the Swivel Hook,
note that there is a small spring
that fits over the post on the hook
and is contained in the rear
handle grip
8. Remove the Strip Compartment.
This has a small amount of spring
pressure behind it from the
Trigger Spring. Slightly push
down and maneuver the
Compartment from the orange
housing. Next remove the
Trigger Spring from the backside
of the trigger.
9. Before removing the Mech.
Housing Assembly, take note of
the position of the Releaser,
Releaser Spring and position of
other components in the back
end.
10.The Mech. Housing Assembly
can now be removed from the
tool housing as a complete
assembly. Pull the trigger as you
normally would to fire the tool.
This will push the Mech. Housing
Assembly back to where it can be
removed from the tool.

RA27 SERVICE BACK END / ADVANCE LEVER
11.The following photos are for
reference to note position of
components.
12.Mech. Housing Assembly
removed from tool housing.
Note the use of grease in several
places in the Mech. Housing.
The small amount of grease will
help lubricate moving parts
13.Note position of the control rod
and control rod spring.
14.Advance lever side of the Mech.
Housing Assembly.

RA27 SERVICE BACK END / ADVANCE LEVER
15.The Receiver Assembly should
begin to slide out the front. The
pawls hang off one of the ribs on
the Receiver. As the Receiver is
removed from the Housing, the
pawls should fall out of position.
16.Note the pawls just fall out of
place.
The pawls collect a fair amount of
residue. Be sure to remove the
residue to allow for smooth
operation with the barrel
assembly
17.As you remove the Receiver
assembly from the plastic
housing, note its orientation with
the cut-out at the top on the
advance lever side.

RA27 SERVICE BACK END / ADVANCE LEVER
18.The next series of photos show
the disassembly of the Mech.
Housing assembly.
Note the use of grease in areas
of movement. As the parts are
cleaned and reassembled, the
grease should be applied in these
areas for smooth operation. A
white lithium grease or similar
with a wide working temperature
of 0°F to 300°F or better should
be used.
CRC SUPER WHITE™ MULTI-PURPOSE
LITHIUM GREASE No. SL3150
19. Note the Releaser and Releaser
Spring. Note the orientation on
the ends of the spring. The photo
below shows a different installed
view. The releaser is pointed at
the 12 ‘o-clock position, with the
spring ends holding it in position
20.Firing pin, Releaser and Releaser
spring removed.

RA27 SERVICE BACK END / ADVANCE LEVER
21.Find the power adjust dial
assembly. Unthread this from the
indicator slider.
22.Note that there is a ball detent
under the threaded portion.
23.Remove the Control Rod. Note
the orientation of the spring on
the end of the control rod.

RA27 SERVICE BACK END / ADVANCE LEVER
24.On the opposite side of the
Mechanism housing is the
advance lever. Inspect the
advance lever for straightness
and determine it is not bend or
damaged.
One reason a tool may not
advance the load is dirty strip
load tracks. A damaged advance
lever could be another cause.
25.Loosen the Nyloc hex nut to
remove the Advance Lever and
Spring

RA27 SERVICE BACK END / ADVANCE LEVER
26.The Mech. Housing can be
cleaned in a variety of ways.
Find a cleaner that is safe for
plastic material and will dissolve
the grease and debris.
27.After cleaning the Mech. Housing
and its associated parts,
reassembly can begin. The next
several photos are for reference
in placement of the various
components. Refer back to some
of the disassembly photos for
further reference.

RA27 SERVICE BACK END / ADVANCE LEVER
28.Note the position of the spring
ends. One end of the spring
rests on the Control Rod Key, the
other on the tab of the Mech.
Housing.
Note position of the Control Rod
Key and the arm on the Trigger.
As the Trigger is pulled back
against the Control Key, the
Control Key should rotate itself
and the Control Rod.
Once fully assembled, set the
Mech. Housing aside for a
moment.
29.Clean the Outer Housing, Pawls
and Receiver. Reassemble
these components into the front
of the Housing.
Note the position of the Barrel
Stop in the Receiver (Arrow)
Fully seat Receiver into Housing.
The Pawl Stop should be covered
by the Housing.
30.Take the fully assembled Mech.
Housing and place it back into
the orange Tool Housing until it
stops. It will stop short of being
fully inserted.

RA27 SERVICE BACK END / ADVANCE LEVER
31.The Mech. Housing will stop at a
point where the advance lever is
against the rear part of the
receiver.
32.Push the Trigger and make the
Link Rod move to the end. The
photos below show additional
detail
Receiver
Assembly
Advance
Lever
Link Rod