HOW TO USE THE GH-780
Attach the proper pulling head securely to the GH780 (see
Pulling Heads, page 5). Insert the rivet stem into the pulling
head until the head of the rivet is in contact with the pulling
head sleeve. This will ensure full engagement between the
jaws and the rivet stem and will prevent slippage.
Insert the rivet into the application and pull the trigger to acti-
vate the tool. Upon release of the trigger, the stem will
release to the rear of the tool. Ensure that the pin deflector (12)
is in place. To prevent FOD (foreign object debris), use a
mandrel catcher bag (13). (Must be ordered separately).
MAINTENANCE AND REPAIR
The GH-780 has been manufactured to give maximum
service with minimum care. In order that this may be
accomplished, the following recommendations should be
followed.
1. Keep excessive moisture and dirt out of air supply to
prevent wear.
2. Do not pound on the rear of the tool head to force
rivets into holes, as this will damage the tool.
3. Make sure the pulling head is correctly and securely
attached.
TROUBLESHOOTING
1. Air line pressure should be maintained at 90 to 120 psi at
the riveter. The air line should be equipped with a filter to
keep excessive moisture and dirt out of the air supply. This
will prevent clogging of the ports in the air valve spool and
sleeve.
2. All pulling head parts should be firmly attached. Loose
parts will affect the performance of the tool.
3. If riveter cycles slowly, the cause is usually insufficient air
pressure. Check it with the pressure gauge. It must be 90
to 120 psi. If air pressure is sufficient, the tool should be
cleaned out to remove any dirt which may be blocking the
air passages. Another cause of slow cycling could be lack
of lubricant on the O-rings. See the overhaul section.
4. Air exhaust is from the bottom of the handle. If air escapes
from the front or rear of the tool, the O-rings are either
worn or damaged and should be replaced.
5. If the tool appears to have excessive recoil motion, the air
pressure is probably too high. Check with a pressure
gauge, and if it is over 120 psi, it should be reduced. Too
much air pressure can adversely affect the O-rings.
OVERHAUL
The disassembly and re-assembly procedures can be accom-
plished by utilizing the following instructions and the drawings
on pages 6 and 7.
Use extreme care during disassembly
and re-assembly not to mar, nick or burr any smooth
AIR VALVE
•
To disassemble, first disconnect tool from its air source.
•
Remove the trigger (14) and retaining ring (16). Next, remove
Level-seal plug (19). The valve spool can then be pushed out,
from front to rear. The valve sleeve is pressed into the
housing and should not be removed. If ports in the sleeve
appear to be clogged, dip the handle in a solvent and blow air
into it to free any accumulation of oil and dirt.
•
Re-assembly of the air valve begins with new O-rings (17)
on the valve spool (18). Lubricate with a clear grease such
as Parker O-Lube, then insert into the handle of housing
6. If the tool does not set rivets correctly, the trouble may
be in the pulling head rather than the riveter. It may be
due to worn jaws or a weak jaw spring. See the pulling
head section.
Virtually all the moving parts in this tool ride on O-rings. This
means no metal to metal wear. By the use of close tolerances
and low micro-inch surfaces against which the O-rings seal, a
long life can be expected before any overhaul becomes nec-
essary. At that time, a complete overhaul can be achieved by
the use of Service Kits G780KS, which contains a complete set
of O-rings.
surface that comes in contact with O-rings.
Before
installing O-rings, be sure to apply an O-ring lubricant such as
Parker O-Lube to the surface.
from the rear. Use care not to damage O-rings by keeping
them centered. Push in as far as possible until the small
diameter of the valve spool comes out of the front.
•
Next, using Teflon tape or pipe joint compound on threads,
insert a Level-seal plug (19) and tighten firmly. The retaining
ring (16) is put into the groove of the small diameter of the
valve spool (18) and then the trigger (14) is put on the small
diameter of the valve spool and tightened with an allen
wrench on the set screw (15).
4
G780KS SERVICE KIT
QTY
PART NO.
ITEM
1 670B31
Rod,
Piston
3 P-293
O-Ring
1 P-507
O-Ring
2 P-508
O-Ring
1 P-534
O-Ring
1
TMAN GH-780
Parts List & Manual
