Trouble shooting guide – Magnum Venus Plastech ATG chopper Gun User Manual
Page 23

ATC Chopper Gun Manual
Rev. 11/2012
Page | 23
Trouble Shooting Guide:
Air Assisted ‘AT’ Guns
Problem
Possible Causes
Recommended Solution
Air leaking from exhaust port on
back of handle while trigger is in
OFF position.
O-ring material worn or cut.
Replace O-rings.
O-rings on catalyst piston worn or
cut.
O-rings on trigger valve worn or cut.
Air leaking from exhaust port
on back of handle while trigger
is in OFF or ON position.
O-rings on trigger valve worn or cut.
Replace O-rings.
O-rings on Catalyst Valve and/or
Material Piston worn or nicked.
Catalyst leaking from catalyst
tip while gun is sitting, is not
being triggered.
O-rings on catalyst valve worn or cut. Replace O-rings.
Catalyst leaks from weep hole
on catalyst side of gun.
O-rings on catalyst valve worn or cut. Replace O-rings.
No catalyst is coming from
gun.
Catalyst air piston is not actuating.
Check for clogged catalyst air
passages (small holes
underneath back cylinder)
Note: There is more than one
passageway from holes.
Plugged catalyst restrictor (Allen
screw with orifice located in front of
catalyst valve).
Clean and clear orifice in front
of catalyst valve.
Plugged catalyst passageway in
head of gun or catalyst tips.
Inspect, clean and clear
passageways.
No catalyst flow to gun.
See “Slave Pump – Trouble
Shooting.”
Material is leaking from tip
(front of gun)
Loose diffuser seat.
Tighten diffuser seat ¼ to ½
turn at a time until snug and
then one more ¼ turn. Over
tightening of diffuser seat may
cause binding of material
needle.
Worn needle and/or seat.
Replace worn items.
O-ring on diffuser nicked or cut.
Replace O-ring.
Material leaking from weep
hole on material side of gun.
Loose diffuser seat.
Adjust until snug. Then turn ¼
to ½ turn more. Don’t over
tighten.
Worn needle packing.
Replace packing and adjust as
indicated above.