Hopefully divers will have stored their gun in a clean condition and with the muzzle pointed downwards over the non-diving season to keep the gun's internal oil supply lubricating the rear of the inner barrel sliding piston. However over a long storage period the oil film on the small diameter trigger transmission pin shaft and the power regulator control shaft will have dried out as they are both exposed to ambient conditions even if they are hidden from external view and you cannot directly observe them. To ensure that these parts are moved with lubricant on the "dry side" when the shafts are pushed through their operating seals when you first move them again it is worth pouring a few drops of oil into the power regulator control gate and down around the trigger where the back of it disappears into the grip near the trigger pivot pin. After allowing the oil to penetrate, carefully pull the trigger, it will feel stiff momentarily, then will immediately move freely as the now oiled pin slides in the trigger seal. Do the same with the power regulator, push the cursor knob forwards and down to "low power", then flick it up and the cursor should fly back to the "full power" position (the pressure in the gun blows it back).
Next put the gun into a muzzle up position and pour some oil into the muzzle relief ports and allow it to flow down into the inner barrel, you do not need much oil, so do not overdo it. Insert the spear into the muzzle and load the gun about half way down the inner barrel and then let the spear push back up again while keeping a steadying control with the loading bar while doing this. Don't be tempted to fully load the gun as this can be very dangerous on land! Repeat the exercise and then with the gun horizontal jerk the spear free of the piston to remove it from the gun. Those who have fitted dry barrel kits will have to pour some oil down into the muzzle opening instead, then insert the spear and press down with the loading bar until the piston moves away from the shock absorber face. The oil that you placed in the muzzle opening will run down into the inner barrel and then partial loading can occur as above in order to work the piston seals in the inner barrel once the oil has reached the outward facing seal surfaces. If there are no leaks then you are ready for the coming season of diving, however you might want to add some more air to your gun.
Before doing so crack the inlet valve to let some air out as this will clear the inlet valve of anything that may have lodged inside it by blowing it clear. Put a few drops of oil into the valve opening, connect up your hand pump and perform a few pump strokes into the gun. Stop and check for leaks, if there are any leaks the pump handle will be moved back as air pressure escapes through the inlet valve, then add as much air as you think necessary. Try loading the gun to ensure that you can budge the piston, but don't load the spear all the way, you should know by reaching the half-way point. If at the dive site you cannot load the gun put the power regulator on "low power" and then push in the inlet valve (with a blunt pin, use nothing sharp or you will scratch the inox ball of the inlet valve) and release a short burst of air. Lift the power regulator knob to allow it to move back and re-equalize air throughout the gun's chambers and then move the cursor knob back to "low power" to recommence loading activity. The use of the "low power" setting minimizes the air loss when cracking the inlet valve as the majority of the air is held in the forward air tank, you will be only bleeding down the air in the inner barrel and the pre-chamber behind the power regulator bulkhead. A brief burst of air makes a noticeable difference to loading effort, air comes out much quicker than you would think and you want to avoid dumping air that you may have to put back with the hand pump!
On a Scubapro "Magnum" pneumatic remember that "low power" and "high power" positions are reversed in the selector gate, it makes a difference, I have just been working on one!
Next put the gun into a muzzle up position and pour some oil into the muzzle relief ports and allow it to flow down into the inner barrel, you do not need much oil, so do not overdo it. Insert the spear into the muzzle and load the gun about half way down the inner barrel and then let the spear push back up again while keeping a steadying control with the loading bar while doing this. Don't be tempted to fully load the gun as this can be very dangerous on land! Repeat the exercise and then with the gun horizontal jerk the spear free of the piston to remove it from the gun. Those who have fitted dry barrel kits will have to pour some oil down into the muzzle opening instead, then insert the spear and press down with the loading bar until the piston moves away from the shock absorber face. The oil that you placed in the muzzle opening will run down into the inner barrel and then partial loading can occur as above in order to work the piston seals in the inner barrel once the oil has reached the outward facing seal surfaces. If there are no leaks then you are ready for the coming season of diving, however you might want to add some more air to your gun.
Before doing so crack the inlet valve to let some air out as this will clear the inlet valve of anything that may have lodged inside it by blowing it clear. Put a few drops of oil into the valve opening, connect up your hand pump and perform a few pump strokes into the gun. Stop and check for leaks, if there are any leaks the pump handle will be moved back as air pressure escapes through the inlet valve, then add as much air as you think necessary. Try loading the gun to ensure that you can budge the piston, but don't load the spear all the way, you should know by reaching the half-way point. If at the dive site you cannot load the gun put the power regulator on "low power" and then push in the inlet valve (with a blunt pin, use nothing sharp or you will scratch the inox ball of the inlet valve) and release a short burst of air. Lift the power regulator knob to allow it to move back and re-equalize air throughout the gun's chambers and then move the cursor knob back to "low power" to recommence loading activity. The use of the "low power" setting minimizes the air loss when cracking the inlet valve as the majority of the air is held in the forward air tank, you will be only bleeding down the air in the inner barrel and the pre-chamber behind the power regulator bulkhead. A brief burst of air makes a noticeable difference to loading effort, air comes out much quicker than you would think and you want to avoid dumping air that you may have to put back with the hand pump!
On a Scubapro "Magnum" pneumatic remember that "low power" and "high power" positions are reversed in the selector gate, it makes a difference, I have just been working on one!
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