This page describes how to disassemble, clean, and reassemble the Impulse. It is said that you should re-grease your marker after every day of play. Personally I agree and always do this. This will ensure that it not only functions good, but it will also make sure that no parts of the marker will be damaged from not being used for periods of time between your games. To help you to clean your marker, you should have at least two lint-free cloths nearby (or equal substitute). You will use one to clean with and the other to set parts on. I suppose paper towels or napkins can suffice too, but a cloth is best. And I'm sure that I don't have to remind you to use DOW Corning 33 Shocker Lube with your equipment when it's needed. Of course you're going de-gas any marker before you disassemble it.
These are the things you'll need for a complete overhaul of your Impulse: assorted allen wrenches, Shocker lube, flat-head screw driver (2001 and earlier), Q-tips, napkins/paper towel/cloth, 7/8" wrench (or a pair of pliers can be used), needle-nose pliers, cleansing alcohol.
Disassembly:
A complete disassembly of the marker is not required, however that is what I will describe on this page. First, field-strip the body by removing the bolt pin from the top, then allow the bolt to slide out the back.
Once it's the bolt is out, use your pliers or 7/8" wrench to unscrew the hammer piston from the rear of the body (the lower bore). Don't use an allen wrench (or screw driver if 2000-2001) to remove the plug in the rear of the housing; you need to remove the entire housing. Once the threads disengage, pull it straight out the rear of the body.
You can then unscrew the front endcap from the body (under the barrel). Depending on the valve used in the gun, there may be a spring within the air chamber at the front of the body. Pictured here is the stock endcap from a 2004+ Impulse. Previous models used a cylindrical endcap that would also fir a 7/8" wrench or large pliers.
Now it is time to separate the circuit housing from the body. Do this by unscrewing the two screws in front of and behind the frame, using a 1/8" allen wrench. Pull the two apart. if you have a non-Vision Impulse, you will have to unplug the solenoid from the circuit board. If you have a Vision Impulse, however, tou don't have to do this.
You can then use an allen wrench to remove the valve lock screw from the underside of the body. Once it's out, use the handle of a wooden spoon (or similar device) to push the valve housing out the back of the body. Don't push it out the front.
Maintenance:
Maintenance for the hammer piston involves further disassembly. For this, you must unscrew the endcap from the rear of the piston using a 3/16" allen wrench (or flat head screwdriver if 2000-2001). Then, grasp the hammer in one hand while inserting a 1/8" allen wrench (or screwdriver if 2000-2001) into the head of the piston exposed within the rear of the housing. Unscrew one from the other to remove the hammer from the ram. You may need to use a heat source (such as a hairdryer) to loosen the hammer from the ram.
Once the hammer is off, push the ram out through the piston housing (use a pair of needle-nose pliers to pull it out if needed). Note that the stock piston involves two separate bumpers around the ram: the open bumper on the outside (next to the hammer) and the close bumper on the inside (next to the head of the ram). The close bumper often times stays inside the piston when you remove the ram from it (becuase of the grease) so it's okay if it doesn't come out.
Clean the inside of the housing using q-tips (or whatever else), and also clean the forward o-ring in the front of the piston housing (below) as well as the o-ring around the head of the ram (above).
For the valve, you will be able to push the valve plunger (aka. cupseal) out the front of the valve housing. Certain aftermarket valves have internal retension springs which will have to be overcome, however it is not too different from the stock valve. Either way, once the plunger is out you can clean the o-rings as well as the inside of the housing, and the o-rings on the outside of the housing as well. It is important to keep the plunger and the opposing surface of the valve housing clean to prevent leaks down the barrel. Alternately, be sure not to leave any small hairs in there when you do clean it.
The o-rings around the housing will cause leaks if damaged, which would of course warrant replacement.
If you're using the stock (aluminum) bolt, you should also clean the o-rings around it. You can grease the rear two o-rings however not the one in front.
Reassembly:
If you disassembled the piston, you must now reassemble it. Apply a coat of grease around the piston o-ring then push it back down through the back of the piston. Be sure the close movement bumper is installed on the ram. Once you push it through, insert your 1/8" allen wrench (or screwdriver if 2000-2001) into the head of the piston and apply a small coat of thread locker to the threads on the opposite end, then screw the hammer back onto it. Re-grease the o-rings around the piston housing then screw it back into the Impulse body. Overgreasing these three o-rings will work fine.
Re-grease the o-ring around the valve plunger then reinstall it into the valve housing. A light coat of grease is all you need. Then, re-grease the o-rings around the housing (again, impossible to overgrease) and insert it back down into the back of the Impulse body. With the stock valve, it does not matter which of the ports (top or bottom) faces which direction; they are the same. Some aftermarket valves are not the same, though. Once you reinstall it into position, reinstall the valve lock screw as well, after regreasing the o-ring around the end of it. This o-ring is also impossible to overgrease.
You can reinsert the bolt into the body then drop the bolt pin back into position. If you are using the stock bolt, be sure to re-grease all but the front o-ring.
Every six months or so you should also clean out your filter with alcohol. The filter can be found in the main gas distribution manifold that runs the entire length of the body. Remove the plug then tip the gun on its end so that the filter slides out, then clear it free of debris.
The vertical adapter also houses an o-ring to seal against the body. If your adapter leaks from that location then it may be time to replace it.
O-ring Diagrams:
Solenoid Maintenance (note: this link will take you to the Shocker Sport solenoid page; the same maintenance proceedure is used for the Impulse)