So my bro got this bt-4 combat for free from a game, and like a year after he won it we tried it and it failed pretty miserably. When we hooked up the C02 it pretty much froze the gun from an internal leak. Ive isolated the problem the the internals, leaking from what i beleive would have to be the bolt or somewhere close to it. I need help with this conundrum, if anyone has any input on the subject id love to hear it, cause right now im at a loss for what to do.
thanks guys!
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Bt - 4 Combat internals I need some help here guys
#2
Posted 24 March 2009 - 12:53 PM
I really doubt it is leaking from the "bolt"
Possibly broken powertube?
Possibly broken powertube?
#3
Posted 24 March 2009 - 08:56 PM
It is probably leaking from where the steel braided air line screws into the power tube. Try wrapping some of that white thread tape on the threads of the fitting and screw it back into the power tube.
#5
Posted 29 March 2009 - 06:48 AM
I have a BT ERC that did pretty much the same thing. When I took it all the way apart, I found that there was a small nick in the brass (I think it's brass anyway) part of the bolt, close to where the charging handle screws in. I took a dremel and a few sanding bits and smoothed it out, and no more problem. Also note that there were a few nicks on the inside where the burred bolt was starting to rub. I smoothed those out with a little bit of sandpaper.
All in all, was pretty weird considering that I had used the marker 10-15 times before this problem came up, and I never dropped it or hit it hard enough to really jar the internals. /shrug
All in all, was pretty weird considering that I had used the marker 10-15 times before this problem came up, and I never dropped it or hit it hard enough to really jar the internals. /shrug
#6
Posted 29 March 2009 - 09:02 AM
First make sure you oil and cock the marker before screwing in the tank. If it's leaking while the marker is cocked you definately have a problem.
If not it has to be the valve or where the steel braided line screws into the valve. The power tube only has pressure in it while the marker is being fired. Take the marker apart. The valve, power tube, steel braided line and the ASA will all come out in one piece still connected to each other. Once you have these parts seperated from the marker screw a tank into the ASA and pressurize the system. BE SURE TO WEAR YOUR GOGGLES AND HEAVY GLOVES WHILE DOING THIS. Check to see if the leak is coming from the where the steel braided line is attached to the valve.
Then remove the steel braided line from the valve and take the valve out of the power tube. While you have the valve out of the power tube go ahead and inspect the power tube for cracks. Now look into the hole where the steel braided line came out. Check that brass plug for damage. Sometimes the steel braided line will screw in too far and hit that brass plug. Then screw the steel briaded line back into the valve without the power tube. You will be able to see where the leak is coming from.
You may just need to replace an O-ring inside the valve or you might want to replace the whole valve. I would contact BT first as they may replace the valve under warranty. Good luck.
If not it has to be the valve or where the steel braided line screws into the valve. The power tube only has pressure in it while the marker is being fired. Take the marker apart. The valve, power tube, steel braided line and the ASA will all come out in one piece still connected to each other. Once you have these parts seperated from the marker screw a tank into the ASA and pressurize the system. BE SURE TO WEAR YOUR GOGGLES AND HEAVY GLOVES WHILE DOING THIS. Check to see if the leak is coming from the where the steel braided line is attached to the valve.
Then remove the steel braided line from the valve and take the valve out of the power tube. While you have the valve out of the power tube go ahead and inspect the power tube for cracks. Now look into the hole where the steel braided line came out. Check that brass plug for damage. Sometimes the steel braided line will screw in too far and hit that brass plug. Then screw the steel briaded line back into the valve without the power tube. You will be able to see where the leak is coming from.
You may just need to replace an O-ring inside the valve or you might want to replace the whole valve. I would contact BT first as they may replace the valve under warranty. Good luck.
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