3 replies to this topic

[Banshee]

I've been messing with this one for a few weeks now and I'm stumped. I bought it at a thrift store, and I was pretty thrilled about it, but later I found that it doesn't hold pressure. You pump it up and it leaks right out of the barrel end of the tank. I opened it up and put it under water, and it leaks from the front of the tank and nowhere else. The check valve is fine, the hole for the firing pin is fine, its just the rubber seal in the tank that leaks. I was really disappointed because the only way to get to the seal was to cut the barrel off. And that means the gun will never be in original condition which is what I wanted, but I'd rather have a working modded gun than a broken stock gun, so I cut the barrel off.

Once I could get to the seal, I used a little oil on it, that didn't do anything. So then I put a little lithium grease on it. That helped a tiny bit, but it still wont hold pressure. Its not an instant leak, I'd say it takes about a second to leak out 2 pumps. When I push the firing pin into the tank and pump it, it makes no difference, so I don't think a stronger spring would fix it. It seems that higher pressure seems to help seal it, so plugging the pump might work, but not only is the pump glued in and I can't get it out, but I hear that plugging the pump on a SM500 can blow the tank, so I really don't know what to do. I would like to be able to soften the glue on the tank and open it up. I don't want to cut it because I've never been able to successfully glue tanks back together, and since this tank is attached to the pump as one big piece, I'm not even going to try.

I've done everything I know how to do to fix this thing, and I haven't gotten very far. Does anyone have any ideas on what I could do?

[SpokkyLucaz]

I have been having this EXACT same issue, just on a different blaster(SM750). I have tried everything short of opening the tank and fiddling around...I hope you find an answer to this.

[roboman]

Well, if you haven't already, I'd suggest holding the valve open and blowing some compressed air in with an air compressor or one of those "canned air" things. It might be as simple as a piece of debris on the front wall of the tank or on the rubber itself.

[hamoidar]

Although I have never worked with a sm500, I had a similar problem with my sm3k. I don't know if you problem is the same as mine, but I did find a way to remove the top of the tank without cutting anything. I used a micro torch with a heat-gun attachment to heat the edge of the tank "lid". Once it was pretty hot, and the glue melted, I used a screw- driver to push the lid off. Once I had fixed the problem, I used a combination of PVC cement and JB weld to secure the tank lid back on. Hope this helps!