BSA Sportsman HV diagnosis....?

[xschug3]

I took a shot and immediately after the shot, all the air 'wooshed' out of the barrel. I'm just trying to diagnose the problem at this point. I tried pumping the gun back up with my FX pump and it wouldn't take any air. It seems that the valve is stuck open or something....?

Has anyone had this happen to them with any of their pcp guns? Is this a common problem with BSA guns?
Please help! The starlings and crows will be coming in soon and I need this gun full of air!

[rkr]

Sounds like some debris found it's way to the firing valve and keeps it open. Here's a guide for taking it apart for inspection http://bsaog.co.uk/forum/index.php?topic=5172.0 Just make sure the gun is empty of air before you start. Unless of course you shot it too low on pressure and the hammer spring is keeping the valve open? That can be fixed by pumping up the gun when the hammer is cocked.

[SAADE]

Is the gun a new, recent purchase?

I would check your warranty fine print. Almost always, if you dismantle, warranty is void. Better to send it back if it's a recent purchase.

[rsterne]

Try cocking the gun before pumping.... If that doesn't work you have some debris in the valve and it will have to be disassembled to clean it....

Bob

[xschug3]

Thanks guys. The gun is not new. I purchased it used from someone ~2wks ago. Until now it's been an AWESOME gun and I've had no issues at all. I've always cocked the gun before pumping it up with my FX pump, as I read that makes it easier to pump.

I'm guessing the valve is stuck open, but how do I get to the valve and where is it? I pulled the cylinder off already. This is my first pcp and I'm not familiar with the terminology.
I'm just hoping it's something as simple as debris in the valve, but I wouldn't even know how to check that. Can someone give me some more details?

RKR- the information you posted seemed to be more in depth than maybe necesarry....(I think).
Thanks for the help

[rkr]

You could remove the airtube (it should screw off when pressure is released - I haven't tried that, yet) and see if you can remove debris from that end.

[xschug3]

Ok! It looks like I fixed it! It's accepting air now! PHEW! Nothing major after all.
I unscrewed the cylinder, unscrewed the brass cap with 4 holes in it (knockoff retainer cap), removed the "choker" or knockoff restrictor 282 , valve stem spring, and knockoff valve. I used the exploded diagram on the bsauk website.
I pulled them all apart and checked everything to confirm nothing was damaged or cracked or dirty. It all checked out okay. I then used dielectric grease and relubed everything and reassembled. Tightened the cylinder back down and began pumping! I put the action back in the stock and have taken a couple shots and the air has held in the cylinder. I'm guessing it was just debris in the valve.
Thanks for the help guys!! Now.....back to pumping. Uggh. I've never had to start from a completely empty cylinder. This is work. Lol

[rkr]

Good you got it sorted out. Try to keep the probe and fill port clean to avoid any future mishaps. It's usually a piece of dirt or nicked o-ring that's causing the problem, easy enough to fix. In worst case something may have nicked the valve seal and that usually takes more effort or spare parts to fix.

[TKO22]

We spoke on the phone and after disassembling, lubing and reassembly, it didn't seal up.

Did you do something else after we talked to get it to seal?

MIke T.
TKO - Omaha, NE USA
www.tko22.com

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[xschug3]

Hey Mike! I actually disassembled the gun again a second time per your instructions. I did nothing different the second time, I just made sure that everything was reassembled properly and seated like it should be.
I honestly think there was just debris in the there.

Thanks a ton for your help Mike! I appreciate you taking the time to walk me through the disassembly. I'm so glad it was nothing serious.

[xschug3]

The one thing I'm noticing now is a little air seeping out of the brass fill port. I can hear it slowly seeping out.
Do you know what would cause this or why all of a sudden air is seeping out?

[rkr]

The one thing I'm noticing now is a little air seeping out of the brass fill port. I can hear it slowly seeping out.
Do you know what would cause this or why all of a sudden air is seeping out?

Debris or blown o-ring in the fill valve. Similar procedure for the other end of the tube. Before you take it apart and fix I'd take a serious look of your filling setup. That debris is coming in from somewhere and it sounds like your pump or bottle has some gunk in it. While you are at it check the air tube for cleanness also.

[xschug3]

Thanks rkr. Using the pump doesn't make for the cleanest filling process. The probe from the pump is constantly laying on the carpet and the gun is on the carpet as well. I don't fill up outside or in the garage, only in my house. But I'm not sure there's any way to make things cleaner..... ?
Should I use a can of compressed air to shoot on the probe and port before filling or something?

[rkr]

Thanks rkr. Using the pump doesn't make for the cleanest filling process. The probe from the pump is constantly laying on the carpet and the gun is on the carpet as well. I don't fill up outside or in the garage, only in my house. But I'm not sure there's any way to make things cleaner..... ?
Should I use a can of compressed air to shoot on the probe and port before filling or something?

One piece of carpet hair in wrong place is enough to cause a leak, try having a clean environment in where you pump. Blowing things clear with compressed air won't hurt and you could do that to the fill hose as well (after removing it of course). If yours is a well used pump it may be in need of rebuild as gunk tends to build up due to moisture and too long pumping periods and it may find it's way to the airtube. BSA pumps are made by Hill so you can get rebuild kits easily.

[xschug3]

Thanks rkr. I have a dog and he's a shedder. I wouldn't be surprised if a stray hair found its way in the probe or port.
Thanks for the help.