View Full Version : air leak problem with LP spyder

05-28-2008, 08:23 PM
Before I start, here is my set up:
Stock ACS bolt
32* Magnaport Valve and pin
maddog valve kit
Dark Horizon Titanium striker
Rocking trigger (which I set to only work as a single trigger)
CP regulator (set at 300psi)
Trinity front block.
All running on HPA
Freak and Empire barrel kits

Ive been working on taking my spyder pilot to LP. Just put my last piece for it in, a Dark Horizon Titanium Striker.
The problem I'm having is, after shooting about 200-300 rounds, it starts leaking really bad. I've put a heavy valve spring in, but when I put a medium main spring , the sound of it firing is like it's double fire, but it's not missing the striker. Best way to describe it is "belerp". Seem it's double tapping the valve pin before coming back to the searer. I switch back to the light spring, but my velocity will only goto 225-230.
I'm thinking I need a new cup seal but I don't know if they sell just the plastic ring for the valve pin.
The other thing that has started happening is if i fire somewhat fast (about 13bps) it breaks a ball. I have changed the barrel size and made sure the barrels were clean and snug to the gun but it will still break about 15 balls into the cycle.. This would be with the medium valve and light main. The of coarse the air leaking will happen. I've put lock tite on the valve pin since I did have that come loose in the gun once.
If anyone has any ideas that can help alleviate this, it would be great. If you need any more information, please feel free to ask!
Thanks in advance!

05-28-2008, 08:27 PM
Sounds like a bad cupseal.

05-28-2008, 08:36 PM
That is my first thought. Tried to use the cup seal from the stock but wont fit the pin. Threads on the magna port valve are a bit longer than the stock. Anyone know where I might find the small plastic/delrin disk at?

05-28-2008, 10:09 PM

Click products, then Kingman. It's at the bottom.

05-29-2008, 02:25 AM
What pressure are you running at?
I had some funny things happen with my LP project so just hang in there and you'll get it all ironed out. One thing that helped me was to air up the gun, increase the reg pressure to about 600, and let it sit over night with the pressure pushing the cup seal aginst the valve. I have the Alamo high flow cupseal and it is more rounded than the stock unit so I had some sealing/seating issues. I also polished the lip of my valve body (where the seal seats) with a dremmel and cloth-plug buffing attachment using polishing compound. As for the springs and achieving velocity; try the medium or light valve spring and shim behind whatever main spring you use with a washer or two. I finally ended up with a light valve spring, a medium main spring, and a small plastic shim (about 1/4" thick) between the main spring and velocity adjustment screw. It's all just trial and error. I also can't say enough about the Bandit LP bolt. It solved a lot of tuning issues for me.
Good luck.

05-31-2008, 07:11 PM
mine did that before but i put my bellbody backwards i dunno if thats whats rong with urs

06-01-2008, 06:56 AM
Well I was able to get the valve pin on the 32* valve to fit in a stock cupseal and i think that is working. Will put it under heavy test today. I have the light valve spring with a stock main spring but my velocity wont stay above 255. So I put the stock striker back in and now it's up to 275 max. Tried to use the heavy main spring but it wont recock even with the reg at max. so I'm stuck with the stock/medium. Going to buy a shim kit later and see it that helps. Thanks for all the help here! Any other suggestions on anything, please let me know!

06-01-2008, 03:52 PM
What reg pressures are you running at? What type asa are you using? If you have the stock asa and haven't modded the port, you may be starving for airflow. Check otter's site; there's a section on drilling the air port hole in the asa. *Be forewarned- you can damage it if not careful*
Good luck and keep us posted.

06-01-2008, 08:02 PM
Just had it out today. Worked great. It's operating at 300psi +/- a few. For some reason, I was able to get the velocity up to 280ish. Only thing I did different was turned the regulator all the way off, attached the air tank, then brought the pressure up to 300. Maybe before the reg didn't like being aired up while open. I think a shim kit will help bring the velocity up a bit more, since I really don't like having the adjustment screw all the way in.
Going to put my titanium striker back in and see what happens. hopefully the velocity will stay up. Will be nice with less kick.
I'm using a psychobalistic bullet ASA. It's open pretty well. Know of any others that would be great? I have an adapter so I could use a asa that the screws are aligned instead of offset.
To bed I go!

06-02-2008, 11:25 AM
How old is that reg? Maybe you just need to put a few cases of paint through it before it settles in and you fine tune it. If it's new there's a break in period. keep it lubed up well. Good luck.

06-06-2008, 09:31 PM
Ive had about 2 1/2 cases or so through it. Will paintball gun oil through the asa be good enough to lube it? I have the light spring on the valve right now and a medium on the main. I've tried the heavy on the main but it starts acting funny. It seems to double tap the valve pin before resetting on the searer. It's pretty fine for now. Once I get a shim kit, I'll be able to back it out a bit. The velocity is sitting between 275 and 285 with the stock striker. I'll play around with the titanium a little later.

06-07-2008, 09:51 AM
I'd say you are where you need to be. Chances are you are chronoing on a first or single shot. I'd be willing to wager that if you chrono'ed on a chrono like mine,


which reads multiple bursts and gives a minimum and maximum velocity out of the radared burst, you would find that you might have a maximum velocity over 300 fps out of a set of volleys. Conversely, you may find a minimum under 250 fps. What does it all mean? You are probably in the sweet spot zone with tuning and given the fact that it's a percussion marker, are all set to rock n' roll.