View Full Version : Rocket Valve Problem

04-25-2007, 01:05 AM
I'm having a bit of trouble fine tuning one of my rocket valve setups. It seems I can't get it to recock consistently at pressures under 500psi. I'm using the Nightstriker XL, shim kit and a spring kit with it. Is anyone else using this particular combination? If you are, which combination are you using to get to the 300psi mark?

04-25-2007, 01:07 AM
what kind of bolt, regulator, and VA are you using? also, what main spring are you using? (i actually dont' like shim kits)
also, have you tried blocking off the exhaust port on the bottom of the gun?

04-25-2007, 01:14 AM
Reg: Evil Detonator
VA: Trinity 7*
Current Main Spring: Medium/hard
Shim: Normal (equiv. Stock)

I haven't tried blocking off the exhaust valve yet. I looked at where the striker placed itself and it didn't seem necessary. What can I safely block it with that isn't permanent but won't be so temporary that it'll fly out as soon as I gas up?

04-25-2007, 01:34 AM
you could use elmers glue. just makes sure it doesn't go into the body and just stays in the hole

04-25-2007, 02:37 AM
Elmer's glue? I don't have access to that brand. What kind of glue is it?

04-25-2007, 06:31 AM
If you don't have Elmer's, look for craft glue or something like it.

04-25-2007, 08:29 AM
My setup is in sig...I'm running 275fps @ 250psi.

make sure you have a high flow vertical adapter...and don't run the valve over 400 you will damage it.

Post your exact setup so we can help you. and take pics if you can.

04-25-2007, 09:55 AM
Try a lighter main spring.

Did you follow the directions to setting up the Rocket Valve?

04-25-2007, 11:33 AM
Thanks for the help everyone.

Critical - Craft glue? The 'kiddie safe' white PVA glue or the stronger, rubbery 'I'm a serious artist' stuff?

Strikefirst - Apart from the DH Titanium and BL Torp it looks like we've got almost the exact internal setup. I've got the same VA and valve (obviously) and I'm running the T-board. Are you still using the ACS bolt?

Shunut - I've followed the instructions on setting up the Rocket valve but I'm thinking of buying a rebuild kit just in case I've messed it up somehow. I'm gonna try using a lighter main spring as per advice from you here and others elsewhere and blocking the exhaust port with some blu-tack. Hopefully the blu-tack will hold until I sort out the glue thing. If that sorts the problem then I've just been going in the wrong direction with the springs...

04-25-2007, 11:41 AM
i think it might be your spring setup. the heavy spring might be too strong to run lower pressure's ya know? have you tried using the stock striker?

04-25-2007, 11:57 AM
I'm running the medium spring.

I was slightly higher psi with an acp bolt but under 300 now im running an alamo city bolt.

04-25-2007, 12:15 PM
I've just blocked the exhaust port and tried every spring in the kit and switching bolts and strikers. Same problem with every combination I've tried so far. I don't have a polished stock striker to try but that's why I bought aftermarket ones. I've got a DH Titanium, Nightstriker XL and a stock striker to hand so I've tried all 3. I've changed out the reg too between the BL Torp, Evil Detonator and Eclipse Star.

The parts I want/have to use:
ACS bolt
Eclipse Star reg
Nightstriker XL

I bought these parts specifically for this project so I'm reluctant to change my setup from the above. I think I'll have to take out the Rocket valve and check that everything is ok with it. I've used it at 500psi without much incident but I really wanted to drop lower, y'know, to where it's supposed to be. If it's messed up I'm gonna have to use a stock valve until I can order the rebuild kit. Any other ideas that I can try?

04-25-2007, 12:21 PM
hmm how much did you cut from the rocket valve's pin?

04-25-2007, 12:50 PM
From what I can remember I did it just enough to match the length of the stock valve as per Maddmann's site. I hadn't actually started tuning it in yet. I'll have to remove the valve to verify this because I got it when I was a complete and total noob so I might not have done it correctly.

Here's a pic of the valve alongside a stock one. I'd actually done it less than I was supposed to, much to my surprise (I'd done it almost 3 years ago!). Would shortening it make it work, d'you think? It should recock anyway, being that the dwell is longer, shouldn't it?


Just rereading the Maddmann page online after all these years (I'd just copied 'n pasted the info from 3 years ago) and it looks like I've got one of the older valves which is slightly longer. This means that the SRP doesn't have as much room to move which then means that it isn't staying open as long. This could be why I'm having recocking issues. I'm gonna have to buy a new one unless someone can give me any other ideas as how to fix this problem. I think modifying the blowback port is the last hope. What do you think?

Hob Hayward
04-25-2007, 02:50 PM
Get a rebuild kit and set the SRP out all the way for longest dwell, use a light main and try blocking the exhaust. (Of course also try w/o blocking exhaust, when I blocked mine velocity dropped wayyy too much, and it need high pressures to recock.)

04-30-2007, 12:39 PM
I'm not entirely sure what's going wrong now because I've switched out the rocket valve for another rocket valve that was working before and it still won't recock. Could the repeated stripping and rebuilding of my marker be damaging the o-rings on my strikers prematurely, causing a bad seal and losing the necessary pressure to recock?

04-30-2007, 01:22 PM
It should still recock, unless there was no seal at all and air was obviously blowing through the marker. I'm going to have to agree with your premise from earlier, if the SRP doesn't have enough room to move, it won't get enough air. You need to find a way to increase the dwell. If springs don't do it, it might be time for a board upgrade where you can adjust the dwell electronically. Or, try a stock valve/pin/spring and see if it recocks. If it does, it's something in the rocket valve setup.

Hob Hayward
04-30-2007, 01:24 PM
I wouldn't think so.

Did you block the exhaust port?

Also have you confirmed that the sear isn't worn and that the frame isn't loose?

05-02-2007, 06:45 AM
Get a rebuild kit. don't cut any of the valve stem off.

Block exhaust port.

The only other time i've seen this is when someone lost the spring guide and tried to run without it.

05-02-2007, 10:53 AM
Here's what I've done so far today on the 'newer' valve with no change to the results...

Changed out the valve stem for a long one then tried firing it
Blocked the exhaust port and tried again
Tried every spring I've got in my spares box
Tried out the last setup I had that worked (Spudnuk'l Nylatron Bolt, DH Titanium Striker and blue Maddmann spring)
Tried every spring again
Changed out the Star reg for a Torpedo
Tried every spring again
Tried a stock valve kit (Only burped at best because pressure was at 500psi)
Replaced all o-rings and tried everything as above again with both regs etc.
Unblocked the exhaust port and tried again
Put 'newer' Rocket Valve back in with original SRP (cut to original valve length as per instructions) and tried everything as above again

I'm completely lost and I'm thinking of giving up on the Rocket valve but I'm still determined to get it working. Another point is that I'm finding it difficult, as usual, to find somewhere that sells Spyder valves that also ships to the UK without charging a fortune. I really can't do anything else until I order a rebuild kit (or 2). :(

05-02-2007, 12:46 PM
have you removed the brass filter found in the stock asa?

if thats what you're using...

Your not changing the spring on the valve itself are you?

05-02-2007, 01:04 PM
I'm not using the stock ASA and I haven't thought about changing the spring on the Rocket valve. I don't have one that'd fit it. I really can't think of anything else that I've not tried yet. There's only 2 things I can definitely say I haven't done and they are...

Get a rebuild kit
Try a completely new Rocket valve