X-valve ULT issue

[cerrik]

A friend of mine picked up an X-valve with ULT from EBay. And it doesn't work... Big shocker there. I am servicing it since he knows nothing about automags outside of what I tell him about them.

I'm totally new to X-valves and ULTs.

The X worked when I aired it up initally but it short stroked and chuffed on about every 3rd-4th pull. I took apart the X and checked it out and everything looked kosh. Then I started working on the ULT and reading up on here about them. So I added and shim and then from there, everything went downhill. Now, the gun doesn't even fire. With 0 shims all the way up to 6 shims.

I'm at a loss here and it's a shame to think that I'm now holding a larg hunk of useless aluminum when I know much better about Automags. Will anyone help? Please.

[athomas]

Make sure the air source is a high enough output. Make sure the level 10 is functioning. Turn up the velocity.

[Spider-TW]

Used x-valves are hard to guess at. First thing like athomas said, is to make sure you turn the velocity up to some sensible level (sound / feel initially if possible). Next would be to make sure the level 10 bolt doesn't feel too tight. The bolt should have the largest carrier that will hang the bolt (over something soft ), skip (take out) the shims for now. Make sure the bolt spring is around 1/8" to 1/4" past the tip of the bolt.

Take the top off of the ULT and put some oil on the shaft above the micro oring in there and work the oil into the seal, so that it moves smooth. Put a little on the top oring while it's out.

The reg piston is basically the same maintenance as the classic. Take it out and clean the piston, oring and inside of the reg. relube and check that it slides evenly in the reg body.

To remove the reg pin, you need to carefully pick the top oring out. It looks like it is loose in there, but it hits the shoulder of the cavity when you try to pull the pin out. Pay attention to the location of the brass reg seat-spacer [?] and don't loose it. If you can pull the reg pin out with your fingers, it is probably fine. If you have to stick something soft in the hole of the pin to pull it out, clean the pin and the cavity and relube. There is a plastic washer on the reg pin that is basically a split washer (FYI), it's not cracked.

As long as the orings aren't brown or leaking, a good cleaning should get it working at least in semi-auto. Some oils get gummy and good ones still don't penetrate everywhere even though they end up shooting out the bolt. With a gummy valve, you have to work that stuff out of it.

[Dend78]

if it were me i would say get ahold of a regular on/off tune your level 10 first, then once its smooth then add in the ULT and tune it. this will save time and eliminate some problems that will come from trying to tune both at the same time. think of it like a guitar with a tremlo system, you tune one string at a time and once your done with them all go back and double check the first one cause the loosening and tightining on the tremlo threw the other strings off a bit

[cerrik]

Yeah I took the approach of using a regular Rt On/Off since I've had one for sometime in my Minimag valve. I'm loathe to tear down the LX due to the fact that it only stopped working once I started fiddling with the ULT.
That and I can't tweak the LX other than with the shims. This thing was picked up on ebay. So I have the X with the red spring and only the carrier that is in it now plus a parts kit with xtra orings and shims. And ULT shims as well.

Now, with the RT on/off, it rapid fires and ounces like mad off my finger which is impressive enough but, once I try to pull fully for a semi auto shot, it gets bolt stick and air leaks out the barrel until I release the trigger again.

If I have to, I'll just tell him to pick up a carrier set from AGD and start from scratch.

[Spider-TW]

Sounds like too many shims or leaky top on/off oring if it is leaking with the trigger down.

[cerrik]

Good god I hope it's not a leaky on/off top o-ring since the On/off works great in my minimag.

I told him to pick up a complete carrier set so I can work on tuning the LX from scratch before moving on to his ULT. But in the mean time, I'll start messing with shims.

[Spider-TW]

Check that the parts that are in the level 10 are in there in the right order and all present. I recently got one where there were shims under the carrier, instead of on top. I've heard of the backing washer being missing as well. I expect someday to see a carrier without the black oring, since they pack them un-assembled.