Big leak down barrel, trigger pull causes RT - Classic valve no R/T on/off

[ChristianFromPitt]

So i was playimg today, ball gets stuck on a break in the hopper, big gush down the barrel. I di a full clean amd rebuild, still major leak down barrel. Then i take apart my poeer tube, check my o-rings, no tears, all in place (does a small o-ring go down the bottom of the power tube assembly on a classic valve?)

Now i air up, still the big gush down barrel, but the gun R/T's when the trigger is pulled. I take out the on/off, clean and reassemble but the problem is still there upon reassembly.


Any ideas?

[blackdeath1k]

Yes there is a small Oring in the power tube. Sounds like your problem if the leak stops when you hold the trigger in.

[ChristianFromPitt]

When i pull the trigger, it r/t's even though its not a r/t valve.

[blackdeath1k]

Bolt or sear worn out? That would cause leaks down the barrel and rt effect without an rt valve.

[athomas]

First thing you need to do is diagnose where the problem lies.

If you hold the trigger in all the way, does the leak stop or does it sputter? If holding the trigger stops the leak, then your issue is the powertube area. Most likely, your powertube oring or perhaps your spacer is too long. The spacer issue could rear its ugly head if your sear is worn a bit and then got suddenly very slippery with paintball gunk.

If the leak doesn't stop when you hold the trigger, and just sputters, then you have a leak in your on-off area. That would most likely be small inner white teflon oring on your on-off top.

[OneSelfLost]

Bolt or sear worn out? That would cause leaks down the barrel and rt effect without an rt valve.

I had a chipped sear recently which gave these exact results. Very frustrating to diagnose because it's typically not the first place you'd look. Take the sear out and look at it real close.. I had to hold another sear up to it just to compare, it was hard to see.

[ChristianFromPitt]

So I have a classic valve and would like to get a 3x rebuild kit for the powertube and on/off for $20 or less.

I've rebuilt it and stopped the RT effect and the leak continues but stops when the trigger is pulled. Its been 2 years since the o-rings have been replaced on the mag.

If you have the o-rings and want to sell them, PM me. Or post a member I can PM. I know of tunaman but am willing to compensate a former if yinz can help me out.

[OneSelfLost]

Everything oiled, tried new spring? .. Try turning the velocity down all the way, and then back up until it cycles again, then go half a turn past that. Wait.. does it cycle? Or does it just leak and go silent when the trigger is pulled?

Also, have you tried adjusting how tight the front body screw and the thumb screw are?

[athomas]

A leak down the powertube that stops when you hold the trigger is either a bad powertube oring or a powertube spacer that is too long. If you have already replaced the powertube oring, I would say your powertube spacer is too long. This is probably a symptom of a sear that is wearing. As the sear wears, the bolt sits farther forward and the bolt stem no longer seals against the oring. Using a shorter powertube spacer allows the powertube oring to stay in contact with the back of the bolt stem even with the bolt sitting farther forward. The powertube spacer is an adjuster for the powertube oring.

[ChristianFromPitt]

I did not replace any o-rings, just a cleaning. I dont have the right o-rings to replace on the mag.

The mag R/T's when the trigger is pulled down. I figure replace the power tube o-rings and on/off o-rings.

[athomas]

A complete clean and rebuild means replacing all the orings, so I was under the impression they had been changed.

You should try the new powertube orings then. That should fix your leak out the front. Like I mentioned before, if the oring doesn't fix it, then you will need a shorter powertube spacer.

You indicated in post number 7 that the RT effect has stopped. That is a good sign. If it returns or still causes random reactiveness, then I would still replace the on-off orings.

You should also replace the regulator seat. Any time the valve halves are taken apart, that reg seat oring never lines up the indentations that are created in it and it generally causes hot shots and/or overpressure venting out the back.

A complete kit is the best way to get all the orings you need and will give you a few extra. Its the ones you don't think you need and are missing that are the most annoying if they fail.

[blackdeath1k]

I did not replace any o-rings, just a cleaning. I dont have the right o-rings to replace on the mag.

The mag R/T's when the trigger is pulled down. I figure replace the power tube o-rings and on/off o-rings.

I suspect the complete clean and rebuild comment had everyone assuming new Orings and problem still exists. If the marker hasn't had new Orings in a long time give it a full set of new rubber before you bother with anything else.