Leak Down Barrel

[Advanced]

UPDATE 1/18/10 3PM EST
The sear and bolt appear to be heavily worn, I think these may be the culprets, though I'm going to do a complete oring rebuild as well. Here are pictures:
http://i32.photobucket.com/albums/d7/chmodx/DSC08912.jpg
http://i32.photobucket.com/albums/d7/chmodx/DSC08913.jpg


Hi,

I've got an Automag RT (The original, not pro, not retro).

Upon airing up the marker, there is a loud gush of air down the barrel. The trigger does not charge, it's just straight air down the barrel.

Everything is stock.

Where should I start?

[secretweaponevan]

Hi,

I've got an Automag RT (The original, not pro, not retro).

Upon airing up the marker, there is a loud gush of air down the barrel. The trigger does not charge, it's just straight air down the barrel.

Everything is stock.

Where should I start?

You should start with Automag 101.

Pull and hold the trigger while gassing up.
If it leaks down the barrel, you have a leak in your on/off.

Release the trigger.
If it leaks down the barrel with the trigger at rest, you have a leak in your powertube.

[Advanced]

You should start with Automag 101.

Pull and hold the trigger while gassing up.
If it leaks down the barrel, you have a leak in your on/off.

Release the trigger.
If it leaks down the barrel with the trigger at rest, you have a leak in your powertube.

Ok, leak is when the trigger is held down. It almost sputters a little too, but mostly a heavy, consistent gush.

Onto the ON/OFF. Now what to look for?

[Advanced]

Ok, leak is when the trigger is held down. It almost sputters a little too, but mostly a heavy, consistent gush.

Onto the ON/OFF. Now what to look for?

Ok, I pulled the ON/OFF assembly out. I unscrewed the brass parts, everything looked ok. Gave a very, very slight moistening with oil.

Now, when I gas it up holding the trigger, it's silent. Upon releasing it, it leaks out the front.

On/off fixed, onto the power tube...

[Advanced]

Ok, I pulled the ON/OFF assembly out. I unscrewed the brass parts, everything looked ok. Gave a very, very slight moistening with oil.

Now, when I gas it up holding the trigger, it's silent. Upon releasing it, it leaks out the front.

On/off fixed, onto the power tube...

Still leaking, I give up.

[secretweaponevan]

Still leaking, I give up.
(I am assuming you have an original level 7 bolt)
Did it work before?

If so, replace the powertube o-ring.

If you have a spring in the powertube is is more than likely worn out and should be replaced by a spacer kit available from Tunaman (http://www.tunamart.com) or AGD. If you do have a spacer in the powertube and you still have the powertube leak after you replace the o-ring you should move to a smaller spacer.

Since your on/off top teflon o-ring did the "lawn sprinkler", you should replace it before it totally gives up the ghost mid-game.

[Advanced]

(I am assuming you have an original level 7 bolt)
Did it work before?

If so, replace the powertube o-ring.

If you have a spring in the powertube is is more than likely worn out and should be replaced by a spacer kit available from Tunaman (http://www.tunamart.com) or AGD. If you do have a spacer in the powertube and you still have the powertube leak after you replace the o-ring you should move to a smaller spacer.

Since your on/off top teflon o-ring did the "lawn sprinkler", you should replace it before it totally gives up the ghost mid-game.

Power tube has a spacer in it, an oring behind it(no spring). I'm going to just buy an RT parts kit and replace everything. I think that should fix my problems.

Hopefully the paintball store will be open tomorrow with the holiday, otherwise I'm going to order it online since I won't have time during the work week.

[kcombs9]

not many local pro shops still carry agd parts kits but if they do count your self lucky ;)

[Ando]

Tuna will be open tomorrow :p

He ships out very fast.

[Advanced]

Tuna will be open tomorrow :p

He ships out very fast.

I noticed one more thing....hopefully this helps to narrow down my problem further.

The bolt seems to be staying back, but if I push it back a little further with a wooden spoon, the leak stops. It appears the bolt is not staying back quite as far as it needs to.

Solutions?

[Ando]

Replace your spring ;)

[athomas]

If the trigger is coming forward then it is not the bolt spring. If the spacer is too long, it holds the oring too far back. When at rest the bolt stem never contacts the oring. By installing a shorter spacer, it allows the oring to come forward and seal against the back of the bolt stem. The change in sealing ability is often due to wear on the sear which then allows the bolt to sit farther forward than when new.

[secretweaponevan]

Also check to ensure that your rail bushing is in place.

Without it, the valve will sit a tiny bit back farther, while the bolt will stay in the same position by the sear. This could cause a powertube leak as well.

Here is a picture of one protruding from the rear of the rail behind the sear.
http://www.pentestone.com/paintball/PumpMag/PumpMag%20021.jpg

[Advanced]

Also check to ensure that your rail bushing is in place.

Without it, the valve will sit a tiny bit back farther, while the bolt will stay in the same position by the sear. This could cause a powertube leak as well.

Here is a picture of one protruding from the rear of the rail behind the sear.
http://www.pentestone.com/paintball/PumpMag/PumpMag%20021.jpg

I have an RT classic, no rail bushing because of the banjo.

Does the RT classic use the same sear as the classic?

[Advanced]

I have an RT classic, no rail bushing because of the banjo.

Does the RT classic use the same sear as the classic?

Updated main post, see first thread for new pictures.

[xero28]

I'd say the bolt/sear are most likely the culprits. If the bolt isn't held snug up against the power tube o-ring, it will vent down the barrel. Because of the wear, I would suppose that the bolt is being pushed forward a bit and is not able to sit up snug next to the o-ring. I read in one of your posts that if you push on the bolt, the leak stops, correct? If so, then yes, get a new bolt and a new sear and you should be good to go. Make sure you get an RT sear though, as they are not interchangeable with a standard AutoMag/MiniMag Sear.

:cheers:

[secretweaponevan]

I have an RT classic, no rail bushing because of the banjo.

Does the RT classic use the same sear as the classic?

Dur. I thought of the missing bushing right before I drifted to sleep last night. I didn't re-read all the particulars before posting this morning.

Yeah, you need a new bolt and sear.

[athomas]

Looking at those sear and bolt pictures, I have to say they are most likely the culprits. Those are about the worst I have seen.

[Advanced]

Looking at those sear and bolt pictures, I have to say they are most likely the culprits. Those are about the worst I have seen.

Yeah, I was really surprised, it's chipped like that completely around the bolt edge. The sear is pretty messed up but the bolt appears worse.

This is actually good timing...I alsot bought a minimag last week. I also bought a ReTro valve + level 10 from someone else. Both will be arriving in the next 2 days. Once I put the retro into the mini, I'll drop the level 7 bolt into this one temporarily. Now all I have to do is order a new sear and the parts kit.

I'll put a lev 10 in this RT next paycheck.

[Ando]

Don't toss the lvl 10 just yet, might be salvageable. The sear on the other hand is Tango Uniform. That's the worst sear I've seen for sure. I've seen worst bolts still work though, hopefully it can be reused.

[athomas]

No, that bolt is toast. It might work for a while with a new sear, but it wouldn't be advisable. With the rounded edge, the tip of even a new sear would have the tendency to slip off and release the bolt. This would cause excess wear on a new sear and it would soon look like the one that is there now.

[Advanced]

No, that bolt is toast. It might work for a while with a new sear, but it wouldn't be advisable. With the rounded edge, the tip of even a new sear would have the tendency to slip off and release the bolt. This would cause excess wear on a new sear and it would soon look like the one that is there now.

This is a level 7 bolt right now. I'm just swapping the one from my minimag onto it in the mean time. I'm going to just replace both and have a fresh start on life with it.

The bolt edge is really jagged to the finger touch. I think putting a clean sear to it would just tear up a new sear and let it slip here and there.

[Ando]

The bolt edge is really jagged to the finger touch. I think putting a clean sear to it would just tear up a new sear and let it slip here and there.
That's what they make files for ;)

Trust me. I've filed a few bolts in my time. It'll be fine. Send it my way and I'll recondition it, test it and if it isn't to far gone i'll send it back.

Next to a CNC machine which I wish they had in that shop (in another building). I can do just about anything. I could also give it to one of my boys there and he'll have that thing looking as good as new. Just pay the shipping back and forth and we'll call it good.

PM me if your interested.

[Adam45]

I would disassemble everything and clean out any metal shavings that are inside. They will cause unusual wear and create problems hard to diagnose later.

I recently repaired a friends RT that had a bolt and sear with much the same wear. Your best to start with a new bolt and sear, theres to much tinkering to fix the ones you have.

[Advanced]

I would disassemble everything and clean out any metal shavings that are inside. They will cause unusual wear and create problems hard to diagnose later.

I recently repaired a friends RT that had a bolt and sear with much the same wear. Your best to start with a new bolt and sear, theres to much tinkering to fix the ones you have.

I replaced most of the orings in the gun, replaced the sear, and the bolt.

Works fine now, when I put the bolts side by side, I'd say the original bolt was worn down by more than 1mm. I also noticed the springs, the new one was about 5-6mm longer when at rest, possibly indicating why the bolt was able to be pushed back.

The orings inside the gun were all the dark brown, probably the original factory ones from many years ago. All the new ones are the white ones.

Thank you all for your help.

[athomas]

Glad to hear you got it repaired. :clap: