RT Classic reg piston and Reg seat questions

[sdn137]

I have a couple regulator questions:

1) While taking apart my RT i was unable to remove the regulator piston assembly without unscrewing the tiny allen set screw on the outside of the regulator housing. I thought this set screw was only to lock the valve into the Z - slot, does it do anything else? should it be so tight that it touches the regulator piston?

2) In the video that came with the gun, the regulator seat appears to set down into a recessed area tight enough to stay on the regulator body. Mine does not do that, it will fall right out. The other side, the o-ring side, does fit tightly around the regulator valve pin, though. Is anything wrong with mine, or just a slightly different model?

Here are some pictures. Thanks in advance for any help!

[Tunaman]

Apparently, the zlock pin has been changed to a set screw. If someone drilled it out too far and had to put a screw in there it would be possible to hit the reg piston if screwed in to far. Install the regulator valve pin all the way in. If it sticks out too far the reg seat oring will not seat in the groove. If you can get it down in there and it is loose then change the oring.

[Spider-TW]

Apparently, the zlock pin has been changed to a set screw. If someone drilled it out too far and had to put a screw in there it would be possible to hit the reg piston if screwed in to far.

If that's a #6 setscrew, you might be able to put a 1/8" diameter roll pin back in there. Either way, you should check the fit so that it fits in the rail without touching the reg piston (grind it or file it), then install it with some red loctite. It shouldn't be a problem after that. The vibration from shooting will make a loose pin or screw move one way or the other.

[sdn137]

Apparently, the zlock pin has been changed to a set screw. If someone drilled it out too far and had to put a screw in there it would be possible to hit the reg piston if screwed in to far. Install the regulator valve pin all the way in. If it sticks out too far the reg seat oring will not seat in the groove. If you can get it down in there and it is loose then change the oring.

So the set screw is not factory? Even on the early models? I'm pretty sure this hasn't been changed, I've owned the gun for over 10 years. Basically though, it is not there to hold the reg piston in place, correct? As in it should not be that tight?


The valve pin sits fine, and the o-ring side of the regulator seat sits fine. It is the other side of the regulator seat that just sits flush with the regulator housing, the black part. It does not sit in a groove at all, really there is no groove there.

Thanks for the reply and the help

[sdn137]

If that's a #6 setscrew, you might be able to put a 1/8" diameter roll pin back in there. Either way, you should check the fit so that it fits in the rail without touching the reg piston (grind it or file it), then install it with some red loctite. It shouldn't be a problem after that. The vibration from shooting will make a loose pin or screw move one way or the other.

Thanks for the reply. Is there any problem leaving it as a set screw? Once I backed it off a little the reg piston fell right out. There should be no leak potential there, right?

[blackdeath1k]

So the set screw is not factory? Even on the early models?

I've had my classic RT since 2000. Bought it used. But mine has a roll pin in it just like my old 95 classic 68automag had.

[Ando]

I know for sure my lvl 5 classic valve as a set screw. As far as a RT's go, I've never seen one in person or on the forums.

Is there any problem leaving it as a set screw? Once I backed it off a little the reg piston fell right out. There should be no leak potential there, right?

none at all

[blackdeath1k]

I know for sure my lvl 5 classic

How old is that one? In 05 it was a roll pin with a hard nose bolt.

[Spider-TW]

How old is that one? In 05 it was a roll pin with a hard nose bolt.

Level 5s were about '90 or '91

[Spider-TW]

Thanks for the reply. Is there any problem leaving it as a set screw? Once I backed it off a little the reg piston fell right out. There should be no leak potential there, right?

Does the reg piston still have an o-ring on it? Usually you have coax them out a little bit.

You might want to post a pic of the reg seat you are describing.

[sdn137]

Does the reg piston still have an o-ring on it? Usually you have coax them out a little bit.

You might want to post a pic of the reg seat you are describing.

Yes, the piston has an o-ring. I used the allen wrench to push it out. It would not budge initially, so I got the idea to loosen the set screw, which worked. When re-assembling, I wasn't sure if I needed to tighten that set screw back down.

The pic in the op is of the o-ring side of the reg seat, and the black housing that it sits on. The video, and others on here, have mentioned that the reg seat should sit down in a recessed area in the housing. Mine has no area like that, the reg valve pin holds the seat in place. Here is another pic of the seat.

Thanks for the help, sorry for the poor descriptions!

[Spider-TW]

Yes, the piston has an o-ring. I used the allen wrench to push it out. It would not budge initially, so I got the idea to loosen the set screw, which worked. When re-assembling, I wasn't sure if I needed to tighten that set screw back down.

The pic in the op is of the o-ring side of the reg seat, and the black housing that it sits on. The video, and others on here, have mentioned that the reg seat should sit down in a recessed area in the housing. Mine has no area like that, the reg valve pin holds the seat in place. Here is another pic of the seat.

Thanks for the help, sorry for the poor descriptions!

You definitely need to loctite that set screw. It would chew on the piston if it turned in.

It's hard to tell from that angle. Look at this animation. The groove is open, but the o-ring sits in there.

http://www.zdspb.com/media/tech/animations/rtemag_6fps.gif

Also check this layout...

http://www.airgundesignsusa.com/downloads/retroexploded1.pdf

Your seat holder looks a little different, but not wrong. There's an o-ring on each side of the holder essentially.

The color of your o-rings looks good.

[sdn137]

Thanks to all for the help. I guess there's only one way to be sure... test it! Hopefully it rips like it used to.

[Tunaman]

The picture you posted is not the reg seat. That is in the other half of the valve.

[sdn137]

The picture you posted is not the reg seat. That is in the other half of the valve.

Sorry, maybe my terminology is wrong. Here is the part I'm talking about from AGD's website, they are calling it a regulator seat holder. That's where I got the name.