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Old 07-27-2008, 07:55 PM   #1 (permalink)
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AGD Flatline Rebuild Guide (56k beware)


Ok, folks, if you are like me and enjoy running regs that have a ridiculously high out put range AND a fast recharge rate, you are in luck. Here is a disassembly and reassembly guide that is right up your alley!

The Flatline regulator is a classic reg from Airgun Designs that could make any modern regulator blush... Basically, it combines a stratospherically high out-put with a disgustingly fast recharge rate. And the best part is, they are very cheap and easy to find these days! So, for about 7 bucks in o-rings and about an hour of your time, you can have yourself a really nice adjustable reg.

One side note: This guide is for a 3000 psi Flatline. There are 4500 psi Flatlines are out there, but sadly they not as good (as the 3000 psi version) in my humble opinion. The 4500 psi Flatlines need to be rebuilt quite often and suffer from some odd problems.

Oh, and just for clarification, this reg was sitting in some basement for a decade, this is essentially documenting my rescue effort. But... Onto the guide:

1) Clear a space. Do yourself a favor, clear a large space on a flat table. Vacuum the floor, and made sure it is clean. This makes finding a lost part very easy later.

2) Assemble your tools + parts: You WILL need the following tools...

* 7/32 Allen wrench
* 1/8 Allen wrench
* .050 Allen wrench (the tiny one)
* 7/16 wrench
* Dental pick or probe
* Teflon tape or Loctite thread locker
* AGD Flatline rebuild kit
* Q - Tips
* Paper towels
* Bin for parts
* Gold Cup (BE VERY CAREFUL USING THIS, I will explain later)


Item(s) that would be handy to have...

* C-clip ring tool
* Razor knife
* Tom Kaye


3) Let's Begin: OK, now that you have all of your tools and a clean space to work, let us begin the disassembly. Take your tank + reg and separate them. PLEASE ENSURE THAT THE TANK IS EMPTY!


IMG_0637.JPG (See how the tank is empty :-p)


Now, separate the front pressure regulator. It should just come off with a twist.


Take the pressure regulator and set it aside in your bin for now. Now, see that is not such a bad start!

4) Disassembling the On/Off: Grab your .050 Allen wrench and remove the On/Off knob screw.


Pop the On/Off... off (haha)


Examine what you have so far...


Now, with your finger and with a tool, push down on the On/Off until it comes out the other side.



Keep Pushing until you can remove it with your fingers.


And put it into your parts bin...


Now, with your pick, remove the On/Off spacer.



You may or may not be able to see it inside of the On/Off port. If you can't... Give the reg a love tap on your hand (A La, bang in on your palm). It should work it self out. But, if you still cannot get it out... Do not be worried. It will come out at some point further along in the disassembly, just be ready if it falls out and rolls away.

5) Disassembling the tank portion: Turn the reg over and examine the portion that screws into the tank:


Remove the C-clip by using a C-clip tool or being VERY carful and using for dental tools...


Once the c-clip is loose, remove it.


Pull out the spacer and reg spring:


And inspect what you have pulled out for that area thus far...

Next take a look down the reg and look for the on/ off valve.

IMG_0665.JPG (sorry bad pic)

Using your dental tool again, push down on that valve and give the reg a few whacks against your palm to remove the it.




Sweet! We are now cooking with gas! Take one last look down the reg, if you see the ball bearing, you are in good shape!


6) The pressure regulator: Set all of those parts you were just working with aside and grab the pressure regulator from earlier. And pop that tiny o ring on the top off.


Next back out the pressure adjustment all the way (just like on a mag).


Haha, if you have been through a mag before, this should look familiar. Note: Be careful with the spring pack in there. It is packed with grease that NEEDS to stay on there!


Now look down the pressure regulator and using your 7/32 allen, back the piston out of there.



And, now you have a disassembled reg!


7) Re o-ringing the Pressure Regulator: Get that main o ring off of the body and slap the new one on...


Redo the o ring on the piston.


Push the piton back into place using your dental tool or your wrench.

Pop the new tiny o ring onto the top. Should be the second smallest o ring in the pack.


Put the adjustment and spring pack back in...

And look, we are nearly there!


8) Redoing the back portion: Slap a new o ring onto the on/off valve.


Reassemble the rear tank portion.


SIDE NOTE: For some reason, the c-clip in my kit DOES NOT FIT!!!! BE WARNED. The clip that came out of my reg is on the left, the one from the kit is on the right. I a going to call AGD about this tomorrow morning!


Push it all back in EXEPCT the spacer and c-clip. Put the valve, spring, and spacer in, in that order. Then seat the whole thing with your wrench.


Next push in the c-clip and seat it with your c-clip tool or a dental tool


Next, inspect the on/off tube, do you see the top of the valve?

Next, using your dental tool, add back the spacer. MAKE SURE THE CONCAVITY OF THE SPACER MATCHES THE CONCAVITY OF THE ON/OFF WALL!



Then, using your dental tool, push it down so that the spacer is flush with the rest of the surface. If it does not go in flush, reassemble the on-off switch FIRST.

Next, get those old o rings off of the On/Off, and put the new ones on...




Then push the on/off back into the reg, ENSURING that the cam in the center of the on/off in vertical, or in the 'up and down' position!



Next, put the on/off knob back on top and screw in the on/off retaining screw.

Lastly,put a new tank o ring on. (Sorry I do not have a picture for this on). But, it should be very easy. Basically, it is only o ring in the previous picture (Bottom left hand corner)

Now, Screw the Pressure Regulator back into the Rear assembly. Make sure to torque down to at lease 25 pounds...


9) Fill Nipple and Check Valve... Using your 7/16 wrench, Take the fill nipple off.


Take out the check valve.


By any means necessary (knife in my case), remove the old o ring. Then slap the new one in. It should be the smallest o ring in the pack.


Then, use some thread locker or teflon tape and screw the fill nipple and valve back in...

And one last picture of all the tools I used...


IMPORTANT NOTE: I used a small amount of of gold cup to clean crap out of my reg while I was disassembling it. I would ADVISE AGAINST using it unless you know what you are doing!!!!!!

For instance, if you accidentally used gold cup oil ANYWHERE near your fill nipple, you run the risk of turning your reg and bottle into a diesel engine....

Think of it this way... OIL + HEAT + COMPRESSION + 0^2 = MASSIVE BOOM!

And no... the danger in not just localized to your fill nipple... if you don't know where it is safe to use. DO NOT USE IT! Basically is you are forced to use it, only use it FORWARD of the on/off, and make sure to wipe up ANY excess...

And you have a new reg! Hope you guys enjoyed the read!


Last edited by Captainneeda; 02-01-2018 at 09:49 PM. Reason: Cleaned up the photos
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