Tuesday, November 8, 2011

Healthways Plainsman BB Pistol Disassembly, Part 3

Almost done…

11041141 
The barrel end of the feed mechanism.

11041142
The BB hopper side of the feed mechanism.

11041143
The valve assembly is just pushed into the CO2 tube.
The cartridge is pierced and fills this chamber with gas. The o-ring was hard, it’s amazing that it was holding gas at all.

11041144
A snap ring holds the exhaust valve in the body.

11041145
Ok, a snap ring and a spring star washer holds the exhaust valve in the body.

11041146
I had to gently lever out the spring washer. The disk with the 4 holes allows the gas to flow.

11041147
Valve assembly.

11041148
For some reason the stem has a ground bevel on the end. Since there’s nothing to hold it in a particular orientation (unless it’s carefully aligned at the factory and then stays put?) I don’t see why.
I’m assuming that the rim of the seal holds the valve seal in?

11041149
I can’t tell if the stem is soldered, screwed or pressed in. No hint from the spring end. This is odd as the rest of the pistol is so repairable. But making a new valve stem would be easy I suppose. The pin diameter is the same as the Crosman guns from the era, but the seal is more like a Benjamin or Sheridan. I'll reuse it and if it leaks then I'll worry about making a replacement.
   
11041150
A standard sealing lip inside.

11041151
The cutouts in the valve body allow gas to flow around the end of the CO2 cartridge and into the valve.

11041152
The piercing assembly. Clip was levered out with a stout dental pick.

11041153
The piercing pin was pushed out from the other side (I opened the lever and wedged the pick up and into the hole.

11041154
An o-ring seals the pin.

11041155
It fits in this cup that looks to be staked in place. Yes, I put those two scratches at 12:00 on it. Oh well. It doesn’t matter.

11041156
I decided not to punch the lever pin out. those three notches means that it’s a press fit and has cut into the hole material. Better to leave it and not risk loosening the pin. The o-ring around the body (on the left) was hard as a rock.

11041157
A setscrew underneath the muzzle end of the frame.

11041158
Removed and a bushing for the barrel slips out.
So overall this was a unique design. I love design from this die cast era. Compared to the Roger or other die cast pistols, this has superior quality.

I’ll need to get some more 8 gram cartridges (I used up all I had with the Benjamin 30/30 debacle) to test after I get it back together.

2 comments:

kathy antrim said...

11041143
The valve assembly is just pushed into the CO2 tube.
The cartridge is pierced and fills this chamber with gas. The o-ring was hard, it’s amazing that it was holding gas at all.


How did you pull out the valve assembly from the tube?
I tried pulling it out by hand and it won't twist out either.
I didn't want to damage the valve assembly.

Felice Luftschein said...

I think I just used a wood dowel or brass rod. Likely it's stuck with dried up oil & grease and decomposed o-ring. Try spraying some WD-40 or other light lube and see if that helps. Although it could be different, not sure if there are variations on the design over the years.
Nick