Some More Notes on Reassembling a Crosman 140

Just a couple of pictures of what I did to get it working...

I chucked up the breech cap in the Taig lathe.

Filed and sanded smooth. Notice the number 114 on the end...

The two o rings in the valve cap were dry and split when I removed them.

I replaced the square ring with a 008 o-ring.

And the other with a 011

Likewise the valve body got a 012.

And a 111.

Pushing that knurled pin back in with an aluminum c-clamp.

I decided to chuck the transfer port seal in favor of a piece of 1/4" nylon tubing.

I hit the breech cover and breech with some Oxpho blue.

I should have done that cap in the main tube too. Oh well.

The 008 o-ring leaked, so I tried a 4mm x 2mm inside the valve cap. Worked better. It leaks down if left pumped for 48 hours, but not 24. Go figure. I know the last time I used an o-ring I said I'd order in some square seals (Quattro rings) but I never did. Maybe I will now. Anyway it pumps up and shoots. Too rainy to Chrony it but it feels good.
[Update] Ran some shots over the chronograph, got an average of 614 fps with 10 pumps, 14.3 gr. Crosman Premiers.

Crosman Model 140 Disassembly, Part 2

On I go...

With the bolt removed I was able to remove the other breech screw.

And the barrel and breech came off. Unlike the previous 140 the barrel was solidly joined to the breech.

The transfer port seal was really messed up.

Note the stamping "M140" HAWTHORNE", etc...

There's a pressed in threaded bushing that I had to remove. I punched it out. Later I would realize that my roll pin pusher works really well for this.

It's straight knurled.

Probably the biggest pain in disassembling the gun.

The tube cap (Sear Block Stop) comes out under a small amount of spring force.

Nothing fancy.

The hammer, "small tube plug" and "valve pin" drop out.

You can see where a guy with pliers attacked the stock screw.

My gentler alternative, a spare 1/2" jacobs chuck used as a wrench.

The transfer port seal. Note the metal part of the "Breech Gasket Assembly" or transfer port seal.

I used a dowel to push the valve out the front of the tube.

The valve and cap.

Unscrewing the cap reveals the white plastic (teflon?) check valve and spring.

Now the trigger.

Opens up with two screws. Unlike the better 160 trigger there aren't any adjustments.

Huge trigger & sear unit...

Nothing to it. That's everything except the pump cup/plunger stripped.

Crosman Model 140 Disassembly, Part 1

I picked up a Mongomery Wards branded Crosman 140 in December, pretty cheap. It wouldn't pump up but I figured I had already done a strip of the 140 for the blog, until I checked and realized that while I had rebuilt a horrible 140 in parts and Derrick refinished a 147 stock, we hadn't actually disassembled one for the blog. So here I go.

Dark brown stained stock, plain jane 140.

A nice touch on this 140 was the plastic ramp attached to the utilitarian front sight. I'm not sure if all 140s had this or only the MW ones?

The cap on the breech was chewed up, which is a clue that someone has tried to fix it in the past.

To get the stock off I had to remove the safety and unscrew the lock nut.

I put the safety in the neutral poistion and pushed it out. You can see the plunger tip.

I used my roll pin pusher to remove the pivot pin.

The front sight assembly.

The pump arm and piston slid out. The pump plunger pulled vaccuum on the way out which means that it's ok (borne out by later use) so I won't be removing it. Which is a pity as it requires making a tool to remove the pressed on retainer.

Small dowel pin removed.

Now the breech cover.

Screw removed and cover slid off rearwards.

Rear breech screw.

I used an offset screwdriver to remove the trigger assembly.

Put aside for later.

There's a nylon bushing in the hole that had to be pried out.

You can see that someone tried to pry the cap off the breech but didn't realize the nylon bushing had locked it in.

Using the screw as a lever worked fine.

The cap is really chewed up.

Then the bolt comes out. It looks fine, or at least better than the last one.