Monday, October 20, 2008

Getting a Crosman 140 Working, Part 1

Well, I bought another "pile-o-parts" airgun, a Crosman 140. It was mostly in pieces so I took everything else apart and cleaned the gunk off.

The main parts. Not shown are the pump components, stock, tube and the barrel

The valve. It's a pop-off valve, held under pressure by the sear. When the trigger is released the cap at the right pops off and releases the air.

The piston rod that came with the rifle is at the bottom. Someone tried unsuccessfully to remove the old seal, and did what looks like a bunch of grinding on it. The top rod assembly came as a spare with the Crosman 101 pile-o-parts I bought a while back. So I figured that I'd use it instead.

The 101 piston parts, and a new seal that also came with the 101. Since I'm nowhere near close to working on the 101 I figured I'd use it here.

The new piston head.

The valve o-rings were removed and replaced with new ones. The pop off valve has an internal quad seal. Later on in the process I ended up replacing it with an o-ring which will probably not last. I'll be ordering in the proper seal soon.

The assembled valve. Those marks were made by the previous owner. Really...

The valve is held in by the stock screw. I wish it had flats on it for a wrench.

The pivot pin is a spring pin. How I hate pushing it in and out when setting the optimum piston rod distance, as well as getting the valve assembled correctly.

The trigger group looks a lot like the 160 trigger, but is simpler as it only retains the "hammer" against the valve pressure. The front screw holding it to the tube is temporary. I didn't bother putting the barrel on yet.


Anonymous said...

I have a crosman 140, I am looking for parts to get it working again, need the seal and the brass insert on the end of the piston rod.

Richard Tucker, PMP said... can assist you with parts and reasonable service.

I own a Crosman 140.

Richard - in Virginia

Anonymous said...

I also have a Crossman 140 and i need the seal.

Nick Carter said...

For parts and service you can try Bryan and Associates, Mac1, Precision Pellet or JG airguns.

Tell them the blog sent you.

John said...

The piston rod that came with the 140 rifle is just like the one you have in the pic at the bottom (in the comparative snap of the 2 pistons). It has a press fit lock to hold the washer in place, this lock and washer come off when i pump and i am not able to make them stay in place - any ideas on what i can do- should i have the piston end threaded and then put in a nut or try some super glue to hold the press fit in place. Would appreciate a reply.
Thank you.

Nick Carter said...

You could try one of the loctite bearing retaining compounds - it's pretty strong and will fill a large gap.

John said...

Thanks Nick, i will try Araldite and see how it goes.

John said...

Hi Nick,
Ive used Araldite after degreasing - works fine and i hope will continue to do so.
Thank you for your help.

Unknown said...

hey, i have a Crosman model 102 and it wont pump up. it wont hold air at all.
i was woundering if you might know what is wrong and how to fix it?


email me at

Felice Luftschein said...

You need new seals and pump cup.
For reseal kits, parts and service you can try Bryan and Associates, Mac1, Precision Pellet or JG airguns.

keith said...

i owned a 140/it would take as much air as you could pump

Unknown said...

I have a crosman 140 that I rebuilt. when I put it all together and gave it 3 pumps pulled the trigger it did not fire.though it held no air, when I took it apart again as I unscrew
it from the brass valve then the air came out so I know it's holding air,some how the trigger
is not doing it's job. checked everything all looks good did this 3 times with same results.what am I doing wrong?
I have the simple type trigger.

David said...

Any hot tips on removing the quad seal from the pop off valve? It is not coming out and Um not looking forward to putting the new one in.
Thanks, David

Nick Carter said...

It's probably hardened as they do with age so you'll need to dig it out with sharp picks.