Thursday, February 4, 2010

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.


Andrew said...

Superb detailed record of your work - thank you very much for sharing your experience, I've recently acquired a 147 and going through the process of restoration and resealing has been made much simpler thanks to your help! Thanks again

Wellington, New Zealand.

andrew said...

I know this is an older post, but in case you're still around:
What does the number "114" mean on that end breach plug? I have a 140 and it says "63", and I'm curious what it means.

Felice Luftschein said...

I always assumed (in other words I never checked) it was the same part used on a Crosman model 114, but if yours says 63, now I'm not so sure...

Ted Koski said...

I have the 140. I bought the complete replace kit including the plastic piston plunger cap. I replaced all of the seals, reassembled the gun and still it wont hold air. It held air one time on the first try and thereafter nothing. I have taken it apart 6 times and find nothing wrong with the new seals.

Nick Carter said...

Check for burrs on the pop off valve and inlet valve face, check for dirt, etc. It's possible the hammer isn't holding the pop off valve closed as well - may be binding or the sear may be malfunctioning. Other than that I'm not sure, try asking on the Crosman forum perhaps.

Shadowfax said...

I recovered my 140 I got in 1966 or so from my parents house where it had sat in the basement all these years.
Hadn't been shot in say 45 years.
It seems to work perfectly!I hav'nt left it pumped up yet but I don't hear any air escaping.
Should I leave well enough along or refurbish it?
I'm quite impressed it still works after all these years.

Nick Carter said...

If it works, it works, I'd leave it alone besides a light oiling and dusting.

Alan Williams said...

How do you remove and reinstall the Quattro ring without removing the pressed on retainer ring? Where can a person get a Quattro ring without having to buy the entire o-ring set?

Alan Williams said...
This comment has been removed by the author.
Nick Carter said...

You remove it with a dental pick, and you can sort of massage it into place with a small dowel/toothpick, etc. There is no need to disassemble the cap at all.

rocky said...

I'm trying to restore a 140 for a friend and having hard time finding pump felt. I also need to find out how to install it.

Anonymous said...

In about 1960, I got a Crosman 140, sold by Sears under the number 126.19300, and within a few years, had to replace the entire valve as its internal parts seemed unavailable to me. Long after that but still long ago, I found the 5/16" OD, 3/16" ID quad ring was available through seal and bearing dealers; its industry number is AS568A-008, and it's sold in packages of 100 for ten or fifteen dollars from places like MSC Industrial Supply.
BTW, I believe the stamped number on the breech plug corresponded to the part number on Crosman's schematic.

Anonymous said...

I just did a bit more looking and find that McMaster-Carr has an even lower price, about $8 per hundred for Buna-N AS568A-08 quad rings:

(I don't know if that link will be posted; if not, use their part number 90025K127 in a search)