Crosman 130

[Bam86]

Hi All,

Not sure if this goes here as Vintage, or Air Pistols.

Working on rebuilding an old Crosman 130 air pistol. I had it working for a while, but after setting way too long, it won't pump up. With each pump, I hear air escaping out the barrel. So my guess is new o-rings. Got it apart and looking at the o-rings, all appear to be good, but going to replace them anyway. The last time I rebuilt it, I couldn't find any good listing of the proper o-rings, and just guessed. I see you can buy a pre-packaged kit of o-rings on line, but Gee spending $8. or more just for some o-rings seems outrageous. I have an industrial supplier locally, and the parts counter guy also likes to shoot airguns, so usually I can get them for free.

Does anyone know the proper o-ring sizes?

I have come up with #008, #011, #111 for the ones in the valve assembly, but just not positive. They seemed to work the last time, but obviously not long enough.

Any assistance would be helpful. Also, does anyone have a parts diagram? The only ones that I can find on-line don't seem to match my gun. They are for the 1953-1954 version that was changed. Mine is obviously a later manufacture.

Enjoy and Good shooting.

 

[nervoustrig]

What material and durometer were the short-lived ones? Buna-N in 70 durometer should work well everywhere on a pumper. Perhaps polyurethane on the pump head for its superior abrasion resistance (if it uses an O-ring...a cup has been the common thing for many years).

 

[Bam86]

Not sure of the durometer, but I believe they were all Buna-N last time. Yes, the pump head on mine is the cup. I think it is fine since I hear air moving out the barrel when I try to pump it.

Just want to verify the correct size. I think I have it right, but would love to have confirmation.

Enjoy.

 

[MScottLeeman]

McMaster Carr is a great place to look as is The O'ring Store. For just a couple dollars you can get Hundreds of o'rings. No need to get robbed for just a couple. McMasters has nearly Anything you could as for!

Mike

 

[Bam86]

Also, does anyone know the size of the screw that holds the rear sight onto this pistol?

I made a new rear sight, but can't quite figure out what size screw it is that holds the sight on.

On another note, got the o-rings this morning, and it seals up really well. So those are apparently the right sizes. Hopefully they will last a while again. If not, I got extras now.

Thanks,

BAM86

 

[marflow]

it could have been the hammer sitting on the valve stem and over time pushed it in a very little

did you lube it up at all as you were have the sealing problem, sometimes if you can ahead of the leak you can get it seal but then again it takes the small amount of crud on the valve to cause the leak, you will never see it and always wonder what it was

my view is lube first and tear down next

 

[AirNGasman]

Sounds to me like it might not be an o-ring problem at all; rather, an exhaust valve not sealing.

 

[Bob-in-WV]

I think it would be the exhaust valve too, if it is leaking through the barrel. Some of the old Crosman pumpers have a quad o-ring inside of the exhaust valve. It is a pain to get the old one out and the new one in, but it can be done. Just be careful and don't scratch the brass.

Bob in WV

 

[Jonah]

Not sure, but think the rear sight screw is an 8 x 32 tpi.

 

[Bam86]

Thanks all,

Changed all three o-rings. Used a little diver silicone grease, carefully wiped off valve and brass seating surface. Reassembled, and no leaks.

Still trying to figure out the little screw that holds the rear sight on. Much smaller than an 8x32.

Enjoy.

 

[Jonah]

Bam86;

You must be asking about the elevation slide screw. If so, it is a very small wood like screw. You probably won't find one, but go to a hardware store and select the smallest wood screw that will fit thru the slot and screw it into the plastic sight. OR, go to Crosman and pay a lot for the screw and shipping. A lot of electronic devises also use small screws into plastic. Might find one that will work.

 

[Bam86]

Got the rear sight bolt size figured out. In case anyone is ever looking, it is a 4-40. I had a tap that size and carefully used it to clean the dirt out of the threads, didn't remove any metal. Then got a little socket head cap screw in size 4 - 40 tpi, and it worked perfectly.

Sight is mounted.

Tried it out and pretty much dead on at 30 feet with 5 pumps.

Back in business. Enjoy all.