Hoping for some help got a Crosman 760 1st Variant and when It pumps up it loses air but nothing happens when pulling the trigger not even a click or pop. I checked the barrel and nothing jammed and pump forearm is not loose. Most likely needs new seals but still thought it would click or pop when pulling the trigger. Any ideas would be appreciated.
Crosman 760 1st Variant Do I need new seals
- Thread starter ETA
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Wow! That's as fine an example of that model as I've ever seen. Does it have the square stock tang?
If it isn't holding any air at all, it's probably either the pump-cup not putting any in, or the quad-seal failing to hold what air is getting in.
I'd try an alcohol flush first, then follow it up with some motorcycle fork oil, Alphabet org (Auto Trans Fluid), or 30-weight non-detergent motor oil to see if it seals back up. To flush it, just spoon a couple of tablespoons of rubbing alcohol into the pump and pump it through. That will flush any garbage through the system and hopefully let the seals (once oiled) return to working order. If the pump-cup isn't sealing, oil will help that too. Parts are still available, so you're not out of luck.
If it's the quad-seal, you can replace it with an o-ring like the one in the photo. You'll find the manual and exploded parts-sheet on the Crosman website. Those are pretty easy to work on and a lot of fun to shoot.
Good luck,
J~
If it isn't holding any air at all, it's probably either the pump-cup not putting any in, or the quad-seal failing to hold what air is getting in.
I'd try an alcohol flush first, then follow it up with some motorcycle fork oil, Alphabet org (Auto Trans Fluid), or 30-weight non-detergent motor oil to see if it seals back up. To flush it, just spoon a couple of tablespoons of rubbing alcohol into the pump and pump it through. That will flush any garbage through the system and hopefully let the seals (once oiled) return to working order. If the pump-cup isn't sealing, oil will help that too. Parts are still available, so you're not out of luck.
If it's the quad-seal, you can replace it with an o-ring like the one in the photo. You'll find the manual and exploded parts-sheet on the Crosman website. Those are pretty easy to work on and a lot of fun to shoot.
Good luck,
J~
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Appreciate the help not sure about the stock tang but here’s a photo of the other side. I saw the alcohol flush on YouTube and definitely worth a try. This has a bit of surface rust but only on the barrel and with a little oil would not be very noticeable. Been really enjoying the older airguns they feel so nice in hand with less plastic. Got this on the auction site for 125 seller said it was recently resealed and a great shooter so I’m still deciding to return it or take a small refund. Have a Daisy 814 and 880 both need seals but still hear the action click when the trigger is pulled and wondering if anyone has experienced a similar dead response like this one
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Your rifle uses a blow off valve type of system. There is a valve cap that sits over a small nipple on the rear end of the valve. When the inner seal fails, the air will leak out of the rifle almost as fast as you can pump it up. This often sounds like a fart for lack of a better description. In all likelyhood the cap seal is shot. Sometimes the o-ring that seals the valve within the tube will let go. This will result in no air being fed into the valve as it passes by the valve instead when you're pumping it up.
Lastly, the trigger is what keeps the valve cap in place until it's pulled. If the trigger is not engaging with the valve cap, the gun will not pump up as the cap will simply blow out of the way thus leaving the valve empty. A rebuild kit should be easily found on Ebay or by any authorized Crosman repair facility.
Lastly, the trigger is what keeps the valve cap in place until it's pulled. If the trigger is not engaging with the valve cap, the gun will not pump up as the cap will simply blow out of the way thus leaving the valve empty. A rebuild kit should be easily found on Ebay or by any authorized Crosman repair facility.
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What Razor62 said.
And...
Here's a view of the valve system disassembled. And another pic of the quad-seal inside the nipple that goes on the valve. That's where the o-ring I posted about goes.
And a pic of the tang on my tootsie-roll model. You can see that it's rounded where it attaches to the receiver. If it's square on yours, then it's a first production model. They changed it the next year, (I think).
And another pic of the front of the pump-pivot beneath the barrel. If you find numbers there, it will be the month and year of production. This one is April of '72.
You should be able to source all of the o-rings at any good hardware store once you know the sizes. Standard rubber o-rings will work just fine.
These guns are sorta special to me, as my late brother had one that he shared with me on occasion.
Good luck,
J~
And...
Here's a view of the valve system disassembled. And another pic of the quad-seal inside the nipple that goes on the valve. That's where the o-ring I posted about goes.
And a pic of the tang on my tootsie-roll model. You can see that it's rounded where it attaches to the receiver. If it's square on yours, then it's a first production model. They changed it the next year, (I think).
And another pic of the front of the pump-pivot beneath the barrel. If you find numbers there, it will be the month and year of production. This one is April of '72.
You should be able to source all of the o-rings at any good hardware store once you know the sizes. Standard rubber o-rings will work just fine.
These guns are sorta special to me, as my late brother had one that he shared with me on occasion.
Good luck,
J~
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Thanks for the info and helpful photos the tang on my 760 is round so unfortunately not first production it was made in April 1970.
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