GTA
All Springer/NP/PCP Air Gun Discussion General => Vintage Air Gun Gate => Topic started by: mastee on January 11, 2019, 05:16:35 PM
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Hello From Washington,
Pickedup a Remington am77 and an old daisy 880 last week.
The daisy is not holding pressure, I am starting to take it apart, cleaning the gunk, just ordered the reseal kit for o-rings and felt washer, a 901 mid barbell spacer (12 138390-000 MID BARREL SUPPORT $ 1.00), the bumper has deteriorated and is old style so I think will need to replace it with some washers per the thread below:
https://www.gatewaytoairguns.org/GTA/index.php?topic=99840.260 (https://www.gatewaytoairguns.org/GTA/index.php?topic=99840.260)
The removal of the trigger spring will be done as recommended
Do I need to do anything to the piston, it is flat faced but does the raised part need to be grinded and sanded?
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Did you order the vintage reseal kit for it? That is an 880 from the 70's by the look of the pump arm. The check valve rubber will be different than the later model 880's. You may even have that weird spring loaded check rubber. First pick is of the typical early 880 check rubber cup from the 80's-90's. Second pick is of the weird very early spring loaded check rubber circa early to mid 70's. Third pic is of the two assemblies side by side.
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Just realized I should send you a pic of the modern 880 check rubber......Daisy went through 3 incarnations. The right hand check rubber is the typical one for most 880's made from the late 70's through the 80's and into the 90's......I think. The one on the right is the modern check rubber. You definitely do not have the modern one in your rifle. Hope this helps. Good luck in your reseal. It is not very hard so long as you have the right reseal kit. :D
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Whoooooops here are the pics. Senior moment.
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Just finished complete tear down, it is the one in the 2nd pic with the spring and a brass tube. All parts are in good condition except the felt viper and the rubber bumper on the piston, the kits at Daisy were $1 and so was the spacer, I should be able to use the O rings and the felt viper, correct?
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Everything in the modern kit will work fine except for the check rubber. In the modern kit it's a rubber donut. In the older guns it's more like a cup with a flange on it. See pics. You may get lucky and the check rubber works fine. I would doubt it. If it works fine great! If it doesn't you will get it back together and it will only hold one pump. All successive pumps will push back against the piston/pump arm.
Good luck. Them older 880's are nice hefty guns.
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Posted this on another 880 topic. It's a check cup fix for older 880's. Uses an o-ring inside the check check cup. Worked on my 880.
https://www.youtube.com/watch?v=hftQpPMzGd4 (https://www.youtube.com/watch?v=hftQpPMzGd4)
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Perfect Video, thanks
The seal kits should be here this week. I got impatient, cleaned it up and put it back together with some metal washers and a felt dremel washer (which I over butchered) on the piston but no luck, the insides were surprisingly clean though (thin golden oil every where), the check valve with the spring has a Oring behind it, its like sandwiched between the valve body and check valve and is thicker than my 1322s piston and valve O rings.
I will take pics on the next disassembly, if it holds pressure the trigger and sear could be a good candidate for opposing magnet mod as well, I love it on my 1322
Will post an update soon
btw also pickedup a model 2001, 35 shot repeater, the mag is a bit of work but in the 60ish F morning temp, I got 35ish shots starting at 575 fps, Daisy wadcutters, I have a F1 chrony, quiet a bit of fun actually, my first couple of Daisys
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opposing magnet mod as well, I love it on my 1322
I'm curious about this mod. I have not heard of it before now. Do you have a link or can you describe it in more detail?
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22lr shell jb welded to the frame and magnet jb welded on top, another magnet with the opposing pole jb welded to the sear bottom, so that sear repels away. Install sear after they have cured or they will shift, also watch for magnet clearance on the internal sides of grip frame.
Once cured you can stack additional magnets to change the trigger weight, much much smoother than before
listed in this thread as well
https://www.gatewaytoairguns.org/GTA/index.php?topic=92727.0 (https://www.gatewaytoairguns.org/GTA/index.php?topic=92727.0)
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That's an interesting concept there. I can see how that would work for the Crosman 13xx's as all that spring does is seat the sear upon cocking. On the 880 however, the spring between the trigger and sear applies the pressure required to open the valve after the trigger releases the sear. I can't see how a magnet could come into play.
I'm interested to see how this works out for you.
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That oring trick inside the check valve is something that I tried myself a few years back. I could not get it to work on my older 880's. Nothing would pump through it with the oring I thought was a good fit. I'll try it again with a slightly smaller oring. That would be a real simple DIY to bring back an older failed check valve. I've even tried forcing in a big oring to really flare out the cup and then leave it to soak in HOT ATF. I soaked it for 6-8 hours on my electric baseboard, in a glass bowl. The oil had to be near 200 F. Didn't change it's shape at all.
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I took it apart again, so I see the point about the magnets, i stand corrected.
Also I still haven't received my seal kits from Daisy been over a week, so tried 113 from my O-ring kit per the video above, it still leaks but I think from somewhere else now
Edit Jan 20th:
Bought the danco kit form the video above, but no luck:(. The piston has good compression as it sucked out the brass tube to front and I can also feel the suction when installing the piston as well.
Changed the Valve O ring with a #7, installed with 2 threads worth of yellow Teflon tape.
I installed the valve body and only the piston with pump arm, closed the poppet, I should be able to pump air into the valve correct? I feel like the air leaks out before or around the valve (also tried 1 and then two #10 O rings stacked, per the video), the air is not being pumped into the valve