I have an old Ted Williams 880 799.19720. Needs reseal. Can I just replace the guts will those from new 880 or do I need the older seal kit kit?Kit from JD airguns is $33.60 New 880 at Walmart is $38.
Some guys get good results with an alcohol flush and relube. Who knows, you might get lucky, and the cost is nil. AT stop leak has been used successfully to give some life to old abutment seals. I've not tried it yet but I do have a bottle of stop leak if the need arises.If it was me I'd take it down and thoroughly clean it, replace the piston O-ring, relube it and see what I had then. The exhaust valve can be checked for leakage once the compression tube and abutment seal assembly is removed from the valve body by pulling a suction through the valve body with the valve closed. If there's leakage there it may be between the seat in the valve body and plastic valve seal. Or it could be the O-ring on the stem or outer O-ring. Outer O-ring is easy to replace, stem O-ring is not easy. Replacement screw-in valve are also available. I have heard (but have not tried it) that the new exhaust valve stem and stem O-ring can be used in an old valve. New exh. valves are available from Daisy for $3.Good luck, whatever you do.
Just tried the 0-ring shim on the check valve. Seems to have worked. While probably not up to spec (no crony test) it is shooting much harder. Good enough to hit spinners at 10yds. And at least it shows that the check valve was the issue. It's the first time I've worked on an 880. After taking it apart a few times the design seems simple.