Thank you for posting - this is coming at a perfect time for me.So - did I read this correctly?Outer valve ring, inner valve ring PLUS a ring "008" as well inside the valve? Where does this last ring go? I expect to be doing a few of these valves soon.Do you find the new pistons were a good purchase compared to the vintage pistons? If so, sounds like a smart upgrade.cheers
And that’s how it starts! Soon you’ll tackle another. that valve design is similar through many crosman models.I’ve never tried an O-ring in the valve poppet, good to know it worked.
Hey folks,Thought I'd share this here so that others could also learn from my experience. Have two vintage 1377's, probably manufactured around 1990, that were in need of a small overhaul. After spending a fair amount of time on Google and YouTube, I got brave enough to tear one down enough to check out the innards. Here's what I did:Bought Harbor Freight's $8 pack of 300+ o-ringsEnded up having to buy 2 new pistons + piston cups (just went for the standard black factory ones) off of eBayDid a mostly complete teardown of each 1377. Replaced the following o-rings:Outside valve = use o-ring -111 from the pack.Inside valve (the one that separates the 2 halves) = use o-ring -012 from the pack.Then, I dug out the old sealant material in the valve piston, that sealant material seemed waxy and a bit flaky. Threw that away. Replace with o-ring -008 from the pack, it fits right into the old groove area where the old sealant material was. This is the step that I didn't find a whole lot of information on out there on the 'net, seems most folks just buy replacement valve pistons, but I don't think you have to. I have the older brass valve pistons, and after searching and finding nylon / Delrin replacements going for $8 on line, I figured I had to try to salvage the brass ones I've already got. Seems like this approach was the answer.Added a light coat of Crosman Pellgun oil on the new piston cup.Reassembled.Test dry fired. Both would now hold compression and discharge normally.I'll be testing over the next few days but it seems I've been successfully able to revive these two 1377's so far.Turby
The first 3-4 digits in the serial number will be a date code, in case you want to know when they were actually made instead of when they were " probably " made.
Those HF O-rings are not really high quality, but I do use them for other purposes and for size reference.
If trigger frame screw causes failure … I’d look at the outside valve O-ring. As the screw tightens it pulls the valve to 1 side of the compression tube. Maybe try the next size up HF O-ring since they are a softer material than OEM.
I just rebuilt an old 1377 today that has no serial number. It is an old one that has the pull-to-cock mechanism and sliding breech cover. I guess its what they call Phase two, but should it not also have a serial number?