Need help with a leaking 1377

[kirby999]

I bought this 1377 used and it worked great for 1 day . It's phase 3 . Now it leaks out the barrel when pumping . If I cock the gun it doesn't leak (now).Although, it did leak when pumping ,even when cocked before I cleaned the valve and everything internally , then removed burrs at the pump end of tube before installing a new #9 o-ring on valve . Lubed everything with Pellgun oil and reassembled . Valve spring is factory . Any clues? I like to leave 3 pumps in my guns but not cocked and can't do this to this one until I get it to seal without cocking. As luck will have it I had just finished setting this one up to shoot this weekend. I'd already made a mildot holdover chart and was it was shooting great . kirby

[kirby999]

I think I've determined it has a weak valve spring . I'm going to use it as is for now, as long as the power stays the same . I'll just cock it before pumping . kirby

[miked6762]

Try cocking only to the first "click"-where the trigger seems to set, then pumping her up. Cock fully after pumping. Be careful pumping when fully cocked-mine can go off unexpectedly like that.

[kirby999]

Thanks for the tip . I never load a pellet in until I'm ready to shoot anyways , So now problem . I shot it today through the chrony and the power is where I would expect it to be and fairly consistent. Within 8-10fps . There's a lot of PCP shooters out there that would love to have that kind of shot consistency . kirby