Pump Cup / Piston Problems in 1377

[Trigg603]

Hey guys, I was pumping my pretty new 1377 today and the pump cup separated from the piston.  When I took it apart it looked like there was just some kind of white glue WAS holding the cup in the piston.  Is this the case?  If so, what do you guys suggest I use to glue it back?  Clearly, the stuff Crosman used wasn't sufficient for the job.

Thanks in advance for any advice, etc.  Have a great evening, gentlemen!

[bigfish123]

I've had this happen on my 1377 also. I took the piston and cup out put the cup back into the piston. Drilled a small hole thru piston and cup and inserted a small pin. This is how the cup was secured on my 2289g.

[Rivers3Plinker]

While you're at it, shim the cup and stuff the piston to gain significant power. There are numerous posts on it here. Seems many get same FPS gain as a flat top piston and valve this way.