GTA

Airguns by Make and Model => Benjamin Airguns => Topic started by: sweatyk on May 17, 2025, 12:34:15 PM

Title: 392PA rebuild
Post by: sweatyk on May 17, 2025, 12:34:15 PM
Now that I finished my blue streak, a buddy asked me to bring his 392PA back to life. I'll have to admit this is addictive. Being this is only the 2nd one that I'm doing I still have some questions. I pulled the pump cup assembly first. Noticed that the edges of the rubber cup are chewed up. I took a pic of the mating surface inside and it looks really rough. Almost like it's diamond crusted....lol. How do these get like this? Is this the norm or will I need to smooth this out somehow? I want to resolve this before I move to the rear of the rifle.
Title: Re: 392PA rebuild
Post by: sweatyk on May 17, 2025, 02:30:31 PM
After a closer look it appears the edges of the cup was oily gunk. One little blemish on the cup. Pulled out the valve chamber......very icky  :o

Most of the internal parts look ok but a reseal kit will be installed. It just looks like someone got carried away with oiling it.
Title: Re: 392PA rebuild
Post by: sweatyk on May 17, 2025, 03:02:12 PM
OK now I feel like an idiot. I thought there was a partition in the body between the pump area and the valve area............just looked through one end after removing everything......DUH! I'm such a noob. Anyways I'm going to start cleaning everything while I wait on parts..... :P
Title: Re: 392PA rebuild
Post by: Back_Roads on May 18, 2025, 08:36:28 AM
 Not as bad as you first though good thing :) I do see orings that are at end of life, and pump cup is worn, it will be noticable when side by side with a new one.
Title: Re: 392PA rebuild
Post by: sweatyk on May 18, 2025, 09:22:38 AM
I've really enjoyed doing this. Too bad there's not a big need for this service down here.
Title: Re: 392PA rebuild
Post by: Back_Roads on May 18, 2025, 09:58:16 AM
 You never know, I found a local niche in my part of wisconsin. I started with a Face Book page, I am steering away from and have a paid web site for now, as things are taking off after many years, and I hate FB LOL
Title: Re: 392PA rebuild
Post by: sweatyk on May 21, 2025, 06:03:51 PM
Today I received the seal kit. I have a question about the tiny o-ring in the kit. What does it go to? Next to the smallest was for the bolt but this one I have no idea. Am I missing something? The kit came with 5 o-rings and a new exhaust valve.
Title: Re: 392PA rebuild
Post by: sweatyk on May 21, 2025, 08:12:43 PM
My best guess is that one fits the 392 and the other is for the bolt on the 397? So the kit comes with both.....
Title: Re: 392PA rebuild
Post by: sweatyk on May 21, 2025, 08:57:53 PM
Everything installed and she works perfectly  ;D
Title: Re: 392PA rebuild
Post by: Back_Roads on May 21, 2025, 09:30:41 PM
 You nailed it, and yes the tiny one is for the .177 probe.
Title: Re: 392PA rebuild
Post by: sweatyk on May 22, 2025, 09:13:15 AM
Now that it's done I feel empty. Of course I'm glad it was successful but in the end you realize it's more about the journey than the result.
Title: Re: 392PA rebuild
Post by: Psipumper on May 22, 2025, 11:13:49 PM
Now that it's done I feel empty. Of course I'm glad it was successful but in the end you realize it's more about the journey than the result.
I have the same feeling when finishing a project. I sometimes drag them out seems like to keep them going. It is nice to meet your goals in the end and share your thoughts and results here.