Trying to repair my Benjamin 342 - a few questions

[mark71gtx]

My dad loved this pellet rifle (serial number said it was built in the early 70's) and we used to shoot it a lot on the farm.  It has lost all compression, so I am looking to get a new valve for it.  I found one online at pyramid at a reasonable price.  I am missing a pin or something where the pump handle meets the "piston rod" for lack of a better term.  Is it anything special or is it something readily available?  Any help would be appreciated.  I want dad to shoot it again by the end of the year.  Thanks!

[limbshaker]

I rebuilt my 342 several months ago. They are great little guns!

As for the kit or any parts, I'd get a rebuild kit from Mac1 Airguns. His inlet seal and valve seals are better than the kits from Pyramyd. But either will certainly work fine. You will need a valve tool, and it can be bought from Bryan and Associates, and maybe a couple other places I cant remember. It's only about 12 bucks, but of course it comes in the kit from Pyramyd.

The pin that attaches the pump lever to the piston is a hardened metal dowel. You could make one to replace it easily, just make sure you use a good, hard piece of steel. I believe it is known as a "link pin" and is somewhere around 1/8 inch diameter. Mac1 probably sells a replacement.

Be careful not to screw up and drop a punch or similar tool into the valve when working on it. I did, and it messed up the inlet sealing surface, but I managed to fix it.
http://www.gatewaytoairguns.org/GTA/index.php?topic=60527.msg580234#msg580234

Also, if you're inner lead seal doesn't come out easily, just leave it and reuse it. You may do more damage digging it out, and it will most likely be fine to use again anyway.

If you can't come up with a valve tool, give me a shout and you can borrow mine.

[avator]

I recently bought 2 reseal kits from Tim at Mac1 for a couple Crosman 140s and the pin you are talking about came with them so I know he has pins and one might even come with the kit for your gun. I would shoot him a message. He will respond. Or you could even call his shop, I've talked to him a couple times.... nice guy.

[Habanero69er]

Yep, Tim @ Mac-1 Airguns. He steroided my 342 & it shoots hard, especially with heavy ammo. Be sure to remind your dad to put it away with a couple of pumps left in it.

[mark71gtx]

I have already ordered the pyramid kit since it came with the tool I needed.  I am hoping a good cleaning will help it out.  I will then evaluate what needs to be replaced.  Thanks for the help so far. 

[eeler1]

Check this out;



Valve and pump mechanism are the same as the 342, might help you through it.

[mark71gtx]

Thanks for the video!  It was helpful.  My parts should be here the 2nd.  I'll put in the new parts and I guess I will try to make a new pin for the pump lever.

[mark71gtx]

Well, the parts came in and I decided it was too nice of a rifle (and means too much to my family) to make a pin for it, so I ordered a replacement lever assembly from Baker.  I had to break out the dremel and shave off some of the weld on the pin, but it works like a charm.  I put in the new parts and it had a leak where air was escaping down the barrel.  I took it back apart and installed the rubber o ring and it fixed the problem.  I reused the old check valve since the new Teflon one did not impress me.  All in all I would say it was a success and I am certain dad will have a huge smile on his face when I bring it to him.  Thanks for all of your help and input.

[mark71gtx]

By the way, I checked the serial number and it is a 1973 model, which makes it three years older than me!  The real problem with it was the old piston head.  Mine had the one with the hole in the center, which does not come with the kit, but Pyramid sent me the one I needed at no charge.  Once I replaced it, the rifle started pumping air again for the first time in over 20 years.

[Habanero69er]

You still need to get some Secret Sauce from Mac1 to keep it lubed & preserve your gun. It's actually made for MSP airguns.

[Gillman]

I'm currently sitting on four Model 312's, two Model 347's, a 317 pistol, a Blue Streak, a Silver Streak and a C9 Silver Streak. One of the 312's is an old Nickel finish. A rebuild kit is on it's way from Mac-1 for that gun.

312 in Nickel: Currently torn down, I plan on resealing this gun and it is slated for a scout set-up. This gun grouped unbelievably before the seals finally failed. I am really looking forward to this project.

312: Previously resealed by Mac-1 and has a factory peep. Many childhood memories with this gun that set the stage for my pumper addiction. This replaced my 760 as a kid and I never turned back.

312: Another awesome shooter, I plan on upgrading with a factory peep.

312: An awkward gun to pump because it is set up with a Simmons rim fire .22 scope at the breach. Again, awkward to pump but squirrels beware, if you see some guy frolicking around trying to pump this thing up; quickly seek a hollow and hide for a couple of hours.

347: Still like brand new with a Williams peep. "Deadly"

347: Resealed by Mac-1 last year, factory sights, a stone cold killer.

137: Nice clean pistol, will leak down after a couple days. Just got some Mac-1 secret sauce for Christmas and that doesn't help, I'll have her slated for a re-build.

Blue Streak: Rebuilt last year from Mac-1 (Standard Service) Not steroided because I was not overly impressed with the grouping; Williams peep sight equipped. A can killer but not a tact driver.

Silver Streak: Stunning finish and wood. About to receive my IA mount form Mac-1 and is slated for a scout set-up with a Simmons scope.

C9 Silver Streak: Standard factory gun with no bells or whistles and is slated for a Williams Peep Sight from Mac-1. A friend of mine bought a group of firearms from a woman after her husband passed away; this was thrown in. It was mine for $50.00 and is super clean. I have not benched it but it seems to be a great plinker. Will see what happens with the Williams peep.

So, I'm just waiting to find a nice old 342 for a full steroid conversion. It will cost but I'll sleep better at night with this in my inventory.

[avator]

Nice collection.... I know that feeling..
http://www.gatewaytoairguns.org/GTA/index.php?topic=81841.msg782458#msg782458