Benjamin 397-392 is it possible to upgrade soldered valve?

Benjamin 397-392 is it possible to upgrade soldered valve?

Joined: February 22nd, 2003, 9:40 am

June 28th, 2012, 1:24 am #1

I got a Benjamin 397 with a pooched valve in a package deal. The treads on the Valve Retaining nut are in bad shape and the original springs are missing.

I have a spare cartridge type valve, would it be possible to remove the soldered section of the old valve and re-install the newer type valve?

I do not want to put much time into getting replacement parts for the old valve as the threads inside are likely just as bad as the retaining nut.

Thanks
Woody
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Joined: June 25th, 2002, 1:34 pm

June 28th, 2012, 2:01 am #2

n/t
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Joined: February 22nd, 2003, 9:40 am

June 28th, 2012, 3:33 am #3

Any tips? Mainly getting the old one out.
There is a small round spot on the bottom of the tube, is that what is holding the valve in?
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Joined: April 12th, 2002, 5:26 am

June 28th, 2012, 6:06 am #4

I got a Benjamin 397 with a pooched valve in a package deal. The treads on the Valve Retaining nut are in bad shape and the original springs are missing.

I have a spare cartridge type valve, would it be possible to remove the soldered section of the old valve and re-install the newer type valve?

I do not want to put much time into getting replacement parts for the old valve as the threads inside are likely just as bad as the retaining nut.

Thanks
Woody
is wrong for the striker when you try to line the new valve up with the old port.
Last edited by classicalgas on June 28th, 2012, 6:06 am, edited 1 time in total.
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Joined: June 25th, 2002, 1:34 pm

June 28th, 2012, 8:47 am #5

Any tips? Mainly getting the old one out.
There is a small round spot on the bottom of the tube, is that what is holding the valve in?
then a 1/2" drill and finish with a 5/8" drill. With most of the old valve body drilled out, it won't take as heat to melt the solder and there's less chance of the barrel coming loose with the valve. Heat with torch until solder runs out back of tube, Do Not bang on anything because all melted solder will fly off. I set the tube under an arbor press with a long tube against what's left of the valve body, heat the tube and gently press the valve body out. Then wrap Emory paper around a shaft and sand out the remaining solder, then resolder any part that needs it. Now drill mounting holes and install new valve. hth
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Joined: July 3rd, 2005, 8:56 pm

July 4th, 2012, 10:08 pm #6

I got a Benjamin 397 with a pooched valve in a package deal. The treads on the Valve Retaining nut are in bad shape and the original springs are missing.

I have a spare cartridge type valve, would it be possible to remove the soldered section of the old valve and re-install the newer type valve?

I do not want to put much time into getting replacement parts for the old valve as the threads inside are likely just as bad as the retaining nut.

Thanks
Woody
I presently have both the new valve, and the old soldered in valve which I unsoldered, in front of me. Here's some dimension differences:

Outside diameters - old valve .769
new valve .771
Old valve has a flat inlet end, and the new one has the typical tapered end which may make the original piston a tad bit too long. A problem to consider.

The body length is the same ( not counting the tapered end on the new one )

The pressure outlet hole on the new one is prox .040 closer to the back end.
This outlet hole must line up with the barrel hole so if you position the whole valve .040" farther forward to line up the transfer holes you would bring the front of the valve even farther forward and then quite likely would have to shorten the piston rod.

Be careful in sanding out the solder after the old valve has been removed. You only have .002 " of pump tube ID to work with.

I agree that it could be done, but with a " whole boat load of work ".
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