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PostPosted: Tue Nov 08, 2022 3:00 pm 
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Joined: Tue Oct 18, 2011 12:21 pm
Posts: 531
Location: Ontario
When I checked if all my PCP airguns were holding air, I discovered that one of my two Crosman 1701P Silhouette pistols had its pressure gauge showing zero.

Connecting it to my Xisico compressor quickly confirmed that there was something wrong because the pressure didn’t build up and I thought that I could hear air hissing through the barrel.

Since the compressor is noisy, I also tried my Bull handpump so I could hear better and, at some point, I got a pressure buildup. My hope was short-lived because as soon as I dry fired the airgun I lost it all.

I should have stopped there but I tried pumping quicker to see if I could get another pressure buildup. It didn’t work and suddenly I heard a popping sound which made me think that I might have blown out an o-ring in my handpump. Oh well! Another thing to put on the repair list.

Except for the diagram and part list for the Silhouette, I couldn’t find specific information on its disassembly/reassembly but I was told by other members of the CAF that it should be similar to a Marauder.

Having worked earlier on a QB Chief during the Summer and after watching a few videos about the Marauder, I could see that it wouldn’t be a problem to take it apart. Even then I did just the minimum of disassembly required to access the valve.

Basically it breaks down into three sub-assemblies: the Barrel/Breech, the Pressure Cylinder and the Pistol Grip/Trigger. At this point, only the Pressure cylinder needs further disassembly.

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After removing the Filling Plug and the Pressure Gauge, the three screws are detached from the valve body and both parts left in the tube (the Valve and the Port Gauge Body) cand be pushed out toward the front. Once the Valve was separated into the Valve Body and the Valve Cap, a spring and the Valve Stem fell out. Inspection showed that both the internal o-rings on the Valve Cap were in good shape and it was easy to pinpoint the leaking problem because I could see that the molded head of the stem was broken. There was enough left of it to take some measurements and I machined a new Valve Stem from Delrin.

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This is a picture of the components before reassembly.

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I warmed up the Valve Body and the head of the Valve Stem, smacked the head a few times to seat it and applied a bit of silicone grease only. After reassembly the Silhouette pistol was holding its pressure. Another repair has been completed.

R-Gun Pete


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