Silca Impero Problem
01-15-20, 05:29 AM
#1
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Silca Impero Pump Problem
I have a Silca Impero dilemma. It should be easy with the simplicity of this pump but, here goes. And I google searched this to death. Old pump, new oiled softened leather piston. It pumps/pushes air out, but when connected to tire valve, on the reverse stroke, no air pulls in, and suction is created so the handle wants to spring back down. How does air flow into the chamber? Is it supposed to flow around the piston when pulled back? Ideas welcome. D'Ohhh!!!
Last edited by xetaprime; 01-15-20 at 05:54 AM.
01-15-20, 07:11 AM
#2
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xetaprime I would make sure the leather is oriented correctly. I have had them fold part way around making them useless. Cup should be pointed toward the head. The pressure seals the leather against the cylinder to pump the tire. On the return stroke, the leather should let the air go by it and the cylinder. Oh and it should be lubed with appropriate grease for leather.
Take it apart and show us the assembly of the leather.
Take it apart and show us the assembly of the leather.
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01-15-20, 09:44 AM
#3
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xetaprime I would make sure the leather is oriented correctly. I have had them fold part way around making them useless. Cup should be pointed toward the head. The pressure seals the leather against the cylinder to pump the tire. On the return stroke, the leather should let the air go by it and the cylinder. Oh and it should be lubed with appropriate grease for leather.
Take it apart and show us the assembly of the leather.
Take it apart and show us the assembly of the leather.
01-15-20, 10:09 AM
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too good a seal.
01-15-20, 11:05 AM
#5
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Pushing the head too far onto the value and it's holding the valve open?
01-15-20, 11:19 AM
#6
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UPDATE: Old leather piston works fine.
Last edited by xetaprime; 01-15-20 at 11:27 AM.
01-15-20, 11:29 AM
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The problem lies in the leather seal. Its too tight of a fit.They come in 2 different sizes. Or you put a floor pump seal in it.
Last edited by Manny66; 01-15-20 at 11:33 AM.
01-15-20, 11:32 AM
#8
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01-15-20, 11:55 AM
#9
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On Silca website they have 741 - 30mm inside diameter, and 721 - 28mm. I guess those are floor pumps. My caliper is showing 20mm at the threads... why is it never simple?
01-15-20, 12:23 PM
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I always clean the inside of the body, they get pretty nasty. Then relube it separately, sparingly and thoroughly working the lube in before installing the handle and plunger.
I have always used mineral oil which I have seen indicated many times, sparingly on the leather.
