Rebuilding a Vintage Silca Pista Pump

I wanted a little summer project that wouldn’t take me all that long, or cost all that much money. I decided I’d track down an older Silca Pista pump and bring some new life back to it. I tracked one down on ebay that was as complete as I could find, at least with the more important brass bits, without spending over $100 on the thing. Found one with a broken handle that I could work with.

Some of them apparently have manufacture dates stamped onto them, but none of the listings I could find listed the date of manufacture, or showed a picture of the date stamp. I figured I’d buy one, then have to wait and see once I got my hands on it.

0711191638
0711191639

The one I got apparently has no such stamp. It’s definitely got some age on it, but I can’t be certain. I figure it has to be at least mid-1980’s or a little older. Mine looks a decent bit newer than the 1979 pump I linked above. Either way, the modern iteration of Silca still sells a bunch of the parts to maintain these old pumps so I didn’t think it would be any trouble to maintain it.

After lubricating the old leather washer and inspecting the pump, I came up with a parts list that I’d need. I opted not to purchase one of Silca’s rebuild kits since the gauge appeared functional. I also decided to purchase some 3/16″ rubber hose from McMaster Carr instead of the replacement hose Silca sells, because I wanted a slightly longer hose.

0725191758

The existing leather washer was actually in functional shape. I decided to replace it, anyway, because I just wanted to freshen the whole thing up. The rubber seal in the chuck was completely done, though. And the plastic threaded bit above the leather washer you see in the pic above, apparently has a tendency to crack, so I decided to replace it with stainless hardware now and stay ahead of it. I also wanted a bit more flexibility with chucks, so I got a threaded schraeder chuck to go on the end of the hose. I’ve had a Silca disc wheel presta chuck for quite some time that I could just thread onto it.

0725191757

First step was the plunger parts swap. I had to condition the new leather washer with the lube. It’s similar in texture to Phil Wood Tenacious Oil, but a touch lighter, for reference.

Removing the old parts required a 17mm socket or wrench. The hardware kit Silca sells includes washers for both sizes of leather washers (and pump barrels), so use the appropriate washer for your pump. You’ll note that I’m using the 731 leather washer, and therefore used the thick washer.

0725192127
0725192138
0725192138a

To remove the barrel from the base and the gauge/valve assembly, you’ll need a 5mm hex key to remove these two bolts from the underside of the base.

0726191551

There’s a tiny little o-ring between the barrel and the valve assembly. It’ll probably be stuck to one of the parts, but be careful not to lose this little thing. You should probably inspect it to make sure it’s still pliable and will seal. Silca doesn’t sell this part, but you can probably find a replacement at a hardware store. I gave these parts all good cleanings while I had them disassembled.

0725192213a

While you’ve got everything apart, you might as well clean/inspect the check valve. It’s inside the brass housing here (what I’m calling the valve assembly), and is accessed by removing the brass nut at the end. This requires a 12mm wrench. I actually did this step last, because once I reassembled my pump and tested it on a tire, the pressure in the tire would cause the pump handle to rise. Something was preventing the check valve from closing properly. Inspecting and cleaning the check valve now will give you the chance to order a new one if this turns out to be necessary.

0725192211
0726191449

Once you’ve got the valve out, clean and inspect the spring, the end of the valve, and the rubber o-ring near the tip. You should be able to just pull it out of the cap, but there will be a little resistance, especially if there’s crud buildup. It might also be useful to use the blow gun attachment of your air compressor to clear any debris out of the housing. Using a flashlight to look inside can help you figure out if there’s any debris you missed. When finished, reassemble.

My pump had the reversible chuck, so I needed the 323 elastomer seal for replacement. At this point, I pried the old, crusty one out with a small screwdriver and fit the new one, even though I’m not reinstalling this chuck.

0726191514

I didn’t take pics of this step, but I had to cut the old, stiff hose off with a utility knife, since it wouldn’t pull off of the barbs. The hose clamps I have just require pliers, and I decided to reuse them on the new hose. I pressed the hose onto the pump valve assembly fitting, as well as pressed the threaded schraeder chuck onto the free end. I refit the hose clamps and installed my disc wheel chuck, aka, “crackpipe.”

0726191511a

I still have the old, broken handle on it since I haven’t figured out what I’m going to use as a replacement yet. I’ll probably make a wooden handle. Silca also doesn’t have replacement handles for sale, though I did find an exact replacement handle for sale on ebay. I just think $26 for the handle plus $3 shipping is steep for a lump of old plastic. My broken handle works fine for now until I work something out.

You’ll also notice in the picture above that the chuck is sticking to the pump barrel. I’m using a small rare earth magnet that I had sitting in my toolbox. The magnet won’t stick to the base (apparently cast aluminum), the threaded schraeder chuck (stainless steel), or to the presta chuck (aluminum), so all I’ve got is the hose clamp. But it’s enough magnetic steel to work.

This old Silca Pista pump works well now. It’s going to wind up being one of the pumps that I travel with. I have 3 floor pumps right now. One lives in the garage full time. Another lives in my camper. I’ll probably put one in my car, too. I think this old Silca will wind up being my camper pump, simply because the base allows it to store more easily/compactly. The one that has been in my camper will probably be moved to my car, since it’s a pretty cheap pump that I don’t care much about.

For what it’s worth, I can’t really tell how accurate the gauge on this pump is. It seems fine. But the outer gradations on the gauge use bars, and the inner uses psi. Since I primarily use psi for my pressures, and since I’m also dealing with very low pressures on most of my bikes (below 20psi on all of the mtb’s, and below 10psi on my fatbike), it’s hard to tell exactly what the gauge is telling me. I use 30psi Meiser accu-gages to give pressure readings, anyway.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.