See the photos. I note that these replacement third-stage pump heads are very similar to those in the Seneca Aspen and Nova Freedom. Ten (10) of them for $5.00 USD with free shipping from China. Other photos show the sealing ring being two-piece - an o-ring and adjacent sleeve. Perhaps these heads would fit our pump rod. Perhaps the seals on these heads could be placed on the original pump head. Does anybody have their gun apart to compare the measurements to those in the photo? 
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Aspen and Freedom: New Third Stage Pump Head Replacement?
- Thread starter monsterpcp
- Start date
I've had mine apart twice, that is exactly where it broke, I'll take 5 of them for 5$ if you order? I'm willing to risk it to fix it! Can you please post a link so the I can order?
Roscodog
Roscodog
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See my last paragraph for ordering information. Today, I ordered these inexpensive piston/pump heads. Beforehand, I opened up my Aspen to measure the pump piston (gun now back together). The third-stage metal piston measured about 5.85mm in diameter at its widest (wider o-ring seals center the piston in the pump tube to eliminate metal to metal contact). I didn't bother to measure the inside diameter of the Aspen pump tube because I assume it is 6mm i.d. I failed to measure the threading that attaches piston to rod, but my eyeball says the threading will agree with the seller's description of the pistons. I suspect this piston size/style is common in many different pumps. I ordered 5 pump (piston) heads: Four pistons from one seller have a spring, like the original in my Seneca Aspen. The fifth was from a different seller, and deletes the spring assembly, but has similar seals. Total cost was $10.00 USD for all five together.
It will take four weeks for the pistons to reach me. I'll report my results after installing same. I have taken some photos towards writing a tutorial. Soon, I hope.
There are many online sellers of these pistons. "Search "piston stage" or "pump stage". It worked for me! If you're in a hurry, Ebay lists a bunch of sellers. If you don't mind waiting for a slow boat from China, there are many sellers at Aliexpress. NOTE: Some sellers featured photos of three, four, or more pistons together, but the fine print clarified that you were buying just one or two pistons for the listed price.
It will take four weeks for the pistons to reach me. I'll report my results after installing same. I have taken some photos towards writing a tutorial. Soon, I hope.
There are many online sellers of these pistons. "Search "piston stage" or "pump stage". It worked for me! If you're in a hurry, Ebay lists a bunch of sellers. If you don't mind waiting for a slow boat from China, there are many sellers at Aliexpress. NOTE: Some sellers featured photos of three, four, or more pistons together, but the fine print clarified that you were buying just one or two pistons for the listed price.
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