Taipan Veteran slow leak through the barrel
- Thread starter Thach2264
- Start date
Have you tried contacting taipan through their website? Check it out, I think I recall an agn member saying they got parts that way. The contact info is on the website
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No problem...I'm rewriting a portion of it and reordering the steps since it looks like the face of your valve would benefit from being lapped.
- Lap the poppet to the valve face - Apply a mild abrasive* to the poppet and insert the stem into the valve. Grab the exposed stem and spin it in the valve to help smooth out the rough machining marks in the brass. Refresh the abrasive often and take care not to let heat build up too much that it would soften or melt the poppet.
- Check your progress - After you've lapped the parts together a bit, clean off the abrasive and use a black marker to color both surfaces. Reapply some compound and spin the parts together again for a short time. Clean again and inspect both surfaces with the aid of magnification and good lighting. When the brass valve face has the black marker worn away in a clean, continuous ring, set it aside and inspect the poppet face. If it too has the black worn away neatly, you can move on with a final smoothing pass using a lighter abrasive. However if the poppet still needs to be worked down some more, decide if you want to continue with the lapping compound or finish surfacing it using the wood jig pictured in the next step.
- Optional jig for surfacing the poppet - Make a simple jig by drilling a hole in piece of scrap wood just big enough to accept the stem with a slip fit. Then prep a piece of sandpaper by using a hollow punch or leather punch to knock a series of holes in it.
Note the hole was drilled with a drill press so it's nicely perpendicular to the wood's surface. This aspect is not absolutely required. If the hole is slightly angled, you can still successfully lap the poppet, it will just develop a slight convex taper to it which is actually advantageous for sealing.
- Dressing the poppet face - Pass the poppet through the paper and through the wood, and grab the stem with a handheld drill and pull against the sandpaper while spinning it. As before, use discretion not to overheat the plastic poppet.
- Check your progress - As before, color the poppet with a marker and check occasionally to see when the marker has worn away in a clean, continuous ring. If you needed coarse paper to get to this point, you'll want to progress through some finer grits to achieve a higher quality surface finish. 400 or maybe 600 grit is probably as fine as you would need to go with what appears to be Delrin / acetal.
- Final lapping pass - To ensure the poppet and valve are nicely mated, do a final brief pass where you lap them together with a light abrasive. For this step, a polishing compound or J-B will do nicely.
Put my order for a new poppet and face valve through TalonTunes.
I don't like to said that someone dump on me, he did sent me a working gun. Just after I remove the PP, the air leak. I was surprise about the face valve too though.
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@nervoustrig , most excellent contribution and solution!! You contribute so many good ideas in your posts. There needs to be a way of reporting positive solutions for posts like this other than plain likes.
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@Thach2264 ,
Another interim solution occurred to me....clean the sealing surfaces with rubbing alcohol or orange oil as previously mentioned. Beware of strong solvents that might attack the plastic though.
Soak the valve in hot or boiling water a few minutes to soften the plastic.
Then apply a light film of silicon grease to the sealing surfaces and reassemble. The grease may allow you to air up the reservoir. If it holds, let it sit for a day or two while the full reservoir air pressure forces the valve against the body and molds the sealing surfaces together.
This might get you shooting again until you get new parts. It will take a few shots to blow the grease residue out and then run a few patches through the barrel. The silicone may help season the barrel.
Feinwerk
Another interim solution occurred to me....clean the sealing surfaces with rubbing alcohol or orange oil as previously mentioned. Beware of strong solvents that might attack the plastic though.
Soak the valve in hot or boiling water a few minutes to soften the plastic.
Then apply a light film of silicon grease to the sealing surfaces and reassemble. The grease may allow you to air up the reservoir. If it holds, let it sit for a day or two while the full reservoir air pressure forces the valve against the body and molds the sealing surfaces together.
This might get you shooting again until you get new parts. It will take a few shots to blow the grease residue out and then run a few patches through the barrel. The silicone may help season the barrel.
Feinwerk
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I did use some rubbing alcohol to clean. Currently, I can still fill the gun all the way up to 250b, but it slowly leak overnight. It did some for strange reason stop leaking once it fall to around 200b. I tried filling up again to 250 thinking it'll hold, but again it slowly leak down to around 200b beforeit stop leaking. My new parts should be here today and will swap it all out.
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That is a symptom of an O-ring that is borderline extruding. When the pressure is high, it extrudes into the gap and air escapes slowly. Eventually the pressure falls enough that the O-ring relaxes and seals and the leaking stops.
So as bad as the poppet and valve seat appear to be, they may have had nothing to do with the leak after all.
Degas and disassemble and look for an O-ring that has thinned out around its perimeter. An example:
I agree with Nervoustrig, your poppet sealed. Your high pressure leak is elsewhere. Just reseal the whole gun after seeing what the previous owner did.
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Well, I tried just the oring last night but it still leaks down to around 170b, dry fire a few time ( refill back up to 250b) to try to get whatever needed to be seal but it's a no go. This morning, swap out the valve and poppet and instantly with the balloon test. NO LEAK!!! And as a bonus, what better way to enjoy it to shoot it with your own made resin magazines. Cycles flawlessly!!!
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Congratulations fixing it yourself. So the reservoir is no longer leaking down or just no more poppet valve leak through the barrel?
You might have to make a soap solution and brush it on a few places to find the leak if that is still a problem.
Have fun with it.
Feinwerk
You might have to make a soap solution and brush it on a few places to find the leak if that is still a problem.
Have fun with it.
Feinwerk
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The reservoir have no issue, not sure which once cause it to leak through the barrel so I replaced both the poppet and valve face (had been work on).
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