Omega232Devils
Well Known Member
I have searched the forums and found some good information, but unfortunately has not corrected my problem. Any additional help is appreciated.
I have been plagued with a tank leak in my quick build tank. (Left one only) I removed the tank about two months ago and did a complete resealing of the inboard rib section that I could get to through the access panel. I was able to clean, prep and re-proseal the inside and outside of the tank. I pressure tested the tank for 36 hours with no leaks (1psi Balloon). Filled the tank with gas and let it sit for 48 hours, no leaks. The tank flew fine for about 2 weeks with no issues. In the meantime I started noticing that my left tank would build up pressure, both in flight and sitting (temperature changes most likely). I found this when I popped the fuel cap and could heard the pressure releasing.
After the two weeks, my tank began developing a small leak in the lower corner closest to the fuselage. (Same spot as the first leak) I pulled the tank off yesterday to do the repair and did the baloon pressure test and soapy water. After 6 hours with pressure, there was no evidence of a leak. (Frustrating) After I cleaned the old proseal off, and prepped the surface for new seal, the balloon was still inflated. When I put the new proseal on, I noticed a small air bubble between the 2nd and 3rd rivet from the back. (I have to admit, I didn't catch it right away, as I just kept adding more proseal trying to cover up the bubble and it kept coming back) The light bulb finally came on, that this is the source of my leak and explains why my tank leaks when I forget to pop the fuel caps and relieve the pressure.
So that is the good news, I have identified my leak and when it is leaking. (Under pressure = leak / No pressure = No leak) So I looked to my vent system. I have never had fuel come out of the vent ports, regardless of level of fuel. I was able to take my air hose and blow air through the vent on the bottom of the fuselage and feel it on the connector going to the wing tank. I was able to blow air through the vent tube on the tank and feel with my finger the air coming out of the tube by the fuel cap. So my vent lines are clear.
So I can seal the leak pretty easily, but until I identify and correct why my tank is pressurizing and not venting, my leak is going to continue to return.
Where do I go from here?
Dan
I have been plagued with a tank leak in my quick build tank. (Left one only) I removed the tank about two months ago and did a complete resealing of the inboard rib section that I could get to through the access panel. I was able to clean, prep and re-proseal the inside and outside of the tank. I pressure tested the tank for 36 hours with no leaks (1psi Balloon). Filled the tank with gas and let it sit for 48 hours, no leaks. The tank flew fine for about 2 weeks with no issues. In the meantime I started noticing that my left tank would build up pressure, both in flight and sitting (temperature changes most likely). I found this when I popped the fuel cap and could heard the pressure releasing.
After the two weeks, my tank began developing a small leak in the lower corner closest to the fuselage. (Same spot as the first leak) I pulled the tank off yesterday to do the repair and did the baloon pressure test and soapy water. After 6 hours with pressure, there was no evidence of a leak. (Frustrating) After I cleaned the old proseal off, and prepped the surface for new seal, the balloon was still inflated. When I put the new proseal on, I noticed a small air bubble between the 2nd and 3rd rivet from the back. (I have to admit, I didn't catch it right away, as I just kept adding more proseal trying to cover up the bubble and it kept coming back) The light bulb finally came on, that this is the source of my leak and explains why my tank leaks when I forget to pop the fuel caps and relieve the pressure.
So that is the good news, I have identified my leak and when it is leaking. (Under pressure = leak / No pressure = No leak) So I looked to my vent system. I have never had fuel come out of the vent ports, regardless of level of fuel. I was able to take my air hose and blow air through the vent on the bottom of the fuselage and feel it on the connector going to the wing tank. I was able to blow air through the vent tube on the tank and feel with my finger the air coming out of the tube by the fuel cap. So my vent lines are clear.
So I can seal the leak pretty easily, but until I identify and correct why my tank is pressurizing and not venting, my leak is going to continue to return.
Where do I go from here?
Dan
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