top123

My Feedback: (2)

I seem to have problems with a simple issue on plastic fuel tanks. Getting the stopper to seal. Seem to have problems the first time and never get them to seal after having fuel in them. Also have issues with brass tubing sealing in the stoppers. Is the answer to use some silicon sealers or something?

Top

The Ghost

The bolt that goes through the center of the stopper has to be done up tight to seal the tanks.

Cheers

MinnFlyer

My Feedback: (4)

Tighten the screw until you can no longer turn the stopper in the hole, then maybe 1/2 turn more of the screw. Don't crank it too tight or you can split the seam in the tank. (Found that out the hard way many years ago)

ROBT4

I had the same problem and my receiver and srvo connections got saturated with fuel.Is my receiver and servoes still realiable? Thanks

MinnFlyer

My Feedback: (4)

ROBT4, I would suggest asking that question in the "Radios" forum

Ed_Moorman

My Feedback: (1)

I did some fuel tank tests on the generic tanks that come in ARFs built in the far east. This came about because a buddy had a stopper come out on his UCD, soaking the insides of the plane. I also found the stopper out of the tank in my profile Taco which had been hanging in the ceiling of my garage for a couple of months. Third, the stopper came out inside my favorite Heckler 3D plane, ruining the fuselage. Grrrr.

I took an unused ARF tank with stock hardware and assembled it in the normal manner. The screw was fairly tight, not so much that I was afraid of splitting the tank neck, but reasonably tight. I found I could easily push the stopper out with my thumbs. Even after tightening the center screw extremely tight, I could still get the stopper out. This is really bad, in my opinion.

I grabbed both a DuBro and a Sullivan tank and tried them. Couldn't get the stoppers out. Then I made a close inspection of the design and the hardware. Both the DuBro and Sullican tanks have a deeper lip on the tank opening and a cap rather than a flat disc for the outside piece. With the deep lip and the cap, you can really cinch the screw down and the cap helps prevent the tank opening from splitting.

In addition, the DuBro (black) and Sullivan (white) rubber stoppers are much softer than the ARF stoppers. This lets it expand inside the tank easier and grip the neck better. I tried these 2 stoppers. on the ARF tank. It is still possible to push the stopper out, but it takes several tries.

The bottom line for me is: Buy DuBro or Sullivan replacement tank fittings, toss the ARF rubber and use these.

Finally, I also run a bead of Zap-A-Dap-A-Goo around the rubber stopper before shoving it into the tank, effectively gluing the stopper in.

I reported this in the Engine Forum here on RCU and also in my column in R/C Report magazine.

Geistware

My Feedback: (16)

I would coat the stopper with dish soap and install.
Tighten the screw very tight but not over tight.
You can split the tank.
The soap will help seal it.
Never had a problem with this when I flew glow engines.

ROBT4

Thanks Minnflyer.I reposted it in radio mfg direct support.

mscic-RCU

My Feedback: (6)

Toss the ARF tanks and fittings and go get a Sullivan or DuBro tank. Always want to use a seamless tank. I have had too many ARF tanks split at the stopper, the last one on my Hangar 9 Corsair.