Fuel caps on 48 rag wing

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air2600v
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Joined: Mon Oct 14, 2002 3:57 am

Fuel caps on 48 rag wing

Post by air2600v »

Three years ago I restored my 1948 170. I recovered the wings and when I did so I put new gaskets on both right and left caps, both on the shaft and around the out side. The out side is of cork and now they leak bad!!!! Is there any other cap I can use that has a better seal? I was told that people have put a flush cap and housing of of a 182 on. The holes that hold the ring on the curent cap system will line up with the 182 System and put pro seal on the aluminum housing and put screws back in and no more leaks. If any one has any info it would be greatly appreciated Thanks Rodney[/b]
zero.one.victor
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Post by zero.one.victor »

On mine, the cap-to-tank gasket is a B.A.O.R.-- aka big a** o-ring. Works fine. Don't know the diameter but that's easy to measure.

Eric
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3958v
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Post by 3958v »

I saw a guy at the Kalispell convention who had what I believe were the Monarch Umbrella style caps. But I dont think there was an STC available. My caps have a large rubber gasket on the outside surface. I added an extra flat washer on the inside which helped tighten things up quite a bit. If you do get water in your tanks use extreme caution. The water can get in the outer tank and there is no drain in those tanks. The drains in the inner tanks could be located better too. I learned all this from the school of hard knocks. I was on a cross country flight from SC to PA when the old engine decided it did not want to run on water. I had drained water from the tanks twice before departing SC. But there was enough water left in there to stop the engine. Fortunautly there was a 1400' grass runway within gliding distance. 1400 ft is real short with no power. I ended up real high but with a real steep bank and full opposite rudder a ragwing can really come down fast. So if you find water in your tanks be real carefull. Bill K.
Polished 48 170 Cat 22 JD 620 & Pug
markhanten
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Post by markhanten »

Mine (3943V) leaks water into the gas tanks after a good rain too. I was none to thrilled to drain a couple of pints (or more) water out of the tanks after a hard rain and it is hard to get it all out. I'm working on the Big A** O-Ring option. Is that how you finally resolved your problem? Any help would be greatly appreciated.

Mark
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tshort
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Post by tshort »

I saw a guy at OSH with a ragwing who had two tarps about 2' wide and long enough to fit over the LE and down over the TE of the wing. He held them on with bungees underneath and used them when parked outside.

I rarely if ever park my ragwing where it will get rained on, but will likely just do something like this if the need arises. The caps I have would definitely leak water - even with a good seal the fact that they are recessed and would allow water to pool would likely cause a leak.

T.
Thomas Short
1948 C170 N3949V
RV-8 wings in progress
Indianapolis (KUMP)
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n3833v
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Post by n3833v »

Sometimes the oring on the shaft is what leaks. I haven't had a problem since I replaced the orings and tightened the outer gasket.

John
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CBogle
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Gas Cap Gaskets

Post by CBogle »

A couple ofyears ago, I purchased two 1948 gas cap gaskets from Yingling Aviation, their item number 0322551. These gaskets came with an FAA/Cessan Authorized Release Certificate which is the airworthiness approval for these rubber gaskets. Two of them cost $125, not cheap. This can't be a hard part to cut out of any standard rubber gasket material and I think that is the option I'd go with next time. No complaint with the approved gaskets but definately not worth the cost and in my opinion, would not be an item that would pose any danger fabricating.

So far I haven't had any trouble with water in the tanks when the plane is left outside on a trip when it rains. But, most of the time the plane is in the hangar. My center o-rings are fairly new also so I'm sure this helps.

Regards,

Curt
markhanten
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Post by markhanten »

Wow! Those guys at Yingling must have thought it was a government contract. Thanks everyone for the input. My mechanic is working on some thicker gasket material and I'll look into new O-rings for the inner seal too. We're also looking into fabricating some covers to keep the rain completely off the caps. With the caps being recessed, even good gaskets are eventually going to let some water in...

Thanks again.
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