My right tank drain was leaking, so I went to replace it. Turns out the threads are stripped.
My mechanic said I have two options:
1) Replace the entire tank.
2) Find just the stem from a salvage and replace the stem.
He did mention that he considered intalling a helicoil, but he felt that it would leak around the helicoil. What do you think? If the helicoil is done properly, what are the chances it would leak?
I've already posted on the Trademart for a stem or tank.
Thanks
Rich
Fuel tank drain threads
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
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Fuel tank drain threads
N5740C 1950 'A' Model
- GAHorn
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- Joined: Fri Apr 12, 2002 8:45 pm
Re: Fuel tank drain threads
The sump drain seals against the lower flat surface of the wing stub with an O'ring. If the helicoil-insert is seated deeper than "just" flush... it might work just fine. That's certainly what I'd try.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

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- Posts: 145
- Joined: Sat Feb 25, 2006 2:17 am
Re: Fuel tank drain threads
It turns out that the tank is in worse shape than we originally thought. The baffles are loose.
I did a search and found a tank from CessnaParts.com, at a "reasonable" price, but it says that the original part number: 0523520-1 has been superseeded by #0526007-44.
So, I KNOW that I should be confident that the new number is correct, but I'm not sure. Is there any reason why I shouldn't just go ahead and order the new tank (rather than waiting 4-6 weeks to get the old one re-furbished)?
I did a search and found a tank from CessnaParts.com, at a "reasonable" price, but it says that the original part number: 0523520-1 has been superseeded by #0526007-44.
So, I KNOW that I should be confident that the new number is correct, but I'm not sure. Is there any reason why I shouldn't just go ahead and order the new tank (rather than waiting 4-6 weeks to get the old one re-furbished)?
N5740C 1950 'A' Model
- GAHorn
- Posts: 21302
- Joined: Fri Apr 12, 2002 8:45 pm
Re: Fuel tank drain threads
Cessnaparts.com (Hill Aircraft) is a genuine Cessna distributor. For inventory (and other) reasons, part numbers are changed/superceded. (Cessna numbers their parts based upon engineering drawing numbers, so if a small change in the drawing is made, the part number changes, is just one example.)
If a Cessna distributor is selling you a part they claim is a genuine replacement part for your Cessna... you can probably rest assured it will work just fine. Just make certain they assure you it is complete, and does not need additional items or mods to make it fit (it's an exact replacement) or they'll accept a return with no penalty (and hopefully they'll pay the return freight.
If a Cessna distributor is selling you a part they claim is a genuine replacement part for your Cessna... you can probably rest assured it will work just fine. Just make certain they assure you it is complete, and does not need additional items or mods to make it fit (it's an exact replacement) or they'll accept a return with no penalty (and hopefully they'll pay the return freight.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

-
- Posts: 145
- Joined: Sat Feb 25, 2006 2:17 am
Re: Fuel tank drain threads
Just an update:Iceman07 wrote:It turns out that the tank is in worse shape than we originally thought. The baffles are loose.
I did a search and found a tank from CessnaParts.com, at a "reasonable" price, but it says that the original part number: 0523520-1 has been superseeded by #0526007-44.
So, I KNOW that I should be confident that the new number is correct, but I'm not sure. Is there any reason why I shouldn't just go ahead and order the new tank (rather than waiting 4-6 weeks to get the old one re-furbished)?
The 0526007-44 is NOT a replacement for the original tank. It does not have the fuel gauge flange on the side, and the filler neck is not correct. To make it work would have taken quite a bit of creative welding.
The good (great) news is that Hill Aviation gave me a 100% (including drop fees and shipping costs) refund.
The other good news is that I bought a salvaged tank from Discount Aircraft Salvage that is in great shape and the price was excellent. I'll be back in the air tommorow.
Thanks for all the help.
Rich
N5740C 1950 'A' Model
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