Removing the fuel tank.....

[roamak]

So looks like Im going to be pulling the right wing tank due to some leaking fuel I cant seem to track down. Any advise on steps to take? What to replace when out? For a while I thought it was the drain plug fuel sump leaking but today I see its coming from above that someplace. Only seems to be wet when completely full.
Any tips and tricks?
Greg

ps. Also this tank seems to be different than the other side as the sump drain takes a different part number. Anyone run into this before?

[bagarre]

Greg,

Do a search on Fuel Tank Removal. There is a good bit of information on this site about it.
I have a slide deck given to me by Jim Wildharber of this site on tank removal and repair.
It's got a lot of great info in it and is on my todo list.

ping me at n2481d at gmail dot com and I'll pass it along to you.

-David

[Bruce Fenstermacher]

Greg has a 53 B model.

Sumps drains should be the same left and right.

[tdukerich]

Looking foward to replies. We have a right tank that leaks when full. Take out 5 gallons and most of time time it will stop. There are times when it keeps on weeping somewhere.

170B '52

Tom

[roamak]

Thanks for the replies. bagarre, Im not sure what a slide deck is...but if I need it then I need it. Will look into that. I do have a 53 B model and I always figured the sumps were the same, until today when I tried to screw in a CAV-170 sump drain in a hole that a CAV-160 came out of. I just love that $6 per gallon av gas flavored deodorant running down my arm...
Another thought that just hit me is this started recently.(last month or two) This winter we pulled the fuel caps and re-indexed them. Sealed with pro-seal. The very slow curing seal. Now I wonder if that side didnt seal and is leaking maybe? Or the gaskets got messed up perhaps.
I did a search and there is very good info here. If anyone has a clue on the different sumps, I would like to hear that. From what I can find, the CAV-160 is used on piper aircraft. Nothing on cessnas. Will have to do some research on that....
Greg

[blueldr]

If I remember correctly, the original fuel sump drain bosses used machine threads. I have seen what apparently was a repair job where the boss was tapped out using a pipe thread. I do not believe there is enough material in the boss to accomodate the next larger size of machine thread in he event the threads in the boss are stripped.

[Bruce Fenstermacher]

CAV-170. Description: VALVE, Fuel Drain, 7/16"-20
CAV-160. Description: VALVE, Fuel Drain, 1/4-18 NPT

You should have two CAV-170 valves. Someone jammed a CAV-160 in the boss. I'd look at this close and repair as necessary. If the 1/4-18 NPT threads look ok and it doesn't leak, your probably stuck with that valve.

[Kyle]

Greg,

I pulled mine last year and would be happy to walk you through it. I'll send you a PM with all my contact info.

Kyle T.

[Bruce Fenstermacher]

New gaskets are easy to make locally out of gasket material that can be found at NAPA among other places. I have made and uploaded templates to be copied so you can make the gaskets and be satisfied with the results before you remove the tank.

http://www.cessna170.com/forums/viewtop ... ff076e6f26

[Kyle]

I used Bruce's templates last year and they worked slick

[GAHorn]

Jim Wildharber created a PowerPoint when he did this. I'll bet he'll email it to you if you contact him. (see the directory, and/or via this forums to "jwild".

[bagarre]

Jim Wildharber created a PowerPoint when he did this. I'll bet he'll email it to you if you contact him. (see the directory, and/or via this forums to "jwild".

This is the slide deck I mentioned earlier. It is a very informative deck and walks you thru the process nicely.

[roamak]

Thanks Bruce for the template. I will make some new gaskets even if it turns out not to be the problem. I really have to look into the two different drain valves. Thats not good.
Greg

[Bruce Fenstermacher]

I've had Jim's powerpoint for a few months now with the intent to post it in the maintenance library. Guess now would be as good a time as any.


Here you go. http://www.cessna170.org/forums/viewtop ... 41&t=10345

[roamak]

Aryana please keep us posted on your project. looks like we have the same issue. So the cover screws are the ones that give trouble? I will get them soaking asap. This winter we re-indexed my fuel caps to point into the wind, and re sealed with pro seal. It was a old can and the very slow curing type. We did not replace the gaskets at the time, and I'm really hoping that's my problem. I cant see any fuel around the filler neck but it may be seeping through the gaskets. I have Bruce's gasket template and will start there.
FWIW aircraft spruce has pro seal in a tube. Looks like enough to do a side so you wont have to buy a full can. Anyone know what the cure number is on the tube?
Greg