I think my fuel tank is leaking... DO NOT USE THIS UNSAFE REPAIR METHOD

[fixingstill]

I was inherited a 1997 20' Marin Runaway that was sitting for about 10 years. Engine seems to run fine with a 2nd fuel tank after replacing the spark plugs, oil, and filters. Now I found out the fuel gauge needle never moved and then the front hull storage area is now filled with fuel. Looks like the aluminum fuel tank under the deck is leaking? The deck needs to be cut out to remove the tank or any way to patch it from inside without removing the tank? Or what would such job cost me if I take it to a shop? Or maybe it is not a tank leak?

Any comment is appreciated. I am a total newbie for this. I was forced into this relationship.

Oh man, I can't post pics yet. Here are the links:

http://www.beyondautomation.com/AIma...625_140311.jpg

http://www.beyondautomation.com/AIma...824_223148.jpg

http://www.beyondautomation.com/AIma...824_212823.jpg

 

[Scott Danforth]

could be fuel tank leaking
could be your fuel hose is leaking and when you filled it filled the front compartment.

there should be an inspection cover over the fuel tank sender at a minimum.

 

[tpenfield]

:welcome:

There should be a center section of floor/deck over the fuel tank (between the 2 seats) that can be removed. Looks like the carpet may have to come up in order to see it though. Maybe take the seats out first and then you could pull the carpet.

You will want to refrain from using power tools or causing sparks until you have remedied the fuel situation . . . so be safe.

 

[Grub54891]

Dang, if it filled the bow area, it's not sitting correctly, it should have been sitting bow up, plug out for drainage. I bet you would have found the leak sooner that way. Regardless, some tanks are sealed under the deck, some have a panel, with the screws hidden in the carpet matting. Poke around with a screwdriver and you may find them. Either way, the tank would have to come out for repair or replacement. if it's the tank that is leaking, no jb weld will hold for long. No power tools till you get all leaked fumes out, very dangerous situation in that regard. Good luck, It can be fixed!

 

[fixingstill]

I took couple more pics to show:

http://www.beyondautomation.com/AImages/20170825_072946.jpg
http://www.beyondautomation.com/AImages/20170825_072850.jpg

The boat is on the driveway tilted downward. Maybe that is why the fuel goes to the front hull instead of under the engine area. The hoses are exposed and no leak on them. When I filled up 5 gallon, the fuel gauge did not even move, so I would assume it all leaked out to the front hull.
The carpet is wall to wall and wrapping around the seat stands. It looks easier if I cut (sharp knife) 2 lines on the carpet, I will be able to see the center section of the floor/deck and hopefully that section can be removed without cutting and it is bolted down by screws.
Once I have the tank out, I will cut out a 1'x2' square at the bottom to see the condition and clean up the corrosion then take to a metal shop to ask them to weld on new pieces to cover the leaking holes and then the 1'x2' square.
What I have no idea is, after putting the tank back, how do I put back the carpet (if not damaged) so that I don't see the cut? Or install some sort of edging to make the center section accessible?

 

[kcassells]

Not rocket science... Cut the carpet and see whats under there. At this point the carpet stinks of fuel anyway. You will end up doing alot more than the carpet to get the smell of fuel out of there.

 

[garbageguy]

Maybe - before you start cutting, verify you have a fuel leak, from somewhere. To start, I would put the plug in, get the boat tilted so the stern is lower than the bow, have a container ready at the plug, pull it, let it drain - for a while. Let the fuel drain as much as possible, then volatile the small amount adhering to the hull. Then do some thorough leak investigation. My .02

 

[tpenfield]

A lot of metal shops won't repair an aluminum tank, particularly if it has extensive corrosion. Some might do it, but they will have to purge the tank of fuel and fumes.

 

[fixingstill]

Maybe - before you start cutting, verify you have a fuel leak, from somewhere. To start, I would put the plug in, get the boat tilted so the stern is lower than the bow, have a container ready at the plug, pull it, let it drain - for a while. Let the fuel drain as much as possible, then volatile the small amount adhering to the hull. Then do some thorough leak investigation. My .02

Confirmed it is from under (or sides) of the tank. I siphoned out all fuel in the hull and then looked for leak while someone was refilling. No leak from the hoses and then the hull is filled with fuel slowly.

 

[fixingstill]

I will cut open the carpet and see. I will update with pics until the boat is ready to go to water.

 

[fixingstill]

Yes, carpet's cut opened and the tank is exposed after removing the plywood.

Yes, all gas leaked out. I am syphoning this out and then the tank.

The ingress hose is big and hard. I could not pull it out. It is soaking WD40. Any trick to take it off? I hate to cut it and spend $ to replace it.

(Yay, they finally let me upload pics.)

 

[Grub54891]

​you need a hose pick, you can get them at most any parts store.

 

[tpenfield]

I usually put an adjustable pliers on the hose at the fitting and twist the hose to break the seal. Then working it back and forth get the hose to inch its way off the fitting.

 

[fixingstill]

Ok. will try getting the hose off tomorrow. Now I want to see if it is cheaper / easier to find a used tank instead of begging shops to repair it. I see the manufacturer is SKYLINE INDUSTRIES in UT 84062 but looks like they are long gone. The model is 48578-00. Anywhere I can look up the specs or I have to do the measurements? I am in San Francisco Bay Area. Any boat junk yard around that can help / quote?

 

[tpenfield]

For cost savings you could go with a plastic tank. Also, some of the larger manufacturers have some standard aluminum tanks that will be close to what you need.

The manufacturers model number would not really mean anything.

It would be best to take measurements of the tank so you can search and compare.

 

[kcassells]

Bummer on the tank. If it is repairable you will be very lucky. But it's worth a shot. Once it's out you can size it up. The tag you show should also say how many gallons it was made for. At least you are moving in the right direction. I ended up getting a decent used tank off ebay.
On another note after you get it out you can see the profile of the tanks bottom. there are different styles. I would try to get the same style so you do not have to modify the existing tank coffin.

 

[fixingstill]

Working on it.
These stainless steel (yet rusted) screws are a pain to remove by hand. Before using an angle grinder, I need to make sure gas is all done, for that, I need to tow the boat back on the level street and tilt it up to soak up all gas I could. Now waiting for the sun to do the work. Then I will cut the screws.
The tank is 23.5" x (45" to 54") and it is 12" height at the center and 9" height on the side. Moeller calls it "Below Deck Boat Fuel Tank" - like their #032552 but too big. I could not find a used aluminum nor a new plastic one that has the same output location.
Thinking about using JB weld (MarineWeld) or Marine-TEX to patch it up. I wil make the tank easily-accessible in case it needs to come out again.

 

[Grub54891]

Never jb or try to patch a fuel tank like that. It WILL fail, at the most inconvenient time, And leave you stranded, or worse, boom. A certified welder, that's willing to work on fuel tanks is an option: not likely to find one though. Replacement is the best route to go. There are places that make custom tanks, I just can't think of who right now.

 

[kcassells]

Patch what? did I miss apic wheres the leak?. Get the tank out and post some pics. Moeller tanks aren't that less expensive than aluminum. And it really doesn't matter till you get it out and see exactly what you have. Yap later after its out.

 

[fixingstill]

The tank is out.

This is the hole:

And there are a lot of other about to go thru:

Chances are it can't be saved, right? And I should not use JB-Weld (too many holes anyway) to patch. So, I am on the hunt for a replacement tank.

The size is:

Any most importantly, the locations and directions of the connections and the sending units need to be exact so that installation is possible and existing hoses can be reused.

How should I look for the replacement tank? Nothing on ebay for used one. Any new plastic one exactly like that (length could be 45" to 54")? Or I need to call around my local boat salvage yard to check?