nut on gas tank w/pics

[dondi]

1985 16 ft thundercraft i o 140 hp screw on top of gas take turns then binds, only about 3 threads come out, i am afraid to strip it, or break it. anyone have any suggestion?trying to check screen on pickup line inside. well now it wont screw out or in, it turns and is still tight fit. i hope it wont leak sorry i started to take her out.

 

[gozierdt]

Re: nut on gas tank w/pics

Get a commercial penetrating oil like Liquid Wrench, even WD-40 isn't bad. Put it on the threads once or twice a day for a couple of days. Try and get the fitting to start moving by going back and forth a small amount with your wrench. If it doesn't move, put some more of the oil on and wait. Usually, after a couple of days, you'll be able to get it to start moving. Then keep putting oil on it while you're working on it, and back it out 2 steps, back in 1 step, until it's out. A common suggestion is to use heat on the joint, but I wouldn't advise it on a gas tank... The fact you're having this problem suggests there may be some corrosion in the tank. A a minimum, make sure you have a good filter between the tank and the engine before starting to use it again.

 

[royal0014]

Re: nut on gas tank w/pics

^ x2 ^


<<)))(((>>

 

[tpenfield]

Re: nut on gas tank w/pics

I assume that is the fuel pickup that we are seeing in the picture . . . Usually, the pickup is welded into the tank and the elbow fitting is what screws in . . . so if you are trying to get the fitting out then OK. If the whole pickup tube seems to be fastened in versus welded in, then you are gonna need to remove it if it is loos and repair/replace it.

Usually, you can get a good look at the fuel pick up by taking out the fuel sender, so long as it is in the same area. since you already started the loosen the fuel pickup and/or fitting, the 'can of worms' is now open.

CAUTION is the word since you are working with a fuel tank. No flames, sparks, heat sources, etc.

 

[dondi]

Re: nut on gas tank w/pics

I assume that is the fuel pickup that we are seeing in the picture . . . Usually, the pickup is welded into the tank and the elbow fitting is what screws in . . . so if you are trying to get the fitting out then OK. If the whole pickup tube seems to be fastened in versus welded in, then you are gonna need to remove it if it is loos and repair/replace it.

Usually, you can get a good look at the fuel pick up by taking out the fuel sender, so long as it is in the same area. since you already started the loosen the fuel pickup and/or fitting, the 'can of worms' is now open.

CAUTION is the word since you are working with a fuel tank. No flames, sparks, heat sources, etc.

thanks for the sugestions i should have made it more clear the gas tank is poly/plastic the sdrew is metal i think ,not sure if oiling it will woerk on plastic but i will give it a try,my worry is if i strip it how do i get the tank out to replace ? take the top portion off the boat, or cut it out?

 

[gozierdt]

Re: nut on gas tank w/pics

OK, if the tank is plastic, the situation is different. It's almost impossible for the metal threads
to bond/corrode to the plastic to prevent the fuel pickup from being removed. So you may have
something else going on, like an angled pickup tube turning with the external pickup fitting, and
hanging up . As Ted said, I think you need to try and get an angled mirror down into the fuel
sender or fuel fill hole and try and see exactly what's going on to hang the fuel fitting up from
turning.

If you want suggestions for removing the tank, you'll have to get us some more pictures of
the bow area under the dash. How deep is the tank compared to the opening between the
bottom of the dash and the floor, etc.

 

[cr2k]

Re: nut on gas tank w/pics

Probably not a nut but a fitting that is either "welded" or flanged into the tank and not ment to be removed.

 

[dondi]

Re: nut on gas tank w/pics

OK, if the tank is plastic, the situation is different. It's almost impossible for the metal threads
to bond/corrode to the plastic to prevent the fuel pickup from being removed. So you may have
something else going on, like an angled pickup tube turning with the external pickup fitting, and
hanging up . As Ted said, I think you need to try and get an angled mirror down into the fuel
sender or fuel fill hole and try and see exactly what's going on to hang the fuel fitting up from
turning.

If you want suggestions for removing the tank, you'll have to get us some more pictures of
the bow area under the dash. How deep is the tank compared to the opening between the
bottom of the dash and the floor, etc.

you guys rock, thanks i picked up that mirror today. its too hot today, so i am waiting till later this evening, to take a look. thanks again, will post progress

 

[Chris1956]

Re: nut on gas tank w/pics

I think the metal "nut" is not meant to be removed. Does the fuel pickup turn inside the "nut"? If so, it may be pressed in, like on my plastic Moeller fuel tank.

I bought the Moeller Fuel tank as a replacement for a old steel tank. I needed to swap the vent and the fuel pickup for my installation. The vent unscrewed, but the fuel pickup was pressed in. I ended up drilling it out and tapping the "nut", so I could install the threaded vent fitting. I used another threaded fuel pickup fitting and screwed it into the original vent fitting.

 

[dondi]

Re: nut on gas tank w/pics

I think the metal "nut" is not meant to be removed. Does the fuel pickup turn inside the "nut"? If so, it may be pressed in, like on my plastic Moeller fuel tank.

I bought the Moeller Fuel tank as a replacement for a old steel tank. I needed to swap the vent and the fuel pickup for my installation. The vent unscrewed, but the fuel pickup was pressed in. I ended up drilling it out and tapping the "nut", so I could install the threaded vent fitting. I used another threaded fuel pickup fitting and screwed it into the original vent fitting.

screw has come out about 3 threads but now it wont go in or out it just turns.think its stripped, metal screw and plastic no match. will let you know if filler turns with it after i insert the mirror later tonight. thanks for the help

 

[dondi]

Re: nut on gas tank w/pics

ok i looked inside the tank with a mirror the fuel pickup does not turn when trying to unscrew the bolt/nut. also inside the tank is a block shaped item. i think it my be the end of a float?one i took out looks new. lots of dirty stuff in there.going to put a filter inline at top of tank, and hope for the best.

 

[Thalasso]

Re: nut on gas tank w/pics

I have air bubbles in my fuel and I am also trying to remove Moeller pick up by clamping big nut with clamping plyers. The elbow is 3/4 inch square and used 15/16 12 point to move it some. I need 7\8 8 point socket, but can't find one yet in Miami florida. I may have to order socket on line. using fluid and allowing time for it to soak in. I too moved the big nut first using 32 mm socket and I am not sure if I messed up the factory seal as it appears to be pressed in fitting. If all fails I will replace the tank. I have replaced sole plate and stringers on this boat and can do the work if needed. I would love to know best socket to use on this square elbow fitting to get a good bite. I see Moeller pick up tube and elbow on iboats similar to mine and good tech notes on Moeller web site, but not enough details to answer all my questions without contacting Moeller about the tank pick up details and insure I have now leaks when I fill up the tank.

You might want to start your own thread. Probably get more response than addressing an old thread for a diff. problem