In-Frame Gas Tank Frame Leaking

Killa_P_79ish

New Member
Mar 6, 2016
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Riverview, FL
There's what looks like a weeping hole at my front mount stud portion of my frame. Gas has begun leaking out of here. How? Is it coming down downtube somehow (which is only thing that makes sense to me)? I can plug with fuel tank repair or even weld, but HOW is gas getting here is my question? Search high and low for how these are constructed but to no avail.
 

Dan

Staff
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May 25, 2008
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Howdy Killa, Welcome.

If ya wanna post pics, I'll approve them so ya can get some input.

(as an anti-spammer feature. You need to have posted a minimum number of times before freely being able to post pictures and links)
 

Killa_P_79ish

New Member
Mar 6, 2016
4
1
3
Riverview, FL
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Okay. So, emptied tank last night, worked an 8-4 today to come home to it still weeping. The bottom of the two holes between the bolts is where the weeping occurred. I put a splash of gas in tank (tilted bike forward) and it wouldn't budge--if it did, it was VERY slowly. I then decided to drill a very small hole under frame, at mount, and gas started streaming out, and quite a bit of it, and for several minutes. Meanwhile, looking thru gas cap opening, gas still hadn't--apparently anyway--budged. Puzzling. My initial assumption was at the little bead of weld seen when you look through gas cap opening; but, again: the little gas I poured here isn't budging...Or, rather extremely slow. I am going to check on it here shortly
 
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Killa_P_79ish

New Member
Mar 6, 2016
4
1
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Riverview, FL
Culprit is somewhere at front of frame. A lost cause. No way I'm getting to this without cracking open. So, I used some Permatex fuel tank repair puddy, patch all of my 2 drilled holes (did a 2nd further back later to get ALL gas out of down tube) and the holes at base of mount. The. After a complete 24 hrs, slapped on some J.B. Weld for extra measure. I'll fill up tank later and of course it'll fill downtube 1st, bit I'm hoping to after this retain fuel in tank...I'll obviously just forever have fuel in down tube
 

crassius

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Sep 30, 2012
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back in the day, there used to be a gas tank sealant for leaky tanks - we just called it elephant snot due to its look & consistency, but not sure what real name is - worked very well, but tilting and turning your tank to get it to spread all around lower half of tank may be hard when attached to frame
 

Dan

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May 25, 2008
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At least ya have some backup fuel, just in case?

LoL, sorry. Couldn't think of anything actually supportive.

Ya did remind me of a project I kinda forgot about. I wanted to make a tank with alumniweld. (sp) ya heat aluminum and use these sticks to make joints. Stuff is amazingly strong.

https://smile.amazon.com/Harbor-Fre...006ZBASPU/ref=cm_cr_arp_d_product_top?ie=UTF8

Sanded down some practice joints and looked really good, too.
 

Dan

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May 25, 2008
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back in the day, there used to be a gas tank sealant for leaky tanks - we just called it elephant snot due to its look & consistency, but not sure what real name is - worked very well, but tilting and turning your tank to get it to spread all around lower half of tank may be hard when attached to frame
I've used that. Costly but did a good job.

Have some left. Wonder if it's kept. Been a few.

(But thinking that demo build for the grant.)
 

Killa_P_79ish

New Member
Mar 6, 2016
4
1
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Riverview, FL
Interesting. Yea, this "Elephant Snot" is expensive but accessible. Thanks for the input. Off today so I'll fill up tank in a bit and giv'er a whirl. Both Fuel Tank Repair and J.B. Weld should be fully cured for sure! Lol
My only concern now is, if not used frequently enough--just a fun toy for me--will the gas in down tube ultimately stale and effect topend? I can't imagine what's in downtube, at the rate it takes to fill (pinhole), actually circulating thru...?
 

Dan

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May 25, 2008
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Will turn to varnish, dry out. How long depends on how much in comparison to the container.

I would think of it more as an eccentricity of her, rather than a concern. Not gonna do any harm. Like an old carb. It turns to a brown coating that is a PITB to clean but makes a nice seal.
 

Dan

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May 25, 2008
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Will turn to varnish, dry out. How long depends on how much in comparison to the container.

I would think of it more as an eccentricity of her, rather than a concern. Not gonna do any harm. Like an old carb. It turns to a brown coating that is a PITB to clean but makes a nice seal.