S4R metal tank: leaky hinge? (pics)

[♣ McKraut ♣]

i'm thinking no... and it's just something that's not forming a perfect seal/fit on the underside of the tank... but i thought before i took it to someone to have it looked at closer i could just post a couple pics up to see if anyone had an opinion

   

   

[♣ McKraut ♣]

and...yes, i have committed the "wrong section" post once again... please feel free to move this into tech 

[Silver King]

I dunno...I'd clean the piss out of it and then try to find the leak.  Maybe the seal around the fuel pump?  Are all of the breather hoses intact?

[redial]

when people lift the tank when its FULL of gas it puts too much stress on the hinge
and the weld cracks. creating a small but steady leak. Im not sure if you are asking what the
problem might be, or just to see if thats what we think it is.

In pic one i cant see much but pic two looks like leaky hinges that i have seen.


you have two options,

1. get someone who knows what they are doing to braze the hinge. I believe ducpainter can do this
ask him. he knows whats up. due to heat it can mess up the paint, but in a spot that would be covered by the
seat, so only you will know.

2. JB WELD! ugly but ive seen it work. i have two friends who both ride DSS monsters and both suffered the leaky hinge. one JB welded himself. The other sent to the local duc dealer and unbelievably they used JB weld too!!!!!    neither bike leaks now, a year later.

[Howie]

Clean the area well, then spray with aerosol foot powder.  The gasoline stain will lead you to the leak.  Yes, it is probably the hinge, but you want to be sure.

[eichh]

That looks exactly like mine did when it leaked. I lifted it up with a full tank one day and it started to leak after that. Never a steady drip or anything but always moist. Since I didnt want my balls to burst into flames one day on a ride I had my buddy TIG weld every seam on the hinge and then had a local radiator shop put that purple rubbery membrane sealant stuff in it. And its been fine since I think its been 3 years or so. You can buy that liner stuff I believe through the Jake Wilson catalog. And since the hinge is now welded properly I can lift the tank with gas in it and have no problems.

Good luck

[♣ McKraut ♣]

sounds like i need to learn how to take a tank off....  it's always something i guess.  would the constant leak of fuel have anything to do with this stain on a valve cover on the vertical cylinder?  or is that just what baked paint looks like due to heat?

[redial]

unfortunately when fuel leaks and then bakes onto the metal engine parts it leaves a yellow stain
that is seemingly impossible to get off



if anyone has a hint on how to clean this please post. my verticle cyclinder is yellowed from an oil leak i had
from not tightening my valve cover properly, and my buddys whole left side of his engine case
is yellowed from the hinge fuel leak from the previous owner *(then he JB welded it, but the stain is stil there)

[Michael]

sounds like i need to learn how to take a tank off.... 

How to Remove the Gas Tank on a Ducati M900 Motorcycle

[beatcat]

i've done a couple with POR15 and so far so good. I'm sure it's no replacement for a good braizing but for 45 bucks for a whole kit, not too bad. plus it makes the inside of the tank look all silvery and new.

[Duck-Stew]

My vote is also a leaky hinge plate which was spot welded to the tank body in like 16 different spots.  When the tank is heavy and it's on the single-sided-tank-stand, it pivots slightly which does crack one or more of those tiny spot welds.

My repair?  Braze & re-coat w/POR15. 


Whatever you do...keep that steel tank.  Those plastic ones just suck...

[muskrat]

reviving an old topic here.
does someone have instructions on brazing a tank hinge?  I'm assuming the prep is very important but I'm not sure what type of product(s) to use for the braze.  Mind you I will have my Dad here helping and he's a mechanical wiz, not me.
Thanks.

[ducpainter]

Burn off the paint and braze all the way around the plate...it's not rocket science. It helps to remove some paint on the top side to prevent additional damage.

Make sure you coat the tank afterward...the braze is reinforcement...

The coating seals the crack.

[muskrat]

got it.  thanks.

[djrashonal]

I've got a POR-15 kit i bought about 4 months ago but never used (due to the fact that my tank was perfectly fine, and my fuel sender was leaking like a MoFo) if you wanna buy it. Otherwise it will sit under the sink until i need it. It never even left the box that it arrived in.

That's another thing to check, do the foot powder thing, because it might be a poor seal on the fuel sender!\

GL