Tank seeping on bottom back seam

[nettshubby]

My wifes 620 injection Monster is weeping petrol from the back seam. I noticed it when the tank had been propped up to connect a battery tender. I suspect corrosion inside the tank.

Can anyone tell me which models (Injection) have a tank that fits the 620 Monster, as I would like to obtain a more recent used item. The bike is a 2004 model.

Ray.

[don_matese]

Is it definitely the seam? Mine looked like it was but it was actually from the fuel outlet. It was on a metal m600 tank though

[dunlop0_1]

If it's the metal tank my money is on the where the hinge is spot welded to the tank. I must have welded up half a dozen of these. :)

[utopia]

And I suspect that such leaks may be caused by propping the tank up, on a regular basis, when there's a lot of fuel in it.
The std prop strut fits to one side of the tank only, and this causes it to twist at the rear hinge.
On top of that, the little plastic hook thing on the end of the prop is feeble and can easily break (mine did) bringing the tank crashing down.
So in future, I'd recommend fitting a charging socket somewhere, so the battery can be charged without lifting the tank.
Also, when the tank is lifted, use a suitable piece of wood to prop the tank centrally from the airbox/coil mount instead of the std wire prop.

[Kato]

Try the search facility

http://www.ukmonster.co.uk/monster/search.php?searchid=2118283

[Nickj]

On top of that, the little plastic hook thing on the end of the prop is feeble and can easily break (mine did) bringing the tank crashing down.


I welded a little 'J' bent rod onto the top to replace the broken plastic bit, covered it in plastic. Works for me :)
It isn't recommended to use these with a full tank, it'll still stress the welds a little even if you prop it in the centre as the hinge isn't really that precise and mine always twists a little as it lifts.

[nettshubby]

And I suspect that such leaks may be caused by propping the tank up, on a regular basis, when there's a lot of fuel in it.
The std prop strut fits to one side of the tank only, and this causes it to twist at the rear hinge.
On top of that, the little plastic hook thing on the end of the prop is feeble and can easily break (mine did) bringing the tank crashing down.
So in future, I'd recommend fitting a charging socket somewhere, so the battery can be charged without lifting the tank.
Also, when the tank is lifted, use a suitable piece of wood to prop the tank centrally from the airbox/coil mount instead of the std wire prop.

Actually, the 620 my wife has doesn`t have a prop, so i use a pice of wood between tank and handlebar centre.
As for exactly where the leak is, I`ll have to have a proper poke around after cleaning the underneath.

Ray.

[nettshubby]

Just another thought, is glass fibre resin, and Araldite proof against Ethanol that`s kreeping into petrol these days? I ask because I once made a model aircraft aluminium tank for a glow plug plane and Araldited it together. As soon as I put fuel in it disintrigated! If memory serves the fuel was, or had Ethanol in it?

Ray.

[Dirty]

Just another thought, is glass fibre resin, and Araldite proof against Ethanol that`s kreeping into petrol these days? I ask because I once made a model aircraft aluminium tank for a glow plug plane and Araldited it together. As soon as I put fuel in it disintrigated! If memory serves the fuel was, or had Ethanol in it?

Ray.

The latest Dukes (848/1098/1198) have glass fibre fuel tanks so I presume they must be?

[Darkness]

Try the search facility

http://www.ukmonster.co.uk/monster/search.php?searchid=2118283

Why, does it say the same as your link: 'Sorry - no matches. Please try some different terms.'?????

[stef]

i had two monsters with the same problem.
it is indeed around the spot welded hinge. it's very difficult to locate the exact leak location, petrol has this thing about seeping through the tiniest crack. petrol then runs on the underside, and ends up around the seem.
the solution i used was to thourougly clean the tanks (i used water..maybe someone can recommend something else)
then silver braze around the tank hinge. it's low(er) temperature, so it doesnt damage the paint that much.
then, a rince with corrosion stoping acid (if you used water to clean it)

[utopia]

...corrosion stopping acid ? ....tell me more.

[stef]

...corrosion stopping acid ? ....tell me more.

special mixture (gel formula) i got from Halfords if my memory serves me right.
design to clean and stop rust inside petrol tanks. and i think it was some mild acid.

ill try to get you the reference.
found it:
http://reviews.halfords.com/4028/728576/reviews.htm

[utopia]

Ah, yes.
Thanks for the link.
I had always assumed that such products were for rust removal/neutralisation, rather than subsequent prevention, but knowing the reputation of Hammerite products, I wouldn't be too surprised if this one went further.
I'll check out the blurb on the tin next time I'm in Halfords.

And yes, I seem to remember that silver solder was the repair of choice for such leaks, according to previous threads.

[Geoff Ives]

Here's a tip.
If you are 'out and about' and get a fuel leak from a seam rub a bar of soap into the area to make a good but temorary repair.
This is not a joke, it really works.

[Dirty]

Here's a tip.
If you are 'out and about' and get a fuel leak from a seam rub a bar of soap into the area to make a good but temorary repair.
This is not a joke, it really works.

It's not the repair for me I'm afraid! :chuckle:

[BluprintZ]

This was one of the problems i came across when i was re-building my M900 a few years back, the tank seams at the rear were starting to expand due to the rust build-up inside them.
I spent ages cleaning it down to the metal, then a mate brazed it up for me.
Mine never got to the point of leaking but i was aware that if i didn't sort it out soon, then i would eventually have problems with it, so i took advantage of the bike being stripped and sorted it.

G ; )