Fuel leak....

[Gordon H]

Noticed some staining on the frame (near side) and think I've got a fuel leak but after an hour of hunting around under the tank I can't trace it. :scratch:

There's no sign of rust or any holes so I'm guessing it's coming from one of the connections / hoses from the tank. It's somewhere towards the rear, around the hinge - but I can't find it.

No splits or perishing on the hoses.

It is very slight and only noticed it as the bike has been on its stand for over a week (well, it's been raining a lot around here) and hasn't been out.......

Any ideas?

[utopia]

Does your bike have an old style lead/acid battery? If so, its worth making sure its not battery acid causing the staining, particularly if the staining is deep seated. My frame is stained on the left side, from when the alternator was overcharging the battery causing the acid to bubble. Might be worth checking around the battery vent pipe attachment for signs of leakage while you've got the tank up.

[Trent]

Monster tanks are notorious for leaking around the hinge plate.

People use various ways to repair the leaks, but the most common one is brazing around the hinge plate - stops the leak and strengthens the joint so it should never happen again.

Check this post:
http://ukmonster.co.uk/monster/showthread.php?t=22436

[Gordon H]

Does your bike have an old style lead/acid battery? If so, its worth making sure its not battery acid causing the staining, particularly if the staining is deep seated. My frame is stained on the left side, from when the alternator was overcharging the battery causing the acid to bubble. Might be worth checking around the battery vent pipe attachment for signs of leakage while you've got the tank up.

Def not acid - new battery and the staining wipes straight off with no after effects.

Cheers

G

[m900]

Monster tanks are notorious for leaking around the hinge plate.

People use various ways to repair the leaks, but the most common one is brazing around the hinge plate - stops the leak and strengthens the joint so it should never happen again.

Check this post:
http://ukmonster.co.uk/monster/showthread.php?t=22436

i had this hinge leak too. when i picked my monster up i filled it to the brim with petrol. the next day my garage stank of petrol and i didn't have a drop left in the tank.

i bought brazing rods to strengthen. i then covered with a liberal layer of liquid gasket and then quickly a layer of household silicone.

might be a bit of a bodge, but hasn't leaked a drop since.

hello, by-the-way. only my second post, but i have been looking at the forum for a while.

[Capo]

Clean off the area around the hinge then spray some foot powder over the area, if you have a leak it will be visible as the powder darkens.

[Mark Taylor]

I also had a leaky petrol tank, I found an ad in Classic Bike magazine for a chemical resin seal that you pour into the tank and it worked a treat - can't for the life of me remember what it was called! It's been in my tank for 4 or 5 years tho.

[motojohn]

had the same on my S4 did have a go at sealing it on the inside with resin but no luck .
the leak on mine is under the hinge plate on the bottom of the tank ,i sorted mine with chemical metal spread it all around the edges of the hinge plate that stopped it . the best way is to pipe it though a plastic bag a bit like piping a cake , the end product looks like its been welded