Leaking fuel tank repair

[OGGUZZI]

2001 gray lemans fuel tank is leaking old fuel  at the rear edge. Previous owner had made  patch that appeared to be a layer of light colored bondo then a layer of yellow tinged translucent material covering the bondo.  After removing  the patch Im looking for the correct material to clean the area for the new patch and what type of fuel resistant  products to use for the patch.  The area is located behind the hold down bolt on the rear edge and appears  to be a seam from when the tank was formed.   thank you in advance for any help.  Our last MotoGuzzi was a ‘76 850T3 so this is lemans is all new to me.

[gstallons]

I think you will be better to do a repair from the inside of the fuel tank. Wait for others to post their input on what type of fuel tank liner to install and the proper procedure. Yo u will get one chance so do it right !

[Lucky Phil]

4 hours ago, OGGUZZI said:

2001 gray lemans fuel tank is leaking old fuel  at the rear edge. Previous owner had made  patch that appeared to be a layer of light colored bondo then a layer of yellow tinged translucent material covering the bondo.  After removing  the patch Im looking for the correct material to clean the area for the new patch and what type of fuel resistant  products to use for the patch.  The area is located behind the hold down bolt on the rear edge and appears  to be a seam from when the tank was formed.   thank you in advance for any help.  Our last MotoGuzzi was a ‘76 850T3 so this is lemans is all new to me.

We need images. Sounds like Ethanol related sweating to me. have you had the tank off the bike? have you then tried refitting the tank and if so has it swelled?

Phil

[gstallons]

First things first. Use ONLY straight gasoline . No alcohol diluted fuel . If you think it is only sweating (as Phil suspects) remove the tank and let it dry out inside of the tank. It will not hurt to do this over a couple of weeks. Me  personally , I run straight gasoline in everything that is air cooled or off-road .