Originally Posted by cliffordbigredog
Hi I have a question about repairing a fuel tank made from aluminum with fiber glass resin and glass cloth, how well will it hold up against diesel fuel ?
136 gal. tank in a greyhound MCI bus / RV conversion. damage is small pin holes due to corrosion. I'm Clifford glad to meet you all !
Here is how I would do it.
I am assuming you are making the repair from the outside.
Wire brush and degrease area thoroughly.
Prep area using 80 grit or coarser paper or grinder etc. Make sure you get down to good clean metal.
Clean area again finishing with acetone or other good cleaner that leaves no residue (not a water based cleaner).
Lay on epoxy resin and cloth, 1 or 2 layers would be plenty. For pinholes you could just use a thickener in the resin or chopped strands if you didn't have any cloth. (My preference is epoxy resin not polyester. Polyester will not stick to AL. as well as epoxy.)I have also seen products like 'marine tex' used for repair in similar applications (small holes only!). Prep remains the same. Whatever product you use make sure you put it on soon after the prep work to limit time AL. has to oxidize.
Keep in mind if you have many pinholes in the same area (usually a corner where the water in fuel sits) then that whole area is probably thin and suspect, so might benefit from a layer or two of FG.