Hi fellow Lexuns
Recently whilst doing a underside inspection of my 1990 LS400 I discovered that the sill forward of the rear wheel had corroded from the inside,after further investigation it became clear as to why this had occured .
The underseal had been penetrated on the mudguard and this was not apparent as it is a rubberised formula that stays in place although the metal behind it as become exposed to road spray.Water had got in corroded the mudguard and seeped onto the insde face of the sill.I repaired that hole with epoxy and webbing as the metal is extremely thin at that point and would not have welded
We cut out 6 inches of sill welded in place (with an expert mig welder) a new peice, before we put the new panel in I cleaned out all the detrius and Painted all exposed metal I could reach with a top class zinc oxide paint.
After this operation I then pumped in through the rubber bungs on the sill and the chassis a full tin of waxoyl Put the waxoyl in a container in a pan of hot water before pumping as this makes its viscosity akin to oil and it spreads a lot better. The car stinks for a few weeks but at least you are corrosion free.
The idea is that in future I will do this on delivery of a new car