going to get some rust stuff to stop it eatting away at the metal and cover it with Hammer Right
This may slow it down a little, but I fear you may be just delaying the inevitable
if my deductions are correct.
I've examined the old plate and pipe. The pipe appears to be mild steel and the
the plate has the feel of alloy about it.
If I'm correct, what we have here is dis-similar metal corrosion. The 2 materials
will have a different electrical potential. If they contact each other, a small current
will pass, similar to a dry battery cell, which will result in galvanic corrosion.
The galvanic corrosion will break the paint seal on the outside of the pipe which
will than leave it susceptible to normal atmospheric corrosion. So in effect, the pipe
will be attacked from the inside and the outside. This would result in exfoliation
of the metal, (where its splits into layers), which is exactly what happened to my
pressure pipe.
Whether, assuming I'm correct, this is a design fault, or a quality control fault
at the sub-contractors that GM farmed the work out to, is unknown.
The designer would (should) have put an adequate seperation/sealant between
the 2 metals in the design specs. So that would leave the fault with the sub-contractor.
Whether this would be the quality inspector or the worker who made it, again we
don't know.
Anyway, upshot is, if your pipes are corroded then it is a case of when they
fail, not if.