I’m sure we’re all familiar with the rust that forms in the engine bay below the strut mounting. It is one of the most common areas to go through.
On my car this appears to be the worst area I’ve found. The rest of my floor seems to be solid, and my front subframe is sound, but I’ve got a hole the size of a tennis ball on the drivers side inner wing in the engine bay, and a much smaller one forming on the passenger side.
This is a double skinned section. The question is, how is the water getting in there? I don’t see any openings from inside the wheel arch that it could allow ingress, and the engine bay side stays dry.
Has anyone worked this out? I have found a few mentions online of rust in this place, but no information on how to treat it and stop it returning.
That looks like the type of repair I had in mind, but my concern is that by just patching over the hole, the rust will come back, or attack the other side of the panel, so long as water is still able to get in there. It doesn’t seem to have much of a place to drain from either, so I can imagine it pooling in there for a prolonged period until it finally escapes by eating all the metal.
Ideally I’d like to seal up the seams in the double skin where it’s possible to do so, and pack the space out with grease or something. I just can’t find anywhere obvious where the water is able to get between the two skins.
Nice link, thank you!. I haven’t encountered rust there on my 3 XJ-S’s. just the boot lid trailing edge just above the bumper, the flying buttresses from the Stainless Steel trim giving the buttress a poke every now and again.
Though this would be a bit tough to ID with all the V12 stuff in the way. Now I’m going to check it out.
hey guys its the type of metal used , it attracts humidity from the AIR!
ever notice Japan cars built after 1990/91, have little to no rust!
thats when eletro coating bare shells dipped in huge vats and electro shocked(or something),
got into all the small crevices /joints and came out and baked!
USA made it manditory for all vehicles to be done that way!
not much rust nowadays(unless accident and bare metals added to structure).
Utter nonsense. Compared to the numbers sold new in the UK, were here are virtually no 80s & 90s Japanese cars left on the roads & the reason is not mechanical failure (those engines were like sewing machines), the reason is corrosion.
ANDY read cars made after 1990/_ onward, especially new models , i have a 2002 Mitsu. many times driven on the pure salt BONNEVILLE , absolutly not sign of any rust, hose areas off and shiny paint any place on it!
WHY do you think US government made it manditory for the electro coating in early 90s!
course if you break away accident joints things can change!
i,m just sayin like it is!!!?
i wish i had apic of the SALT packin up look like snow packup under the cars and wells!
You guys are not in Michigan, they use brine AND salt on the roads 4 months out of the year. Not unusual to see 4 or 5 year old domestic or Japanese cars with rust holes. The is a 2015 Mazda down the street with rotted out quarters.
I had incorrectly assumed the entire wing was a double skinned section when it isn’t, it’s just a single skin with that reinforcing plate. I can see where salt as stuff has got down in the back. Grr.
Still, I can also see a way to deal with this rust more permenently. Once the metal has been replaced, I can force some grease down between the two panels, then seal them up with silicone, and maybe drill a small drain hole on the engine bay side just in case anything more does manage to get in. Maybe also something like a plastic wheel arch liner could go some way to preventing crap from getting flicked in there.
I’ve finished inspecting the rest of the car’s frame for rust. The rear end is spotless. All the underseal is original or very old, and there’s no sign of any weakness or flaking. Rear subframe could use a paint but it’s so hard to get anything in there. Radius arm area is solid, Sills are all clean and original, jacking points are strong. This inner wing area is the only serious rot on the car. It’s a good, solid chassis, so the fact it’s gone so badly in a single place suggests that it is a major rust trap!
After working in a body shop years ago rust repair was the most hated job. Salt,snow slush etc would do you car in, no matter what "rust proofing"was used. The worst has to be “trying” to welding in a patch that the owner used oil as “rust proofing”. Lucky I didn’t burn the shop down.
I’ll swap ya '92s, then! btw, do you happen to have a copy of the '91-'92 driver’s handbook? I am STILL trying to find a copy, but all I ever have been able to find is that same vendor on Ebay who insists on $500+ for his (full owner’s manual set, though).
btw, do you happen to have a copy of the '91-'92 driver’s handbook? I am STILL trying to find a copy, but all I ever have been able to find is that same vendor on Ebay who insists on $500+ for his (full owner’s manual set, though). 
