Think about how easy it is to crumble a flake of rust between your fingers, and then imagine that stuff trying to protect you and your loved ones during a car crash. A stray piece of gravel or a minor fender bender is all it takes to chip a car ’s paint, and any iron in the body panels will start to rust as soon as air and water reach the metal beneath it.
That means rust spots can be fairly common on used vehicles, particularly if they’ve been driven in a northern U.S. state that uses chemicals and salt to device winter roads. But if the rusting process goes on too long, it can eat right through the metal, causing holes and allowing body panels to fall to pieces.
This is where problems go from cosmetic to dangerous, because modern cars and SUVs rely on these body panels for their structural integrity. The most serious problems occur when rust gets beneath the car ’s surface and within its underlying components.
Rust -free body panels boost a vehicle’s structural integrity, but the parts doing the heavy lifting lie under the car ’s skin. Unfortunately, this area of a vehicle is often susceptible to rust -causing chemicals and water, which can accumulate there when a car drives down wet or icy roads.
Rust only needs a tiny crack in a car ’s structure (or truck frame) to do its work. Most customers should avoid used vehicles that show strong signs of structural rust.
CARFAX also recommends getting an expert inspection that includes putting the vehicle up on a lift, to give your mechanic a better view of under body components. You can apply touch-up paint to stone chips, small scratches, and other minor nicks and dings, but truly repairing rust can take several steps, a variety of tools and materials, and quite a bit of skill.
Depending on the size and severity of the rust, blending the repaired area with the surrounding paint may require wet sanding or buffing the surface. Dirt can retain and trap moisture, and road salt, bird droppings, and other corrosive materials will eat away at paint if they’re left unattended on metal surfaces for long periods.
Waxing it on a regular basis (twice or more each year) will add a protective surface to the paint and clear coat. Wash and wax more frequently if you live near an ocean or in an area where highway crews spread salt on the roads to melt snow and ice during the winter.
Also, frequently check the fender liners and other areas under the hood, along the sides of the engine bay, for any standing water. Check the trunk or cargo area to make sure water isn’t seeping past the seals.
Stone chips and other nicks and dings that are left unrepaired can develop into rust spots over time, so it pays to buy some matching touch-paint to cover those imperfections. While, there is no such thing as rust -proofing,” there ARE ways to slow down Mother Nature, hopefully until our loan payments are complete.
Automobile parts affected by rust can be very expensive to replace and rack up repair bills. Fortunately for your car, there are ways we can extend the life of those pricey parts.
This is most commonly found near the door frame, where the hood meets the fenders, and around the trunk. Parking your car on dirt, grass, snow, and poorly-drained areas is just an invitation for rust to form on your vehicle.
If you travel frequently on gravel or dirt roads, the mud and gunk that will collect underneath your vehicle will act as a moisture trap, speeding up the rate in which your car will rust. Keeping your fuel tank full during the wet season can help prevent condensation from rusting your parts.
If you drive a larger vehicle, dust and dirt from the road can gather on top of the fuel tank and lead to rusting. While having this fixed can be a bit pricey, a good DIY method is to spray some compressed air on the tank to dislodge the debris.
But haven't seen that in a long time, we don't have that issue as for the floorboards rusting through, usually the rest of the car will fall apart before the floor does since they make the floor out of a non rust type metal If you are trying to get your insurance company to pay for it, no, it will not happen...insurance companies total a vehicle when collision repair costs exceed a percentage of the value of the vehicle.
It sounds like you failed to perform required maintenance and destroyed your car by yourself. However, if you deal with rust early, you can stop it from spreading and squeeze a few extra years out of your vehicle.
Rust repair isn’t hard, but it is time-consuming (mostly waiting for primer and paint to dry between steps). Plan to spend about $100 on supplies like sandpaper, primer, masking tape and poly sheeting, a tack rag, polishing compound and touch-up paint and clear coat.
Buy automotive touch-up paint in pints and quarts to use in a spray gun, in aerosol cans, or in roller ball applicators. Pro-tip: Even if you know how to use a spray gun, mixing automotive paint with a reducer to match the temperature and humidity conditions can be mighty tricky.
Instead, buy aerosol cans for larger repairs and roller ball applicators to fix scratches. Buy 40-, 600- and 1,000-grit sandpaper, a sanding block, grease and wax remover, poly sheeting, painter's tape, a tack rag and a microfiber cloth.
Tape the leading edge of poly sheeting a few feet away from the repair so you'll have room to blend the touch-up paint into the good areas. If the rust has created pits in the metal, you can fill them now with body filler or wait until the epoxy primer dries and apply multiple coats of filler primer.
Wipe the area with a lint-free cloth to remove any remaining dust or lint. Spray the filler primer in heavier coats to cover the entire repair area.
Move the can away from the surface slightly and blend it into the surrounding painted area. Pro-tip: Self-etching epoxy primer provides a strong bond to bare metal, so use it as your first coat.
Wait a full hour for the epoxy to dry to the touch (longer if it's humid outside). Switch to wet 1,000-grit sandpaper to final-sand the entire repair, including the blended areas.
Start at the bottom of the repair and apply the color coat in left-to-right rows, overlapping each pass by about one-third. Pro-tip: Don't sand the base coat (especially metallic colors) unless you've created sags.
Gradually work the clear coat into the surrounding painted areas to achieve a smooth blend line. Note: This is the hardest part because all clear coats run easily and that will ruin the look of your paint job.
If you create a run in the clear coat, you'll have to let it dry for at least 48 hours before attempting to fix it with fine-grit sandpaper and polishing compound. So practice spraying on a scrap piece of cardboard to get a feel for the nozzle and the speed of application.
Robert Robert2111 gold badge11 silver badge33 bronze badges By the time the inspection was completed (and failed), I had a hole in my muffler system along with about $2,500 worth of rust related repairs for a $1000 vehicle.
However, to check you're going to have to do the squeeze test between fingers and thumb on the thicker structural sections, then if you still can 't determine how severe or not the rust is. It's time to get an old screwdriver out and tap (with the handle part) on the rustiest bits. If the material is corroded right through holes will likely appear, this is not good especially in the structural sections, if this is the case then you may like to walk away from this one as welding will be required.
If however it is just surface rust then a scrap off and clean up followed by an application of under body protection will suffice and your good to go. The seller should have no issues at all with you taping on the structural parts of the body to check its integrity.
In some parts of the world where lots of salt is used in the winter, this is not unusual rust. If you want to keep it longer term, I'd treat the rusty areas on the under body with a wire wheel brush on an angle grinder, rust converter and fresh undercoating after a thorough clean.