You need to remove all of the rust prior to repainting the surface.
Roof frame rv rusted.
For severe rust which covers a large percentage of the frame or has begun to cause pitting or scaling on the metal a body shop like central body co inc is your best repair option.
You can flush water through the frame then follow up with compressed air to help the inside dry.
If you don t remove t.
Once this is complete the entire frame is painted with a rust resistant primer.
A light coating is not a problem but if the rust is thick it will eat right through the metal.
Keystone must put the thinnest coat of paint possible on frame.
It s important for consumers to know the underside of an rv might not be entirely corrosion resistant.
After years of driving the tubing can become filled with rust dirt and gravel allowing for moisture to soak and eventually rotting out the frame.
An rv specialist can blast it off repair any damage and then paint the undercarriage with a protective coating but having him do this job will be extremely expensive.
When a surface is rusted it continues to trap water will flake and then continue to rust.
The key to repairing surface rust on your rv is in the preparation.
When i got it home crawled under unit to check things out rusted frame rusted stabilizer jacks rusted gas line fasteners.