DIY Undercoating

Welded structural joints that rust when you look at them, bolts that start rusting from the get go, here we go again.

Get under there early, see where the rust is starting, get it protected. Boiled linseed oil and a few brushes is working for me.

 

Very informative video. But now seeing the setup needed to hoist the car and what has to be done to get all the panels off, I don't think this is a typical DIY job for an ordinally car owner. And now I can see why the professional undercoating place did not even want to touch the car.

The video mentioned the stuff he used (from Canada) is a petroleum-based. It does look a lot like lanolin-based (non-petroleum) Fluid-Film. I wonder if he has to reapply this stuff every year like Fluid Film??? If so, it is more of the reason to believe that this is not a very cheap or easy DIY project.

 

He's got the car similar to an oil change pit, wheels off. Having the wheels off you could do a better job I think.

And yeah, I prefer a more surgical approach, with brushes. Maybe spray in corner that are unreachable.

It's almost good to let the rust get started, so you see the trouble spots. Then coat them well, seal out the oxygen.

Good underside pics btw: the proscribed front jacking point is soooo far back, I wonder if that front beam could take the weight?

 

anybody ever have their prius rust out?

 

It's important to rustproof the bolts, nuts and seams, as well as the brake line fittings and bleed valves. The cavities containing the "captive nuts" are also very important, as described in many post on how control arm bolts are "frozen" in place and nearly impossible to remove.

While "natural" or biological rustproofing works, I prefer petroleum based rustproofing, since it has the added benefit of repelling vermin like rats, mice, squirrels and chipmunks.

Rubberized undercoating is not rustproofing, as it traps moisture. It should be used only when applied as a mechanical barrier over rustproofing.