To undercoat or not to undercoat.... [Archive]

brougham_geezer

11-02-09, 05:50 PM

In my eyes, there's no debate here. Undercoat the crap out of it. Make sure the underside is just dripping with the goop, and I'm talking every square inch. There is no downside except having a smokey/smelly car for a few days as the grease burns off the hot exhaust components. There is no better way to protect your car from elements, but even if you're not driving it in the winter, it can protect your frame, floor etc. from oxidizing and getting that "orange" "paintless" look. Undercoating makes for a clean looking car underneath, especially if done since new.

Up here, the ONLY old cars that are still presentable are ones that have been totally restored, OR sprayed underneath at least a few times over the years. Ziebart, Rustcheck and Krown seem to be the top big-name sprayers here, although many people go and get their cars sprayed in the "Cheaper" way with used diesel motor oil in some country garage. Many people I know swear by it, but it smells worse and seems to drip really bad... although old oil is what people used started using for the first undercoatings ever. It's also really thin and makes more of a black, greasy mess.

Now Canadian Tire has their own "Corrosion Free" treatment, and the stuff they used is a pretty advanced formula. Non-drip, tacky and totally moisture resistant. Since my dad / younger brother both work there, that's where we end up going. However, we don't trust anyone but my brother to be the person spraying, because we've had people half-ass it, and miss giant sections of hard to reach surfaces under the car.

We do under the under the hood, fenders, inside the bumpers, floors, above the gastank, doors, door bottoms, inside the rockers. etc. etc. Everything!

Yes it's a real mess, but you know it should be done when every car that we've bought/seen is can be put in two categories:

Non-undercoated = Ripe with rust and super scale-y.

or

Greased/Undercoated = Smooth looking, with solid metal underneath.

If you plan on storing the car, getting it sprayed once every few years is a good idea, but don't be too concerned about getting it done every year.

If you are driving it lots or in the winter, the undercoat seems to dry up. As a result, in the early summer you should chip off the dry stuff and then spray it again in the late summer. If you don't the new undercoat only sticks to the old flaky stuff, and falls off during the winter, and the salt rusts underneath thanks to a lack of coverage/good contact.

Some of you will think I'm an idiot and that the stuff is nothing but a mess... but man, my family has found it to be an amazing thing over the years, and incredibly helpful in preserving vehicles. We're massive supporters of this messy business.

My grandmother's 1985 Parisienne had one of its rear window full of Rust Check stickers (from 1986 until 2001 when we started going with Canadian tire), and that car was driven every winter. It is tough to find any rust underneath that thing... the massive amount of undercoat is the only thing setting it apart from its cancer-rotted sisters that have long since been doomed die in local junkyards... but our mechanic hated working on it.

Some mechanics, including ours hate that we undercoat because of the absolute sh*t show it can be to work on a heavily undercoated car. It's the messiest thing known to man, but at least you can expect to free every bolt and nut with ease! :yup:

If you don't want to deal with a big mess, just get a quick "under-car" spray at Canadian Tire, instead of the entire vehicle. You'll be putting some protection on the most vunerable spots (floor/trunkpans, inside bumpers, fenders, lips, gastank, rockers and the frame), and the rest should really be fine for just sitting around. Plus, it'd be much easier to wash up afterward.