Old Man Minimalist

Working on my XJ, initially I was going to do a full factory restore, but I'm pretty sure I will stray more into the restomod (if there is such a thing for xj's) territory. I'll do stuff like update the battery cables, headlight wiring, kil-mat the interior, possibly add a trans cooler. etc. This will be my daily driver/retirement vehicle. Which means it will see very little off-roading but will be driven in rain and occasional snow.

It currently has no rust and I want to keep it that way. I am cleaning and painting anything that I restore before putting it back together whether it be a chassis component, oil pan, bracket, back side of bumper, etc.

For the underside I vacillate between spraying some body color paint like original or spraying it black.

In all my other vehicles, I painted everything black and then just got under it once a year, cleaned it up real good and resprayed parts of it.

Interested in the forums perspectives. Thanks.

dmoe69

I think it is difficult if not impossible to keep the body color clean under there. On my buff tan XJ my eye is always being enticed down to look at the grungy tan behind the driver's front wheel. The transmission brace also is the prominent fixture below the vehicle and mine is black. I think that was a factory decision. This is my 100th post, I think I get to ditch the "Junior" status!

Old Man Minimalist

Funny, it is the area behind the front wheel that is in question for me. It is the most noticeable. I am leaning towards black.

Congrats on hitting the 100 mark! You are now a "member"!

robsjeep

Is not the textured undercoating from factory black on all the xjs? Under the undercoating is grey paint.

The color of the paint should not factor into easy of cleaning. Perhaps texture does, but not color.

I say go with factory color as you have mentioned restoring.

original color is a nice thing, specially as our vehicles become classics

I have regret from my youthful days of color changes on cars I own. Keep it stock color is best for me,

Rogue4x4

Black. Only show vehicles should be painted underneath, haha

Seriously, though, you can touch up black easily, and any spray on undercoating is usually darker in color, you can POR15 or fluid film once a year (if necessary) after a thorough power wash. Why go to all the trouble if it's just going to get dirt, mud, grime, and debris?

K.I.S.S. theory applies here, lol

robsjeep

Remember if using a rattle can... Rattle can paint is VERY thin, it has lots of solvent added to make it thin enough to spray with the limited pressure and volume of the compressed gas inside the can. This means that although coverage maybe smooth and uniform from a distance, the paint film will be extremely thin. Rought edges, outside corners, or tiny peaks in the metal may poke thru the thin paint film. This leaves pathways for rust. With rattle cans, for a finish on the underbody which must be tough, you will NEED many many coats. Of course you need drying in between coats, you will find you may need heatlamps between coats to assure full cure after 3 or more coats. Note the instructions, some types require a very short recoat window, then you MUST wait a weak before further coats. Not all brands have same limitiations, read the can as there can be huge differences, and if you get it wrong, yes the entire paint job my wrinkle and peel. Id do 2 or 3 coats of primer, cure inbetween coats, followed by three of top coat. Wear a N95 for this, and do it outside, protect property and driveway from a cloud of paint, Because rattlecan paint is so solvent laden, it must be applied in many many coats to get a thick enough layer

If you plan on a textured surface, or dont mind brush marks then rustoleum red rust brush on primer, three coats. then once full cured, top coat with 1. Rustoleum rattle can (it is compatible), or.... 2. Brush on top color, or....3, textured undercoat.

The brush on rustoleum is rugged stuff, I used it. the key to minimizing brush marks are..

A...
Quality Brush of Correct Type. Some brushes are for oil based paint like Rustoleum, other brushes are for latex or water based paints. Natural verses Synthetic bristles. In general natural bristles work best for oil based paints, synthetic bristles tend to leave marks, paint dosent wet them the same , but synthetic are better for water based paints. It should say on the label. Get the oil brush, avoid the all purpose and water based brushes. all purpose brushes are a compromise not the best.

B.
Thin the brush on paint a bit. Do,this in a small batch size disposable paper cup. Do not add thinner to the paint can entire contents. this way if you over add thinner in the smaller paper cup, you can recover by adding more unthinned paint. Usually no more than a few percent added thinner is needed, a little goes a LONG way, dont over do it! . ONLY use the thinner listed on the lable. generic laint thinner typically used for cleaning may not be compatible. Make sure you are using the correct thinner. Thinning paint even just by a little bit can make a huge difference in finish qualty with a brush, experiment with what amount works best

C
Stir the paint, scrape the sides and bottom, a lot of pigment settles in a thick layer there, specially when sitting for weeks or months. stir until your tired, most cans need a couple minutes of vigourous stirring AND scrapping the sides and bottom to make the mix uniform. then pour a small amount into the cup, then add the thinner in the cup, stir that now Also...stir while painting. (use a stir stick, NOT the brush***) the pigments settle out fast, so stir!

D
*** Do not dip the brush more than half way up the length of bristles if you over load the brush, then gobs of paint will unevenly flow out onto your substrate.

Old Man Minimalist

I went black. Fired up my $8 HF paint gun, mixed some black up and hit it. It worked out well. Pic was more for my driveline work, but you can see the black.