rubberized undercoating on engine bay yay or nay?
 

i want to paint my engine pay with rubberized undercoating next time i pull all my manifolds and shit, any thoughts?
i think it would help prevent potential rust and quite honestly look cooler than rattle can black. but would heat be an issie? i would think it would hold heat in more but im not sure, plus i dont know how flammable that crap is.

Rubber would melt, but if you got it ceramicoated, and then painted flat black, it would probably have the same effect. You are talking about bed lining material right? If you are, it would definitely melt.

I think he's talking about POR-15.

POR-15POR-15POR-15POR-15POR-15POR-15POR-15POR-
15POR-15POR-15POR-15POR-15POR-15POR-15POR-15POR-
15POR-15POR-15POR-15POR-15POR-15POR-15POR-15POR-
15POR-15POR-15POR-15POR-15POR-15POR-15POR-15POR-
15POR-15POR-15POR-15POR-15POR-15POR-15POR-15POR-
15POR-15POR-15POR-15POR-15POR-15POR-15POR-
15POR-15POR-15POR-15POR-15POR-15

POR-15

is the best crap

you could use POR-15 and not rubber coat it. I would only say rubber coat it, if sound deadining were an issue. It adds alot of weight.

*didnt have a clue what POR 15 was* used the google and figured it out.
I would say give it a shot. The worst thing that happens is that it chips off, and you try something else.

do you guys think i ment on the engine? im talking about the body the engine bay its seld. the engine will not be painted

POR-15 prevents rust and looks like paint. You have to get rid of any rust showing though. I think the rubberized engine bay would look horrible. But that just my opinion.

I dont think that rubberized undercoating will melt but it definetly will not look good on your engine bay. Have you sprayed that stuff before, its like spraying thick glue.

The makers of por15 have a high temp. black paint. if thats what you want, check their website.

[QUOTE=Rotary Noob;6266947]Rubber would melt, but if you got it ceramicoated, and then painted flat black, it would probably have the same effect. You are talking about bed lining material right? If you are, it would definitely melt.[/QUOTE
Noob, you have no idea what you're talking about. I think if he wanted the effect of paint he probably would've just painted the thing there's a reason he wants it thicker. I have rubberized undercoating all up in the engine bay of my turbo 1988 Mazda RX-7 and it never even thought about melting. I've even had my entire turbo charger and exhaust all the way down to the end of the downpipe glowing bright ass red and it still never bubbled or anything. The stuff I used came out of a spray can. You can see a YouTube video of it right after I got it done in my build montage. You can find that here in the forums or you can just search Donald Fenton Rx7 on YouTube and I should come up. I left the tops of the wheel wells just went to the top of the trim piece on the firewall. I never have to worry about those two main frame rails rusting again. I'll resurrect this thread again in another 10 years. I'll update ya ;)

The undercoat would not melt but if your main goal is better aesthetics, it's not your best option.

Cleaning out and painting the bay is a big job- lots of nooks&crannies to get at- and well worth a bit of R&D first. I'd get a piece of scrap sheetmetal and spray it with your proposed product, then see how it holds up to the common chemicals it might get doused with. Like gas, brake fluid, PurplePower, etc.
A brush on bedliner would have a tougher finish.

POR-15 is the gold standard but requires the most demanding prep.

While I've never done it myself, I've seen rubberized coating used in the engine bay and it seems to hold up just fine. Either by itself or overcoated with another paint.

If you are going to use the POR-15 rust paint, it should ultimately be overcoated with something else anyway. Which if you want to last either needs to be done while the POR-15 is still tacky or you need to use the tie coat primer.

I bought a car that someone had "undercoated" and it was a total MESS.
That shit holds in road grime and whatever else it gets in contact with.

I swore I had 2 things to do..
1: get the stuff off.
2: find the asshole that did it and give him a good swift kick in the nuts!

Yay..white car.black tar...

The undercoating would hold onto oil like crazy and would not look that great, unless you go full 4x4 status and use Rhino Liner.

I'm in the process of scrapping off the undercoating on the underside of my car I have been considering doing either POR-15 in black on the underside, like Aaron Cake did, or spray the POR-15 undercoating that they have on their website. I may just get some generic chassis paint and spray it that way. The garage is freezing now, so motivation is lost.

While rubberized undercoating holds up fine... I had a car that had Rusty's under the hood and it was always sticky and gooey... Like touching old oily electrical tape on the engine harness, the kind that turns your hands all black and sticky.

I vote truck bed coating. I bed linered mine while the engine was out and under construction. Here's mine...

Attachment 617324
Attachment 617325

There are multiple types of undercoating remember. There is the style that stays gooey, almost tar like. Then there is the really rubbery stuff that is still rather soft. There is also the less rubbery stuff which is designed to be overcoated, and still has a little give. The varying results could be accounted for by the different interpretation of "undercoating".

POR-15 products are rather pricey and you have to use the namesake product right away because it goes bad even if the can isn't opened. Apparently following the entire ritual with all the ancillary products is important or it flakes off. You may find it best to just get a pint (with ancillary products) and just hit the rusty areas religiously following the multi-step procedure.

Greg's Garage on YouTube used U-Pol RaptorLiner to undercoat his VW Karman Ghia resto. It's a two-part epoxy bedliner and it's tintable so you can match the body color.

Personally I wouldn't use anything that stayed soft or gooshy.

surprised no one mentioned plasti dip, which i believe is similar to viton and rather chemical resistant aside from alcohol.

I have used Plasti-Dip for various applications since the '90s and in my opinion using it the engine bay environment is just asking it to peel as heat causes it to off-gas and pull away from the sheetmetal and oil gets under and edge.

If you put it on really thick (like as on pliers handles) it will resist this well or if you overlay it on something absorbent like cloth. Putting it on that thick would cost and weigh a lot.

I use that Blue Label Duplicolor truck bed liner for many cheap ass race car purposes. The only problem with this product in the engine bay would be it bubbles and eventually hardens with high heat.

I tried using it on my wheels and after racing it bubbled in the center from bearing and brake rotor heat conducted through the hub and now is crumbly there as well.

I tried using the Black label Duplicolor "Armor Coat" which is more rubberized to stealth out my IC end tanks and it quickly bubbled/peeled with heat.

Blue label Duplicolor truck bed liner would probably work fine under the hood if you don't have a turbo and/or don't race. Even if you do have a turbo and race you could put some heat foil around the turbo area or mask it and use header paint there instead.

You can top coat the Duplicolor to make it more fade/chemical resistant and it works very well. I have a friend that did that to his bumper and hood after several years of bare Duplicolor.

Plastidip does not like prolonged exposure to gasoline, but our gas has alcohol in it (thanks a lot, Big Corn) so maybe that's what softens it.

I used Rustoleum Truck Bed Liner on the undercarriage and bay of the Z and it's held up very well through endless mechanical work (two engine swaps) and a persistent (undiscovered) brake fluid leak.
In hindsight, we shoulda/coulda sprayed a coat of satin black over the liner, just for the aesthetic upgrade as the liner is a flat(ish) black.

No matter what you end up using, be prepared to spend forever chasing threads in all the capture nuts you'll clog with paint. There are a metric crapton of them.

makes you think, perhaps just respraying it properly with automotive urethane isn't such a bad idea... lol