If you don't strip the old paint off, the new paint adhesion is only as good as the old paint underneath.
Whenever I repaint the plenum an valve covers, I totally strip the metal. Aircraft Stripper is a favorite product. Almost anything you use will require multiple applications and a good scraper and wire brush to get everything. An easy way is to take it to an automotive repair shop and have it hot tanked.
After it's stripped, you can wash it with a solution of TSP, found at some grocery stores and most large hardware stores. This is a degreaser. Rinse and Rinse and Rinse after every step.
Finally, wash the surfaces of the pieces with pure white vinegar and rinse some more. Let it air dry. After the final rinse, prior to priming, do not touch the surfaces to be painted with your hands or anything that will leave a residue.
I use an aerosol can of Zinc Chromate Primer. This is the same primer used for painting aircraft because it adheres so well to aluminum. Let it bake in the sun or under a heat lamp. I like to give it as much exposure as I can in a 24 hour drying period.
I use High Temp Ford Engine Red in an aerosol can. Others have their choice, but to me, it appears to be the closest match to the original red. Not the faded red that we have now, but the original red. Again, let the pieces dry using the above method I described.
A window scraper of the type that uses a single edge razor blade can be used to remove the paint and primer from the flat surfaces. On the valve covers, place the blade across the surface of 2 ribs and holding it at about a 45 degree angle, push. This gives support to both ends of the blade to prevent cutting into the edges of the ribs. Same goes for the ribbing on the intake.
Using a power or hand pad sander , sand off the remaining primer and paint stain on the surfaces that will be polished. Using a fine grit to finish up for a more polished finish. Be sure to rinse well to remove all residue of your paint removing efforts.
Now, this is where you want to be alone. Mom, Dad, Brothers and Sisters should be gone for a couple of hours if you are living at home. Wife, kids, and Mother-In-Law if you're married. Preheat the oven to about 250 degrees. Place the items in the oven for about 20 minutes. This will set the paint and primer and slightly change the color of the paint.
[This message has been edited by fierofool (edited 03-08-2015).]
Both work just fine. Usually it's a matter of color preference. If you are trying to match the original red, the closest thing seems to be Chrysler Engine Red in a spray can, or the Ford red that Fierofool mentioned. It's hard to say because paint fades over time, and even the 'factory' color seems to have changed a bit now and then. What is odd, is that Chevrolet engine red and Chevrolet engine orange do not seem to be a good match, and those guys built the engine! The powder coat colors are more limited, but more durable..and more expensive.
[This message has been edited by Gall757 (edited 03-08-2015).]
Is there general agreement that painting is preferred over powder coating? Was the factory finish paint for powder coat?
Just getting ready to redo a set of valve covers and intakes and was going to start a new thread on it when I saw this one.
in the 80's it was more than likely painted on, then baked... powder coating is just painting without the emissions. If you use paint, and cure it by baking it, it is just as tuff as powder coated part.. If you read most paints , to get the tuffest finish, they instruct you to bake the painted item.. Many people have problems with engine paint and header paint because of this.. painting an engine then using the engine heat to cure it ,doesn't work as the painted part of the engine doesn't get hot enough. and you can't fire it up weeks after painting it and hope it'll cure,then.. powder coat colors are far from limited.. powder coating is easier for many people because most will get killed if the wife finds out you cured paint in your oven, and it tends to smell as it bakes. and why every garage should have a 50.00 yardsale stove..
Is there general agreement that painting is preferred over powder coating? Was the factory finish paint for powder coat?
Just getting ready to redo a set of valve covers and intakes and was going to start a new thread on it when I saw this one.
I prefer powder coating.. My color is called red Barron and like the others say about their color choice, this is a great match also. It doesn't have that orange red color that I've seen on some..
Prepping from the coaters is by sandblasting, cleaned with some kind of acetone, I would imagine, and then baked.. Cured Powered coating withstands 800 degrees seems to be really strong. It's Like taking multiple coats of paint and then baked.. Multiple, I mean 5 at least!... There's more thickness to powder coating. I think that's why , in a jeep world, bumpers, suspension, diffcovers, etc are all powder coated. For rock and abuse reasons....
[This message has been edited by unboundmo (edited 03-08-2015).]
in the 80's it was more than likely painted on, then baked... powder coating is just painting without the emissions. If you use paint, and cure it by baking it, it is just as tuff as powder coated part.. If you read most paints , to get the tuffest finish, they instruct you to bake the painted item.. Many people have problems with engine paint and header paint because of this.. painting an engine then using the engine heat to cure it ,doesn't work as the painted part of the engine doesn't get hot enough. and you can't fire it up weeks after painting it and hope it'll cure,then.. powder coat colors are far from limited.. powder coating is easier for many people because most will get killed if the wife finds out you cured paint in your oven, and it tends to smell as it bakes. and why every garage should have a 50.00 yardsale stove..
good luck..
Baking is the secret to longevity. I have one set of covers and plenum out there that's been on the car for about 7 years and 1 small engine bay fire. Still looks good without chipping or flaking. Baking also helps prevent oils and stains from soaking into the painted finish. You can even put a high temp clear coat over the whole thing before baking, too.
And the solution to the smell of baking in the kitchen oven....See my above instructions to be sure everyone is gone for several hours and if the smell lingers, resort to step 2. Play dumb and Lie, Lie, Lie, Lie!
in the 80's it was more than likely painted on, then baked...
good luck..
Powder coating was actually developed back in the 40's and there were a number of different methods of doing it. It came to be more popular in the US in the 50's using the electrostatic process but was pretty much limited to things requiring a heavy application. Snapper Mowers of McDonough, Ga. used it extensively on the bodies of their lawn mowers and other small power products and later Craftsman among other industries adopted the process.
It wasn't until sometime in the late 70's or early 80's that thin-film powders were developed that could effectively be applied to smaller or more intricate parts. It may be possible that the engine parts are powder coated.
What I usually do to engines on my own cars is strip it if necessary, then power wash it GOOD, wipe down with thinner and a red scotchbrite pad, wash again, spray on a light coat of zinc-chromate (yellow or green)...examine carefully for specs of primer that wont dry indicating stripper specks... and just normal automotive paint or spray can. THEN I go over it all with a Benz-o torch lightly to get it hot but not burned, to bake it dry. You have to MAKE SURE there are NO specks of stripper left before you put on paint. The paint on them will not dry and wash off the first time it gets wet.
Hey guys, just an idea. Instead of using the oven in the house could you use an outdoor BBQ grill ? I have mine hooked up to a natural gas line so I wouldn't have to worry about running out of propane. Just an idea. If this is a good idea, how far from the burner should the parts be placed ?
Hey there's a thought, why doesn't any one make a gas grill with a thermostatically controlled burner?
My grill has a gauge in the lid, the gas controls are adjustable like a stovetop, to control the size of the flame. And the sides of the lid have adjustable vents. So I think you could do it on a grill, you'd just have to pre-heat to get the settings where you want them to have the correct heat.. I could most likely fit 2 v8 valve covers in at once, in mine. Anything bigger would be a problem. I like the oven Idea, as it has racks .
I don't know about the BBQ idea.. The burners are somewhat exposed in mine where the oven is more indirect/radiant heat... I feel the open flame will discolor the part in places... PLUS, every time I drive the car I'd be like... Mmmm hungry? How 'bout BBQ?! -smelling the parts.
