Look..no burnt paint!


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Look..no burnt paint!
Submitted by Jack Giannosa
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A discouraging aspect of a freshly detailed engine is burnt, dis-colored or peeling paint. This is a common occurrence on many Pontiac engines at the heat cross-over on the intake manifold and the exhaust ports on the heads. I've been asked about these areas on my engine last summer, of which I've had good luck with no paint burning in either area. In addition to the "high heat areas" the rest of the engine has a good finish too. Maybe it is just luck, but here's how I did it and so far it's held up well.
Since my GTO is a 1965 the engine color is light Blue or Robins-Egg Blue. I purchased a pint from Scott Tiemann and Scott wrote the ratio's of reducer/hardener-to-paint on the can.
Since I went through an entire engine tear-down and re-build the block, heads and intake manifold were hot tanked /acid dipped and all the other components were media blasted. After the engine was assembled I thoroughly wiped it down with TCI products "Wax and Grease Remover". Then an epoxy primer sealer was applied and within an hour two coats of the Pontiac Engine Blue were sprayed on. The intake manifold was off the engine in order to be able to paint the underside of it and get a good covering on the valley pan as well. The crank pulley was off too. The paint is Acrylic enamel and requires reducing and a hardener.
For the area of the cross-over on the intake there's a couple of ways to prevent the "burnt" condition. Intake gaskets with the "cross-over" section un-punched, (covered) are available. Warrior Racing Products in Westland, MI (734) 458-8560, stocks them, they're like $20 a pair. When I did my engine I bought the Felpro complete engine gasket kit so instead of the blocked heat cross-over gaskets I used the stock gasket and a piece of .006" thick stainless steel shim stock and covered the cross over port openings. Mark Orlowski and his brother Ken, who supplied the shim stock, suggested 

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this method to me. The little plates measure approximately 1 1/4" x 2 1/8" and are working well, there's no leaks and the Blue paint is not dis-colored or burnt at all…and that's with approximately 2700 miles on the engine so far. To assure a good seal I put a thin bead of High Temp Silicon sealant on both sides of the plate prior to torqueing the manifold down.
Gerry W. from our club mentioned that a small, (3/8" dia.) hole put in the center of the closed area that covers the ports will provide enough cross-over heat to allow the choke to work somewhat. I learned of this after the fact. During the hot summer months it's no problem, but in cooler weather mine runs a little rich cause the choke never opens all the way, and resetting the choke dial gets to be a pain. Electric chokes are available for the center carb by the way. NAPA has them for $52.
Another GTO owner I spoke to said if you fill the intake manifold and cylinder heads in the crossover area with aluminum, enough heat would be absorbed or "sunk away" and prevent the paint from burning. He did this on his engine and it worked well too.
The other area of concern is the exhaust manifolds if you decide to paint them, which I did, and the all too common Pontiac- exhaust-port-burnt paint syndrome. 
For the exhaust manifolds and ports I used a high temperature paint purchased from Year One. It's made by Bill Hirsch Automotive, item number: EMPT-14, High Temperature, 1800° Paint. The label is printed with "Exhaust & Manifold Paint" Color; Cast Iron. Eastwood has a similar product in 3 colors, with a temperature rating up to 1200°. I chose the Year One stuff because it had a higher temp rating and I liked the cast iron color. I'm sure the Eastwood product is good, but again the Hirsch product has a higher temp rating and I didn't want to do this more than once, (yeah right..)
The prep was the most important aspect of getting good results. Although they were new, I sand blasted the manifolds just prior to painting. I chose to spray it on and to make spraying easier I hung the manifolds on a piece of 2x4 with spikes through the mounting holes. Soon after sand blasting I hung the manifolds and sprayed them with TCI Products "Wax and Grease Remover" solvent using a Preval sprayer to sort of pre-clean just before painting. Then dried with the air hose and applied the paint in two thin coats waiting the time prescribed on the can between coats.
Since this was a small painting job I opted not to use a spray gun and used a Preval sprayer instead. It's a 2 oz. cartridge that screws onto an 8 oz. glass bottle. You can get them at NAPA or automotive paint suppliers. The Hirsch paint was thin enough right out of the pint can for the Preval sprayer, also by spraying the finish comes out more even.
I recommend getting some latex or disposable gloves though. They'll prevent any oils from your hands contaminating your part and also protect your hands from the paint..it's hard to remove. Also it stinks, so apply in a well ventilated area. NOT IN YOUR BASEMENT!
Give the paint several days to dry and your good to go. There will be some odor while the paint cures when you fire up the engine the first few times. When I was breaking in my cam and running the engine at 2500rpm for 20 minutes, the heat didn't hurt the paint at all. It's still looks good and there's and no signs of burning or dis-coloration...even after 2700 miles.
To do the exhaust ports on the heads required a little more work. Since the Pontiac Engine Blue was to be painted on the assembled engine I had to cover the exhaust ports with masking tape to prevent any blue enamel from getting on the area where the high temp paint was going to be. 
Before masking the exhaust ports however make sure there is no oil or oily film around and under the exposed head bolts located at the center, and end exhaust ports. I used the Wax and Grease Remover solvent and brushed some around the bolt heads, wiped with a clean rag several times and blew it off with an air hose to make sure it was oil free and dry. 
Using a good quality masking tape I masked off the area, carefully cutting and trimming with a xacto knife prior to spraying the engine Blue color. Note: After an hour or two remove the masking tape while the engine paint is still soft, this prevents the tape from pulling or peeling the paint and makes for a softer edge.
The next day I applied the high temp paint to the exhaust ports using a good quality 1/2" wide artists' paintbrush. I applied even coats, not going to heavy and worked my way down the area being sure not to re-brush painted areas. This paint starts to set-up rather quickly and if you keep going over it your liable to "pull" some of the paint and it'll tend to "ball up" and look crummy. Go easy with the brush to avoid "flinging" paint onto your freshly painted engine.
I suppose I could have sprayed the exhaust ports first with the high temp paint and then masked them off to apply the engine paint but I was leery of applying masking tape to the freshly painted ports prior to heat curing the high temp paint. Or…I could have sprayed the ports after painting the engine but it wasn't worth all the time and effort it would require to "mask" the entire engine with it's fresh coat of blue.
So..that's how I painted my engine and exhaust manifolds/exhaust ports. It may seem like a lot of detail work but I'm very happy with results so far and feel it was well worth the effort.

There is a much easier way however.... aluminum heads and Ceramic coated manifolds or headers…good luck.

Jack


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