Those of you who have painted the engine, what prep work needs to be done? Do you have to shoot it with primer like you would with the tins, or just shoot the color and clear coat and be done with it? I know I will have to buff off the existing clear coat from the factory and all of that so the paint will stick. I am just wondering about primer.

To make this even more convoluted and confusing, I plan on only painting the side covers and head cover and that little piece of tin just behind the starter.

Let me know of any other prep work that will need to be done as well please. Greatly appreciate it.

Problem is, I don't think they make the color I want in actual "engine paint". I too am surprised nobody has chimed in.

Can't afford powder coating, if I could I would get the frame powder coated as well.

There is a store down here that will custom mix paint, I will have to check to see if they can do a high temp resistant paint. What I want to do is paint the side covers, the head cover and that little piece of tin behind the starter the same color as my tins.

I'm going with a candy blue with metal flake if I can get it for the tins, and just candy blue for the engine parts.

Gonna try to put some kind of graphic on the tins, just haven't decided what yet.

Yes, I have a gun and compressor and masks.

This isn't a cheap solution, but it is a lasting one.
As stated before preperation is critical. If it still has any oil at all the paint will flake off in time.
The surface being painted has to be scuffed. You will never get sand paper between the fins. Use a scotch brite pad. These come in different grits like sand paper. I normally use 3M green. Wrap a paint stick or popcycle stick to get between the fins. You don't need to get down to shinny metal. Just get it scuffed.
Use an air nozzle to blow as much of the dust off as possible. Then mask the area so you are just painting the parts you want. Then using the new type of tack rag (not sticky but has small loops to catch the dust) carefully wipe the area including between the fins. Dirt here will transfer to the top coat.

I would not use a full size gun to spray the jug. I like the Badger 250-2. It is available online. Try Tower Hobby ($14). You will have to modify the air hose to connect to a compressor. Cut the little hose fitting out of the Propel can adapter. Drill a hole in a pipe cap. Solder the tiny fitting into the pipe cap. Screw your hose fitting into the cap. I use about 20 to 30 psi on mine. The tip is adjustable. Experiment on something else first! When spraying in the fins go with a light coat so the air will take it deap into them without putting runs on the outside. You need a good coverage but you do not need to build thickness.

Use a self etching primer. Omni makes some that won't break the bank and works well. This is 2 part paint so you need the primer and catalist. (MP170 [grey, other colors are other numbers], and 175 catalist)
Epoxy primer does NOT get sanded. Thats why the part had to be clean before priming. It doesn't build much thickness. It must be topcoated within 5 days. Make sure the primer is dry (minimum 4 hr at room temp) before topcoating. You must wear an appropriate respirator.

I would not use high build primer on the motor. Adding paint thickness will cause it to run hot. The paint eliminates heat transfer. Painting the jug will cause the motor temp to increase. Adding more paint will only make the problem worse.

Next you have the option of single stage or 2 stage paint. It must be urethane. The others will not last. The Omni single stage uses the same hardner as the clear. House of Color makes some pretty stuff. PPG and Dupont are both high quality paint. If you chose the 2 stage you will need to buy some clear of the same brand as the color. The clear will come in 3 types. Fast which is for door jams, OEM repair which has a bit of orange peel in it. You do NOT want either of these. You want the stuff that goes on slick and can be sanded and buffed. (If you choose Omni - MC161 with MH167, 168, or 169 hardner) All of this stuff is 2 part paint. You will need some thinner of the same brand also.

If you want a true candy color this will require another coat of paint. 1st is the base coat, normally silver, 2nd is the candy color, you said blue, 3rd is the clear coat. This will be difficult to do! The jug is a hard part to apply paint evenly to. The blue candy color will be different shades if it is not evenly applied. That means at a minimum the inner part of the fins will be lighter than the outer part. You just can't get as much paint inside the fins.

If you are wanting metalic in some an not others that will not only add sparkle but will change the color of the paint. Pearl will do the same thing. It is very easy to come up with some really ugly colors when adding a little extra to the paint. Some of these comginations will look good in one light and bad in another light. (night/day or sunny/cloudy) If you are going to use the same paint for the rest of the bike I suggest using the 2 stage system. The clear makes it so much easier to sand and buff. Unless you are in a quality paint booth you will get dirt in the paint. It is just a fact of painting. If you want it slick it needs color sanded and buffed. That is another complete story.
I have not painted a Savage cylinder. I have done several HD jugs. Depending on the color of those, there was a slight discoloration at the exhaust port after time. Black naturally didn't show this. The lighter the color the more it showed. I normally used silver.
I have been thinking about bobbing my Savage. I like the old school heavy metalflake. Again this is hard to apply evenly. The big flake needs a LOT of clear to cover. Then it is sanded heavily before buffing to make the top slick. To make this a super job the frame should be the same color. Making the frame slick is another whole issue too. In the end it comes down to how nice does it need to be to make you happy and what can you afford to do. I went lazy. The bike was black already, the frame is already black, so I repainted what I had to black. It helped that I already had black paint. I wimped out on bobbing it too, but I'm still dreaming of a bobber with orange flake on top of orange pearl on everything.

Oops. I guess I should read better.
The same basic principle goes for those parts too. I would still avoid high solid/build primers on those parts. Candy is still a pain in the rear. House of Color can be purchsed mail order. They make some of the best candy colors. True candy will always take 3 steps, base, candy, and clear. I am a big fan of the high pearl which all the brands can mix. That is just 2 steps since the pearl is with the color.
I painted my tank (again) yesterday. I got plenty of dust in it. I buffed it this afternoon. It still needs a bit more work to be slick enough.