What is everyones preference for engine paint.

Urathane?

Also; What is the primary differences between accelarated urathane like IMRON and non-acclerated like AWLGRIP?

You need too find a paint with Ceramic in it, that will hold up to the heat.

Paints can be grouped into classes or types, aliphatic urethanes, alkyd modified urthanes, aeromatic urethanes, polyamide epoxy, novolac epoxy etc etc... ....Each has it place for chemical resistance heat resistance UV resistance etc... When purchasing paint look at the very small lable near the bottom of the can or on the MSDS sheet - this will list contents - this will often tell you what generic type of paint you are dealing with -

Engine paints - stay away from paint that are Hi-temp these perform poorly on any surface other than a surface that is over 750 degrees - Paints in a spray can are most often Alkyd based and do a nice job for touch up but are not very chemically resistant and have a maximum continous temp of 180 degrees F. Epoxy (2-part type) will work well if you can find the correct color - epoxiess are very stable to 250 degrees ( rememeber your engine has a thermostat and rarely gets more than 200) and since engines are not exposed to sunlight ,will work well ( epoxies chaulk when exposed to sunlight) Epoxies as a general class are chemically resistant ( oil gas spills etc...) and will work well, but are difficult to tint and are often a semi-gloss. Urethanes - many paints are called urethane or poyurethane - For long term color and gloss retention, very good general chemical resistance ( except to continous imersion in water/ hull in the water) you need a catalized urethane ( these will most often be aliphatic urethane) same stuff your car is painted with - As long as you buy into a type of paint rather than a manufactuer you will be good - ok ok ok - a little long - Purchase Imron or Alwgrip International Tnemec or any other such brand and your engine will look great - ok next problem - Your engine is currently painted - A tuff product like aliphatic urethane also has strong solvents within and they will most often cause a weaker paint like an alkyd to fail, if you paint over and existing paint - Use MEK on a rag and rub your existing paint - if the paint does not soften paint the engine with anything - I if the paint softens you can only top coat this with an alkyd type paint

Good luck

My engine guy uses acrylic enamel and the they have always looked great and easy to keep clean, very durable.

jamess4;

Great reply, thanks!

Imron vs Awlgrip on the bilge surfaces, other than catalyst, what pros and cons exist there?

Jamess4, thanks for the info. good stuff.

I used awlgrip in my bilge because I was able to brush it. Rock solid so far even after a couple engine explosions.

Great forum
What advice for primer on unpainted engine parts?
What about exhaust?

The Blue paint is faster .....

Sorry guys I don't know much about the alwgrip line but will look into it so that I may reply to these post with materials that are easily accessable to boaters -

Keep in mind simply adding a catalyst to any old paint does not make it better - ( the exception adding beer to my X wife made her better) -

As a rule of thumb for paints that will be used in non imersion enviornments - Two part Epoxy will do everything you need but will fail quickly in sunlight - Two part polyurethanes will do everyting you need including exterior surfaces ,are also more expensive but should not be used for continous imersion - use it in you bildge just do not let water stand more than 30 days or you "may" see blisters -

Most single component paints that are easy to use and low cost will have the draw back of being low performance , no hold up to oil & grease/ sunlight/ heat/ chemicals -

One of these post said said "acrylic enamel" - this is really a type of polyurethane, slightly lower cost but will also perform well on and engine - tuff thing is that these words like acrylic enamel really do not explian the material - "acylic" can be one of many plastics "enamel" by definition is " paint that dries to a hard glossy surface". Be careful with general definitions and descriptions, they may not accurately represent the product. I have a can of spray paint that is labled "epoxy" yet the ingrediats on the side of the can only show the contents are alkyds.

Try Awlgrip.com - they have a pretty good site that describes primers and paints for each different type of surface - Mixing and matching different brands and types can lead to trouble - boating is not supposed to be cheap - prep it- and spend a lot on paint and you will have good finish results -