Repainting Engines

Discussion in 'Diesel Engines' started by majorm, Jul 28, 2013.

  1. majorm
    Joined: Apr 2012
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    majorm Junior Member

    I need to refinish two engines that will be in a boat used in salt water. They are Cummins 4BT's and have some rust and peeling pant where it wasnt applied properly before. Have any of you found some products or procedures that seem to work well and what do you think about some of the more performance coatings for certain parts. By performance coatings im refering to things like Cerakotes Turbine coat and the exhaust coatings. http://www.cerakotehightemp.com/finishes/C-217Q/

    Prep wise I dont have good access to somewhere to abrasive blast so are there any other good alternatives that dont cost a fortune. I thought about a needle scaler but know that would take forever and dont know how well it would really work.

    Let me know what yall think and if you have any more info you need just ask.
     
  2. michael pierzga
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    michael pierzga Senior Member

    Degrease and paint. I prefer 2 part paint. Awlgrip white. It does not yellow with age.

    Takes a few coats. Work green on green. thin coats. apply with a paint brush.

    Degrease first with detergent and plenty of water...then degrease again with solvent. Trichloroethylene is a very powerful degreaser. Illegal in some places. Don't kill yourself.

    High temp components are not painted..they are insulated with packing.

    A needle gun can be used if you have a previous heavy paint build up, The old paint jumps right off.

    Paint remover is handy for some details.

    When using HARD 2 component paint do not allow the paint to enter lip seals...dont paint shafts or lip seals.
     
  3. PAR
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    PAR Yacht Designer/Builder

    Two part LPU on a diesel - really? The factories don't even do this. LPU's generally are not flexible enough for this application. A single part polyurethane works much better (and is what the factories use).

    The hardware store will carry several brands of high temperature polyurethane, in brush or spray cans. If the surface is clean, these work very will and have the flexibility to work, particularly on aluminum and sheet steel, as these parts will expand 2 to 3 times as much as the iron and heavy steel pieces. Besides, using $300+ per gallon paint on an engine just seems silly to me. Buy a couple of $8 spray cans of VHT engine paint and have fun.
     
  4. michael pierzga
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    michael pierzga Senior Member

    A marine engine runs cool. No need for high temp paint.

    The fast dry time of two part paint is very desirable.
     
  5. PAR
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    PAR Yacht Designer/Builder

    Again, $300+ per gallon LPU, not counting special reducers, wetting agents, etc., versus an $8 can of spray paint - really?
     
  6. michael pierzga
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    michael pierzga Senior Member

    Gee ...with a gallon of Awlgrip you can paint your engine. engine room and re coat your topsides !!!

    Id suggest a quart. International makes a nice white...not so expensive.
     
  7. 7228sedan
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    7228sedan Senior Member

    I personally use a wire brush, compressed air, and a few cans of automotive brake cleaner to prep. I then use standard aerosol engine paint. As long as the grease & grime are removed correctly, and enough paint put on it will last.
     
  8. michael pierzga
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    michael pierzga Senior Member

    Yes indeed. Brake cleaner is a fantastic degreaser.

    What is the chemical in Brake cleaner ?

    When used in the engine room will it give you the herky jerkies....like Triclorthelyne ?












    e
     
  9. 7228sedan
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    7228sedan Senior Member

    Wouldn't you agree that a proper ventilation system would be required when using any kind of solvent, or any aerosol for that matter? Unless the "herky jerkies" was your goal of course ;)
     
  10. michael pierzga
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    michael pierzga Senior Member

    Sure proper ventilation is required... but, Just like Beer needs to be cold before drinking. ... the world just aint perfect
     
  11. sdowney717
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    sdowney717 Senior Member

    I have good results with Rustoleum enamel spray paint on engines.
    Primed then painted.

    I actually clean with a strong solvent if real greasy such as E10 gasoline using a paintbrush or a scrunge, spray it off with a water hose, then I clean with water and dish soap, whatever it takes to get whatever is on off of the metal.

    E10 with the 10% alcohol mixed with gas makes for a very good cleaner. Just do not make a spark. If the engine were inside a boat, I would not use gasoline to clean anything!
     
  12. Leo Lazauskas
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    Leo Lazauskas Senior Member

    I don't know, but I remember bleeding brakes on an old Number Super Snipe I
    owned and getting a mouthful when I shouted out to my friend to start
    pumping the brake pedal.
    It's a taste you never forget, so it might have the same ingredients as are
    found in Bud lite :p
     
  13. PAR
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    PAR Yacht Designer/Builder

    Leo, that must have been a DOT 3 brake fluid, as the DOT 4 hasn't sufficient enough hops to make it taste like BudLite.

    I've had regular aerosol enamels burn or discolor on engines previously. This is why I use the high temperature engine enamels. There's two kinds, one tolerates up to about 400 degrees, before it starts to burn, which is usually fine on a wet exhaust equipped engine and the other is good for a few hundred degrees more, which is what I use for automotive or other dry exhaust engines. Simply put, you can paint the one version on a BBQ and it'll burn right off, but the other will not.
     
  14. brian eiland
    Joined: Jun 2002
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    brian eiland Senior Member

    Cleaner, Degreaser

    Brake fluid is awfully corrosive and penetrating to be utilized as a 'cleaner/degreaser' :!: I would also be concerned with it attacking some of the rubber and plastic parts that might be attached to the engines,...hoses, etc.
    ...and it is petroleum based.

    Why not use one of the newer water based cleaners such as
    1) Simple Green
    http://industrial.simplegreen.com/

    2) Super Clean
    http://superclean.com/
    (I've hear glowing reports about this one, even as a safe, effective paint stripper)
     

  15. 7228sedan
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    7228sedan Senior Member

    Not brake fluid, brake parts cleaner!
    Simple green and the like are great degreasers. That being said they are not ideal for paint prep on engines. Brake parts cleaner evaporates in seconds leaving behind an oil free surface ready to accept motor paint. Simple green requires a water rinse. Painting with oil based paint where a water wash has taken place can greatly reduce the desired effect.
     
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