Detroit Diesel Valve Cover Clean Up! Boat Bling on a Budget.

Introduction: Detroit Diesel Valve Cover Clean Up! Boat Bling on a Budget.

   I am currently helping restore A 73 ft Alden MotorYacht in So-Cal. The Main Engines are GM Diesels ( AKA Detroit Diesel)
 12-71NA These 2-stroke slobbering Beasts are Rated at 550 HP @ 2250 RPM. The Vessel can "Sprint" to 16 Knots and Cruises
 at 12 Knots. This instructable focuses on a cosmetic repair that can be applied to many items on a Boat.

        One thing about boat engines seem to be common, A coat of paint can make an Engine look New! This Vessel was
Launched in 1959 and had Many " New" Coats of Paint. The appeal of the GM/DD Green gave the Engine Room A bland look
 and wanted to spiff it up! Had a slow week while waiting for parts to trickle in, ( Working with a Non-Profit.)

Step 1: Options...........And Safety

  Pulling of the Valve Covers and dropping them off at A chrome shop would be great, Having them powder coated would be to,
  The Budget allowed requires more sweat equity than $$$.

  So. Scrape Strip them and Paint.

   Warning!!!  This is a Guide, Safety is up to You, This involves Hazardous chemicals, Scrapers, and Powertools, I am
Held harmless from damage to items, damage to yourselves or Boats, Animals, People,Trees,Water and Rocks.


   Scrapers, These where not to sharp to prevent gouging the stamped steel
   Sandpaper, These are stamped steel so I did not use anything less that 120 grit.
   Wire Brushes, toothbrush size SS ones are great but tend to scratch lesser metals
    Drill with wire wheels, Or a Grinder with a brass wire wheel ( please use a grinder safely, even small ones
   can tear a chunk out of you quickly, If you are not experienced with on please stick with the drill
   Green Scotchbrite pads ( I even used some of the silver ones to finish prep and in between coats.
    Scrap wood, small sticks are good to get into hard to reach places.
    Small plastic cups, throwaway brushes (1$ store)
     I  keep a  bucket full of water just in case I get any stripper on me. last time I got
     some stripper on me I had an itchy rash for weeks.......!!
    Plastic drop sheet, Newpapers, to catch and Properly Dispose of waste.
     Some "green" or "purple" cleaner, I have found some at 1$ stores nearly as effective
     I have found there green scrubby pads good also.
     Acetone, nasty stuff but is good for final prep.
     Paint: I usually use a premium engine block hi-temp sold at body shops the best,
      On a budget your local auto parts store, Try to get one that has ceramic in it. These
      are large valve covers so I was able to use one can each to get 4 good coats.


  Paint Stripper:.....

Everyone knows that paint stripper is dangerous. If it wasn’t dangerous, it wouldn’t be able do what it does. There are a few common sense precautions you can use when working with or around paint stripper.

Respiratory Care

Paint stripper is a volatile organic chemical. This means among other things that it’s flammable. This means that when using it or working near it, you should take all common sense measures to keep the fumes from being ignited. It also means you should only use it in a well ventilated area. A respirator mask is highly recommended. If you can’t get one, then at least a high filtration particulate mask is in order.

Personal Protective Equipment (PPE)

PPE is defined as any piece of clothing or equipment that is required to prevent or minimize bodily harm. Some things that fall in this category in regards to paint stripper are as follows:

  • Eye protection—This should at least be safety glasses, but a mask or goggles are better in protecting against splashes.
  • Clothing—Long sleeves and pants are important, especially for those with sensitive skin.
  • Rubber Gloves—If your exposure to the paint stripper is going to be for longer periods of time, you should wear gloves to protect your skin from burning and rashes.
             There are many less harsh strippers out they unfortunately not as effective and cost more.

Read more:

Step 2: Scrape, Peel Back Time.

   I had originally planned to use stripper down to bare metal but you can see above how thick paint this was. 

Tools Needed:
  1.   Scrapers ( The Valve covers are stamped steel, slightly dull is good)
  2.  Heat Gun
  3.  Tarp/Drop Cloth  ( For waste )
 Above tools are for Stage One.
  I worked on medium heat, I wanted to soften rather that bubble off the paint
 Working the heatgun  evenly to not distort the valve covers. Be careful where you set
  the heat gun down, I have a brand in a place I never wanted it ! not to mention it is a
  fire hazard. I came across a ceramic oval planter to act as a holster for it.  Unfortunately
   it met its fate from being pulled to a shattering end from the power cord pulling from its bench.

   After you can no longer scrape with the heat gun its time to go to stripper.

  Stage Two Tools:
  1.   Personal Protection ( Face Shield/Goggles/Gloves)
  2.   Paint Stripper
  3.    Qt Cup for stripper, throw away brushes
  4.    SS Wire Brush
  5.   Green pads, Rags
  6.   Water Bucket

Step 3: Stripping

 When stripping I usually concentrate on small areas, There is about 6-inches between the hold-down bolts.  Apply stripper
from a cup and brush, let sit, can vary due to temperature ,paint and time. The knobs and lettering took  the most time.
 The lettering was where I used small scraps of wood. I also used some plastic scrapers to muck the residue into a waste can.
 I spot stripped it down and used the green scrubby I rinsed it off with cleaner and finished it with a wet sand with silver scotch
brites, one more rinse and let dry over night.

  Sorry no pictures, nasty stuff I did not want to get my camera near.

Step 4: Final Prep and Paint.

 I wipe it down with acetone and let dry while mixing the paint for 10 minutes.

    Applying the paint is ones personal journey, To me Painting is an Art, Not work, By Brush,Spray,Sponge or Catapult.
 like writing with a pen, everyone's unique style comes with practice.

   My technique for spray paint is the following: Think of the spray pattern like a paint brush and you only want the use the last
inch of the 6-8 inch bristles as one would with a brush, even smooth strokes. And if you start painting happy clouds, stop
immediately and seek a ventilated area. I applied 5 coats and where pleased with the results, 2nd coat had a few sags and runs
so I let it dry overnight and lightly sanded them out with 180 and 220 to blend. The next 2 coats where applied in the Afternoon
Sun with 30-45 minutes in between. Light scuff the next day with silver scotchbrites. Final coat was done late morning after having them soak up some sun, Then I brought them into a improvised paintbooth for the final coat.

  I am putting together several of these Instructables and will be part of my Book " No Cents But Boat Sense"
Also I am plodding ahead with "Rime of The Gen-X Mariner" A chronicle of my Voyages working aboard Tallships the
last 10 years.

 So all you Sailors, Editors, Writers, feel free to broadside me and critique my writing technique!

 Fair Winds and Cheap Fuel,
Mike McV

Step 5: Couple of YouTubes Videos of the 12-71

Step 6: Part 2 Main Engines

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    4 Discussions


    7 years ago on Introduction

    I spent 14 yrs in the US Navy as a Machinist Mate 1st Class. I spent many hours operaring and maintaining GM/Detroit diesels. Even had some that ran generator sets. They were back to back with the generator in between them. The engines could be disconnected via a hand clutch. Many a fond memory there. May you always have fair winds and following seas and may the wind be always at your back.


    7 years ago on Introduction

    Very nice. All the Detroits I was around where work horses and not treated as kindly. Its nice to see a pretty piece of equipment that kept me warm a many rainy days. Your diligent work is well appreciated.


    Reply 7 years ago on Introduction

    If I saw more of your harbor, or that tall ship on the other side of your boat (in the photo), I may be able to call your harbor.


    Reply 7 years ago on Introduction

    Those boats where in San Pedro, Ca at the Time.
    Here is my YouTube Channel with some videos on The 12-71's