Stripping/repainting engine

[trecksail]

Just wondering what's the best way to go about it. Paint remover, soda/sand blast?

[timebandit]

In or out of the boat?
Together or apart?

[Wallilabu]

NEVER sandblast...NEVER...at least not on fiberglass....soda blasting seems to be emerging as a preferred approach for a very smooth job if one can afford it...hand scraping and sanding is the usual way, but care must be taken with the toxic waste...Don Casey's book(s) on sailboat maintenance and repair give very good advice.

[sailingdog]

Umm, you might want to actually read the opening post, as he's talking about how to remove PAINT FROM AN ENGINE. Most engines are not made of fiberglass. Sodablasting would work nicely, with little risk of damaging the parts in question.

Originally Posted by Wallilabu

NEVER sandblast...NEVER...at least not on fiberglass....soda blasting seems to be emerging as a preferred approach for a very smooth job if one can afford it...hand scraping and sanding is the usual way, but care must be taken with the toxic waste...Don Casey's book(s) on sailboat maintenance and repair give very good advice.

[IslanderGuy]

I have stripped paint from car parts a few times with a chemical paint stripper that comes in a spray paint type can, no idea what it was called. It can be purchased at most auto parts stores. I would not say I recommend this over other options as I have very little experience, but I have used it and it worked OK.

However, it is very caustic stuff. You do not want to use it in closed spaces or near hoses and the like. So if you have tha parts out of the boat and disassembled it might work well, in the boat or assembled with hoses or wires near by I would not use it at all.

[tommays]

In my lifetime of learning from FUBAR blasting a motor with any type of media is a bad idea as it WILL get somewhere it does not belong and something will get ground up


Back in school in 1973 we sealed up and outboard powerhead and beaded the case and then washed the heck out it in the safety kleen tank

It ran about 7 minutes in the test tank before the next rebuild

I am painting my mast right now and the hardest part is getting all the dust out from the inside so it does not get on the paint as the mast is rotated so you can see well enough to spray a wet coat of paint

[sailingdog]

Please note, I'm not recommending that you sodablast the engine until you have it in separate pieces. If you're not planning on disassembling the engine...then sodablasting isn't the way to go.

[JHJensen]

Originally Posted by trecksail

Just wondering what's the best way to go about it. Paint remover, soda/sand blast?

Treck,

What kind of engine? How old? In place or out of the vessel? In pieces or assembled? Why are you repainting, is it all rusty or just flaking in spots? Don't like the color ? Does it need a rebuild? What kind of vessel is it in? Can you post some photographs?

You have already gotten some good advice but you need to have a whole plan in mind as it relates to your vessel... not just the engine...it is only one part of a bunch of interelated, interacting systems.

Too much info in this case is good. These are the sort of questions I would be asking if you approached me for advice on how to deal with the situation.

John

[floatsome]

Originally Posted by trecksail

Just wondering what's the best way to go about it. Paint remover, soda/sand blast?

I am just a DIY non-pro looking after one old boat, so take this with a large dose of skepticism, but it seems to be working for me. Our engine was in the boat. I removed all the parts I could and took them into my home shop for close inspection, cleaning and painting. I sent a couple to a machine shop for professional cleaning (manifold).
- I scraped off the grease and flakes, using any hand tools that worked without damaging: flathead screwdriver, stainless wire brush, sharp pick, etc.
- I degreased with detergent, keeping it out of holes and away from parts that may be damaged by detergent; then rinsed with water.
- Continued scraping and brushing as much of the rust as possible. The ideal is to get to bare metal, but that's impossible working by hand at home with an old engine, so I did the best I could. My logic was that if remaining paint resisted removal, it must be adhering pretty good - pros would get down to bare metal.
- Emery cloth helps.
- I vacuumed and used a small air spray bottle from a computer store, to blast clear residue, being careful to keep it out of the inside of the engine.
- I stabilized a couple of rusty areas with a rust stabilizer. They chemically turn the rust to a hard black surface. I never did find one that appeared to excel above the others in googling the net, so finally just used a product at a local auto parts store. Pros would be more informed and methodical. I kept it away from bolt threads.
- Final wipe with acetone, keeping it away from rubber seals and other things that could break down. I wore protection for skin and lungs.
- I picked paints designed for engine heat. The 500 degree brands for all the parts except head and manifold, and the high-heat (1200 degree) brand for those.
- Regarding primer, I never did convince myself primer was necessary, but the pros use it. I checked the instructions that came with the paint brand I settled on (Duplicolor -- it was handy. Pros have preferences).
- I masked off bolts, threads, holes, rubber parts, spark plugs, etc with masking tape and kitchen aluminum foil, and draped a drop-cloth around the engine.
- I sprayed on three coats of paint, being careful to apply the next coat within the minimum/maximum time window in the instructions -- if wait too long, have to wait several days. I set up ventilation and wore a mask.
- Some paints require heat before they harden after drying. Pros do that in ovens, the rest of us let engine heat do it.
- I keep some paint on hand for touchups over time.

[Wallilabu]

Long overdue apology...I admit that I misread the original post and focused only on the paint removal, not the what from...was very focused on a lot of paint removal at the time...sorry! At least now I have a clear conscience..