Engine and ER Painting Techniques

[52CMY]

My 8V92TA Engines are almond and my ER surfaces are grey and need a repainting. The oilpans and undersides are in the worst shape.
Current plan is to cover the hoses/wires in aluminum foil and tarp the bilges & decks. remove the AIRSEPS and cover the inlets. Run room fan for ventilation. Clean the painted surfaces with with wire brush, sandpaper, and maybe ospho the badly peeling oilpans (I've never used ospho). Vacuum and wipe down with spirits/acetone.
For paint, I'm planning to use Rustoleum and apply with brush and/or gun after thinning. I understand rattlecan spraypaints don't yield good results.
My questions are: Has anyone used an airbrush or found a compact airgun or airless paint gun useful for tight quarters? If so, what brands/models/attachments are recommended?
What can I expect for fumes or other hazards assuming I have fans running?
Absent finding a smaller person to lay in the bilges under the engines, is there a directional paint nozzle system that works to spray around tough to reach corners?
Assuming I use Rustoleum, should I prime first?
Should I pull the engine room salon hatches or use them to block overspray to rest of boat. I really don't know what to expect.

 

[52CMY]

Some YouTube Videos say the key to paint adhesion to bare case iron is to heat the surface with a heat gun or a torch to evaporate moisture, the wipe down with acetone. Is that actually required?

 

[Briankinley2004]

Somebody recently posted a link to R A Clarkson's painting thread. He did it the correct way and stripped everything bare. If you can find that thread I would read it. I did my engines with POR but did not strip down. I removed loose paint, sometimes to the bare metal, and primed bare areas with POR rust primer then top coated. Mine does not look as good as Mr. Clarksons but is miles ahead of the rattle can job that was on it. It aggravates me to see hoses with overspray all over them. At least I didn't get that with the POR. I used small chip brushes mainly.

 

[Bob Quinn]

Somebody recently posted a link to R A Clarkson's painting thread. He did it the correct way and stripped everything bare. If you can find that thread I would read it. I did my engines with POR but did not strip down. I removed loose paint, sometimes to the bare metal, and primed bare areas with POR rust primer then top coated. Mine does not look as good as Mr. Clarksons but is miles ahead of the rattle can job that was on it. It aggravates me to see hoses with overspray all over them. At least I didn't get that with the POR. I used small chip brushes mainly.

POR is amazing stuff. Stops rust. might be worth researching. $$$$ I've used on on some edm machines in areas that got wet and were starting to rust. It almost seems like it makes a very hard tough glossy coating, at least in the black gloss color I used.

 

[52CMY]

I had not heard of the POR brand. Thanks for the recommendation--I'll look into it.
Any thoughts on sprayers with that could ease getting under and around corners? Or is the brush the way to go?

 

[rustybucket]

I had not heard of the POR brand. Thanks for the recommendation--I'll look into it.
Any thoughts on sprayers with that could ease getting under and around corners? Or is the brush the way to go?

If you have all hoses covered in aluminum foil and paint blankets over floors/walls...etc there is nothing wrong with a good rattle can. Rustoleum Industrial seems to hold up very well and you can get in spray can or normal paint can. Some spots are almost impossible to get to with the brush.

To clean the engines we used evac fans to pull a good cross flow of air out of the engine room. Then we mainly used brake cleaner to 'rinse' off the engines. Kinda amazing how much gunk/oil/grease came off of relatively clean engines. Under the engines we had pig mats to catch all the runoff.

After brake cleaner had evaporated and thoroughly aired out we went straight to paint.

I did run a heater in the ER the night before paint as well as the night after to make sure no condensation or cold metal would ruin the paint job.

 

[jim rosenthal]

POR-15 is a very tough paint. It is a moisture-cured urethane product; the water vapor in the air is what makes it cure. It is impossible to get off your hands (ask me how I know) As long as you are not putting it on something that will be exposed to UV, it will outlast all of us. In areas exposed to UV, it has to be topcoated to prevent UV damage. POR also make a series of engine paints which are also very tough.

The only thing that concerns me about your initial plan is that you should make sure you have enough brisk ventilation and that you do not work in the engine room alone. Especially when using volatile products like Brakleen, fume levels can build up very quickly and cause you to lose consciousness. Getting a limp unconscious person out of an engine room of a boat would take two or three people to do a dead vertical lift, with every second counting. To avoid this kind of situation, you will need a lot of ventilation and to make sure you are not working alone, ever.

 

[johnjen50]

Also a good 3M mask, like the kind you use to paint awlgrip, is good insurance you don’t hurt yourself.

 

[jmooney]

To clean , I have used formula 88 , like purple power , used full strength, it almost eches the old paint . I have had good luck with Krylon . Preparation is key and using a good primer. All this is with spray cans . Everything has to be covered with plastic. Walls , bilge , etc. I have used a strong vacuum connected to a cardboard box with an air conditioning filter attached to one side. A good respirator is mandatory.

 

[rustybucket]

POR-15 is a very tough paint.

Did you use the POR-15 engine paint or just regular POR-15?

 

[Briankinley2004]

Did you use the POR-15 engine paint or just regular POR-15?

I used the engine paint on mine along with their products for degreasing and metal prep

On the exhaust manifolds it burned off on the cylinder connections. I sent photos of it and they did some research then sent me some free manifold paint that is rated for higher temps. It has held up ok but not like the rest of the paint. I have had to re-apply it and it probably needs another coat now. Luckily it is a small area but I have 24 of them to do.

 

[rustybucket]

I used the engine paint on mine along with their products for degreasing and metal prep

On the exhaust manifolds it burned off on the cylinder connections. I sent photos of it and they did some research then sent me some free manifold paint that is rated for higher temps. It has held up ok but not like the rest of the paint. I have had to re-apply it and it probably needs another coat now. Luckily it is a small area but I have 24 of them to do.

Good deal, just got some on order, gonna give it a try. Yeah, I tried hi-temp brake caliper paint on the exhaust manifold sections without water jackets and it burned off very quickly. I'm not sure anything is going to hold up in that area, just too much heat.

 

[jim rosenthal]

Did you use the POR-15 engine paint or just regular POR-15?

Regular POR15.

 

[52CMY]

Thanks everyone for your inputs! Good info. Definitely will watch out for respiratory and fire/explosion hazard with volatile solvents and paints.

 

[jim rosenthal]

Post photos if you are able to. Seeing these projects move along is always encouraging.