Painting an outboard gearcase, but there's a catch....

[Guest]

I'm not sure where to put this post, but this seems as good a place as any. I've had great luck with the advice from you guys this forum so far. (are you listening WoodonGlass?)

So here goes:

I just picked up a 2004 beautiful Evinrude Magnum (M-1) gearcase to replace the original worn out gearcase on my 200 Evinrude OceanPro.

Its a freshwater unit, and the OMC dark charcoal paint is in almost perfect condition. no fading, chips, corrosion or bare spots.

My motor is white, and I want to paint the gearcase white to match it, but I want to do it right.

Some questions:

How do I prep the this existing finish for the color change? when the existing finish is in great shape?

Do I need to sand and prime over this original paint?

or, can I sand the existing paint with maybe a 400 grit sandpaper to etch it, and apply the OEM white paint?

I've done many outboards and drives with rough/worn/weathered/bare/corroded surfaces, but never one that's good to begin with.

Thoughts?

 

[dezmond]

I would sand then primer with light grey or white primer just so you have an even colour. White over black is a pain to cover.

Just my 2 cents.

 

[gm280]

If you are gong to do this right and have any hope that the new paint will stick, you have to sand the "near perfect" finish that is presently on it. And I would sand it and prime it as well. Why, you may ask? Because you have no idea what type paint or other finishes (waxes or sealers) that are presently on that section.

So sanding will remove the finish in prep for prime. The primer then acts as a quality sub-straight for the new paint. And as stated above, go with a light grey sandable primer. And if you get any issues, wet sand the primer for the best finish. Then color match the engine paint and spray it to match. JMHO

 

[Woodonglass]

Ditto. Make sure to wipe it down after sanding with Acetone. Also I'd recommend 220 grit. It will give the Primer a bit more "Bite" surface. If you use the Rustoleum Formula, I'd recommend 2 coats of Primer and then the Paint with Hardener. That's what I did on my 85 hp Johnson and it still looks new today. Course I haven't got to use it much!!!:facepalm:

 

[mickyryan]

sand to 220 then use epoxy primer to seal the existing material then use a urethane 2k paint sprayed thin coats 2 to 3 to be safe since it does get abused, any decent automotive paint suppy will have , ppg delfleet essential is a good one .

 

[chevymaher]

I would sand it to metal. Then the chips and you will get them. Wont be screaming look at me as you trailer.

 

[Guest]

Guys:

I don't have a compressor and spray gun to use the 2 part paint with hardener, or I surely would,
And I sure don't want to brush that stuff on ( I've seen that done on motors, and the finish looks awful - brushmarks.)

That being said, I can sand it easily enough with 220, to etch the existing finish as WoodonGlass precribes,, but what brand of Spray Primer should I use?

RustOleum Professional makes a light gray Aluminum primer (which I'm aware is not going on direct aluminum).

I also happen to have a quart can of 2 part (white) Epoxy Primer (for that hull/roller repair that WoodonGlass was helping me with). Could I roll that Primer on the Lower unit with a foam roller and sand it?

GM 280 - What grit should I use to wet sand the primer with?

I plan to sand between the white finish coats with maybe 400 grit. I don't want the paint coming off when I remove the flushing muffs...

WoodonGlass - I have a Tractor Supply Store nearby if you have any ideas for primer/paint, I just don't have a means to spray it.

 

[fishrdan]

Be extremely careful cleaning around any openings that have been exposed to oil, and don't drag oil residue from those openings onto the area you're painting. I had that issue while painting my drive, because I wasn't "careful".

 

[Scott Danforth]

Get a preval sprayer and a few extra cartridges to spray 2-part paint without a compressor

 

[gm280]

CaptErich, I usually use either 400 wet/dry paper. or even 600 wet/dry paper when sanding the primer. But use it with water.he helps allow the sandpaper keep from plugging up and washes the loosen primer off the item. You wil be really amazed at how smooth the primer will get.

I realize you don't have a compressor to do this. But seriously, do you have a friend that has even a very small compressor (pancake type will even work) you could use? I ask because it really will come out light-years better with a typical HVLP sprayer. Even a cheapie Harbor Freight HVLP touch up gun will work. And they sell them very cheap! JMHO

If you have the time, take a look at my Johnson Engine rebuild thread (linked below) to get an idea how it is done.

 

[zool]

Some NAPA auto parts stores will mix any auto paint code in either single stage or base/clear in rattle cans for ya.....I use them for small repairs and bumpers when i dont want to dirty a gun or run to the jobber.

Around 20 bux a can for base and clear and 24 for SS.

 

[JASinIL2006]

Preval is the way to go. My ACE hardware carried it.

 

[Guest]

GM 280, The thread for your Johnson Engine didn't come through. Please send it again, or PM me.

 

[gm280]

GM 280, The thread for your Johnson Engine didn't come through. Please send it again, or PM me.

The link I was referencing is in my posted comment at the bottom. Here it is;

'76 40 HP Johnson rebuild https://forums.iboats.com/forum/engin...mplete-rebuild

 

[Woodonglass]

I'd use the Rustoleum Grey Bare Metal Primer. As GM said your final sanding should be 320-400 grit. The Preval system IS a economical and practical system for small area. Home Depot and Lowe's both carry them You can roll n roll and or Foam brush on the two part paint but sprayin IS the way to go Preval let's you spray for under $20 bucks. All the other suggestions ARE great and will work. As EVERYONE knows I'm a C.O.B and really like the Rusty System!!!

 

[Guest]

I did some reconnaissance at few local stores this afternoon, just to see what was available to me. I checked out some Rustoleum "Professional" Aluminum (light gray) Primer , for bare metal and previously painted surfaces. They also had just regular gray primer (also Rustoleum professional. They were in rattle cans,

The Autozone I went to had Rustoleum "Sandable" high build Primer, but since I have don't have poc marcs or damaged surface spots, I think the Gray Aluminum Primer from Home Depot will sand just as well.also in rattle cans.

If I sand the existing paint finish with 220 or 320 as WoodonGlass says, and lay down two or three coats of the (Aluminum) Primer, then wet sand it with 400, I think I should be in good shape for the top coat. ( let me know if I'm off track here)

I did some research on the Preval paint system, which looks like a good system that might be just right for painting the gearcase and upper leg.

Now I have ask you guys what 2 part paint you would recommend.

I've used Interlux Brightside 2 part Polyurethane before, its a nice 2 part paint, but I'm not sure if that would work too well on an outboard, (its a topside application)

I want something gloss white that I can simply mix the color and hardener and go to it.

GM280 - what was that PPG "Line" 790(?) black Paint, that you used on your '76 J40, just a 2-part mix? Did you clear coat that motor? (The PPG paint site has like 20 different paint lines, and they can get as elaborate as you like, I want simple and durable)

Can I use an Automotive finish?

Woodon, what 2-part paint did you use on your Johnson 85?

This motor is going in saltwater, and will be boat lift stored, and I need some ideas, guys, Thanks!

 

[gm280]

CaptErich, I used PPG Shop Line base coat, clear coat finishes. The Black number is 9700. The clear coat is JC630 or JC631. There are a lot of different types paints, but those are very easy to mix and spray. I used standard lacquer thinner, and carb cleaners, for clean up of gun and such. But NOT in the PPG paints at all. The hardener is the only additive I used. You buy that per temps you will be spraying, but the medium is the standard for most of the time. The paint will tell you what mixture to use and the proper thinners as well. Pretty hard to mix it up wrong when using the mixing cups.

Yes the 40 HP Johnson engine I rebuilt was clear coated. And it really looks very glossy. And it is also totally impervious to any fuels, oils and gas.

I used Zinc Chromate on the bare metal, then primer on that followed with 9700 base black coat with JC603 clear coat for final. Hope that helps. And you can buy any PPG paint in the pints if you like.

 

[Guest]

Thanks GM 280. that clears up a lot.

Did you use the Etching Primer or two part exoxy Primer? or both?

By the way, do you still habe that 76 Johnson 40, I loved those old 40 big twins, they were pushing a lot of heavy lobster and clamming boats when I was a kid.

here's what whay my 1973 looked like back in high school, had it on a 16' Lyman lapstrake

 

[gm280]

Thanks GM 280. that clears up a lot.

Did you use the Etching Primer or two part exoxy Primer? or both?

By the way, do you still habe that 76 Johnson 40, I loved those old 40 big twins, they were pushing a lot of heavy lobster and clamming boats when I was a kid.

here's what whay my 1973 looked like back in high school, had it on a 16' Lyman lapstrake

Yes I do have the 40HP Johnson. It is scheduled to sit on the back of my boat, if I ever get the boat finished.

I used Zinc Chromate primer. Etching primer can be used in place of Zinc Chromate. I just used ZC because I used it a lot many decades ago when I was still working. I figured that if the government used ZC on their bare aluminum air-frames, it has to be the best method to use. It is great for bare aluminum. But Etching primer can be used equally as well. Then you can use a good quality two part primer on top of that etching primer.

I used PPG K36 primer with K201 hardener/activator. But there are probably better PPG 2K primers now. Just stay with one produce line when painting anything. That is the safest way to keep everything working together properly.

After you get it primed, wet sand with 400 or 600 until you like what you feel in that primed finish. Then top coat with whatever method you prefer. I went PPG base coat followed with PPG clear coat. And if you seriously want a show room finish, polish that clear out after wet sanding with 2000 grit paper and a quality polishing system. You won't believe your eyes. I used the 3M polishing materials.

 

[Woodonglass]

Rustoleum with the Hardener IS a two part paint. I used it and it's Hard as nails, resists the Oil and Gas spills and is holding up well. I just don't see why it's necessary to pay the extra expense for the other paints. My Rustoleum is holding up extremely well.