Prep and paint for the LU

[Mandrake35]

Re: Prep and paint for the LU

The camo reed look is pretty easy, I just cut some thin slots in some plastic....you know the packaging that everything from china comes in?? Its pretty sturdy so I use that. I have a few with different #s and lengths of reed. I also use the hotdog shape cut out for the cattail look. I also hold leaves and branches and spray over them. If you do camo it helps to go from light to dark colours. Its not a look for everyone, but I have a 65 9.5 sportwin, and in my opinion its kind of an ugly motor anyway......it sure is reliable though. Have fun and prep prep prep

 

[dewdiggler]

Re: Prep and paint for the LU

sorry oldrudedude im so late on the responce.

do a search for ZING HULL CLEANER and it will show up.
its in a white bottle, cost about 8 to 9 bucks and worth every penny.

 

[oldrudedude]

Re: Prep and paint for the LU

This is what I have done so far. If one or all of these steps seems inappropriate, please let me know. I may be able to correct it.

I removed the old paint and heavy corrosion with a 80 grit sanding disc on my electric drill. 80 grit turned out to be a little too coarse. 120 would have been better.

Wire wheel on my drill to get into the nooks and crannies and better clean the pitting. Once the grey oxidized layer under the paint was sanded away, it became obvious that the whole area I intend to paint is moderately pitted.

The pitting is a concern to me because I wish to prevent/retard future corrsion. To better penetrate the pitts, I next used rust remover gel from an automotive store. This is phosphoric acid. My intention was to erode and wash the oxidized aliminuim from the pitts and create an anodized protective coating on the parent aluminium.

After two application and rinsing I noticed water beading on my not yet paintable surface. Must still be oil on the surface. Several applications and scrubbing with cheapo spray detergent and no more water beading.

Two more applications of rust remover and extensive rinsing and I think I am almost ready to prime with zinc chromate primer.

Now if it will just stop raining........

 

[AndyD]

Re: Prep and paint for the LU

Sounds like you did a real thorough job. If you want to just to be sure you can wipe with lacquer thinner just prior to painting. It evaporates fast and you will be sure to have a real clean surface.

Also, I'm not sure how phosphoric acid reacts with aluminum. It's usually used on steel which has a different electrical charge. If it were me I would make sure that it was all completely washed off after cleaning the metal with it. It could counteract what the zinc is supposed to do as far as corrosion inhibition goes. I might be wrong on this but that is my gut feeling and my 2 cents worth.

 

[oldrudedude]

Re: Prep and paint for the LU

Also, I'm not sure how phosphoric acid reacts with aluminum. It's usually used on steel which has a different electrical charge. If it were me I would make sure that it was all completely washed off after cleaning the metal with it. It could counteract what the zinc is supposed to do as far as corrosion inhibition goes. I might be wrong on this but that is my gut feeling and my 2 cents worth.

I sent about three hours yesterday researching it on the internet. Seems phosphoric acid is pretty standard for anodizing aluminium prior to priming with zinc chromate. Washing laquer thinner sounds like a good idea.

 

[jbjennings]

Re: Prep and paint for the LU

If you do it right, it will stay on the lower unit unless you're hitting stumps and such and chipping the paint off. If you do it wrong, it will peel off in 2 or 3 trips. I try to leave the old paint on the metal as much as I can because your new primer will stick to the paint a lot better than it will ever stick to aluminum. One of the best couple of lower unit paint jobs I ever did was with duplicolor primer and paint. It seems to hold up really well. I also did a mercury with $.99 paint from walmart with automotive clear and it looks as good as factory with several trips through nasty water on it. But most of the old paint was still on the lower unit on it.
I prefer acetone for my final cleaning before primer. Let the primer dry really well and sand it before your first coat. I do it even if the primer says you can topcoat it without sanding.
Good luck,
JBJ

 

[oldrudedude]

Re: Prep and paint for the LU

Unfortunately, there wasn't enough paint left on the LU to salvage. The paint was basically gone with a lot of pitting up to within 6 inches of the top of the mid section. At this time my prime enemy is the pitting. All the washing and the wire brushing has not been able to get the corrosion out of the bottom of the pitts. I fear, if I paint over that corrosion, the paint will bubble no matter what kind of paint and primer I use. I really should invest in a sand blaster and do the job right. The weather has turned foul though, so I may not be able to finish this job until spring anyway. That sucks.

 

[Mandrake35]

Re: Prep and paint for the LU

I'm wondering how long til someone Masks off a lower end and hits it with rhino liner........sorry, thought you could use a laugh.

 

[oldrudedude]

Re: Prep and paint for the LU

What's the joke. That's a great idea! Or how about a polymer dip tank? Sounds like a good business opportunity! OK, I'm in!!!

 

[oldrudedude]

Re: Prep and paint for the LU

We finally had a couple of good weather days. This is the final result after the top coat. The pitting is still quite evident. Perhaps I should have sandblasted and filled with epoxy before priming. I will find out in the spring how it stands up to water and weather.

 

[bktheking]

Re: Prep and paint for the LU

Looks good, you can't really get away from the pitting unless you fill it with an aluminum body filler and sand it down till it's smooth. At this point though are you trailering the boat and motor to boat shows???? Not trying to be a smartass but almost all that i've redone that are going to be used and not on a stand have pitting, you can't get away from it if it's a "daily driver" so to speak.

 

[oldrudedude]

Re: Prep and paint for the LU

I use zinc chromate primer and OMC paint and all the metal parts of my motors and they turn out really well.

BK, where do you get your OMC paint? Searching on line found this site:

http://www.nymarine.ca/index.html

Area code 905 so appears to be in the TO area. Handy for me.

He has older OMC colors in aerosol.

I have a '71 Evinrude 50hp I would like to repaint in the spring.

 

[bktheking]

Re: Prep and paint for the LU

The dealer about 10 minutes from my house called John's Marina has a rack full of paint, do you have a part number? I can give them a ring and find out.

 

[asdasc]

Re: Prep and paint for the LU

Oldrudedude, what would cause it to pit like that? I leave my outboards in the water all summer long and have never seen that. I am all freshwater. Was this is salt water? I would hope to not have to start raising my motor everytime I get off the pontoon boat.

 

[oldrudedude]

Re: Prep and paint for the LU

Dealer? Didn't think it would still be available through the dealer. Closest dealer to me is over an hour away. Thanks, but I'm not going to worry about it until spring.

 

[bktheking]

Re: Prep and paint for the LU

Yes most OMC dealers carry motor paint, I even bought "powerhead" black paint for my 83, they had a whole assortment of powerhead paint colours (not the spectrum mind you).

 

[oldrudedude]

Re: Prep and paint for the LU

Oldrudedude, what would cause it to pit like that? I leave my outboards in the water all summer long and have never seen that. I am all freshwater. Was this is salt water? I would hope to not have to start raising my motor everytime I get off the pontoon boat.

I don't know what the history of the motor is. It was part of one of those "free boat and motor, just get it off my trailer" deals. The interior of the boat is totally rotted out. My guess it was left in the water with the lower leg down and neglected for a long loooong time. There is no salt water within a thousand miles of me. The old service sticker is from a local dealer..... but who knows. The paint on the upper part of the motor is in fairly good condition with no corrosion. Not what I would expect from long term exposure to salt water environment.

I have never seen salt corrosion on a motor so I don't know. I wish this motor could tell me a story.

 

[oldrudedude]

Re: Prep and paint for the LU

Yes most OMC dealers carry motor paint, I even bought "powerhead" black paint for my 83, they had a whole assortment of powerhead paint colours (not the spectrum mind you).

Cool!

 

[gbb]

Re: Prep and paint for the LU

I'm getting ready to do my lu, what brand primer and where did you find it. I looked at Home Depot and True value but can't find a zinc chromate primer

 

[bktheking]

Re: Prep and paint for the LU

This is the stuff I used:

And before anyone asks, no that's not my can