Bottom Paint and other bottom questions,..

[chariotdriver]

When we first got the 2002 40 Open we had to pull it out to swap out a dinged up prop from the previous owners as we could not get it off under water.
While it was out I asked the boat yard if they could pressure wash the bottom and the gentleman walked up to the boat and rubbed his finger on the bottom paint (teal color) and said that if he did it would all come off as just rubbing it with his finger was removing the paint almost like you would imagine like an artist water paint would do when whetted a little and then rubbed with your finger. The boatyard man said it looked like sometype of sailboat paint he has seen in the past, does this sound possible?
So we opted to not pressure wash it and just replaced the zincs on the shaft and that was all. We could not see any place to put zincs on anything but the shafts. I just had the bottom cleaned of barnacles again and also had the zincs replaced. The diver said that there was not anyplace to put a zinks except the shafts. I thought that there was suposed to be a place to put them on the rudder and and maybe the cutlass support.
Sorry for not being more familiar with the proper terms, new to this.
So I want to repaint and would like to do the best job and do not want to rely on just a local persons opinion and wanted to find out your opinions.
The boat is located in South Mississippi on the GulfCoast.
Thanks,
Phil

[Martuni]

I have the same boat (year and model). Congrats on your purchase. There are actually 5 places for the place of zincs, the shafts, the trim tabs and the transom. I recommend doubling up on the shaft zincs. Each trim tab gets a R4 rudder zinc. The transom has two through-hull bolts in the center of the transom about half way down the water line to the bottom of the hull. This is for a hull plate zinc. There is a size that fits these bolts but I just use a divers plate zinc as they are easier to find and do the job.

More important than the hull zincs are your engine zincs. I have Yanmar 6cxm-gte engines in my boat. Each engine has 12 pencil zincs that should be replaced annually. These engines are big $$$ and you should do all scheduled maintenance and replace zincs at recommended intervals or when visual inspection shows 60%+ wear.

As far as bottom paint goes, all ablative bottom paints will rub off slightly onto your finger when you take the boat out of the water. However if the paint is real soft, I would suggest power washing the boat, letting it dry and then giving the bottom a good sanding with 100 grit paper on an orbital sander. You want to take the soft paint off but not the primer. This is a big job and will take a day or so to do it right. When finished sanding, rub the bottom down with a solvent cleaner designed for that purpose. They you want to apply two coats of ablative bottom paint. Depending on how often you paint the bottom you want to use either a 45 or 65 % copper content with antifouling properties. I paint my bottom annually and this year used Blue Water 45 SCX. It appears to of held up great thus far. Here is a link to a site that carries it http://www.boatzincs.com/blue_water_bottom_paints.html

West Marine had a good bottom painting tips video on their website. Not sure if it is still out there or not.

[flbluerunner]

I have a 1996 and a 2006 38 Open.
The 1996 also has zinc's on the rudders, the 2006 is an IPS boat so totally different.
I agree fully about the motor zinc's.

Good luck

[flbluerunner]

I forgot to mention that I am having excellent success with Sea Hawk Biobor TF.
I am getting about two years out of a paint job.

I am also using Prop Speed on all metal, it is a pain but works great.

[witeagle]

I agree with what everyone said here - you have at lease 5 zincs under the water line. You also need to replace the engine zincs. Once a year should be enough.

BTW - if one of them breaks off a from the brass fitting and you can't get it out but can see part of the old zinc still stuck in there, a wet dry vacume will usually suck it right out.


Bottom paint -

since you really don't know what is on there, you should really sand and repaint. I have been using pettit horrizons up here in NJ. You may need something else down there.

[HisDoghouse]

I've got a 2004 38 Open, and I only have zincs on the shafts and on the stern. Everything else is bonded together and to that stern zinc.

Joe

[CaptainJR]

Flbluerunner,

Are you using Propspeed on the thru-hull metals too, or just props/shafts/struts?

[flbluerunner]

So far i am using it on the IPS pod and the props.
I'll probably do the thruhulls next hull out.

John

[chariotdriver]

Hey thanks for the info,..
Not sure where the engine zincs are located but will start to look.
I forgot to mentioned the zinc on the transom as I have that one also.
My brother had a idea about placing some zincs in the sea strainers for the engine.
Thanks,
Phil

[HisDoghouse]

Phil,

Look inside your boat. If you've got a wire connecting all your thru hulls together and it goes to a bolt on your transom, you should be covered (as long as the connections are good w/o corrosion). That wire is bonding everything to the one zinc on the back.

Depending on which engine you have, the zincs will be all over the place. On my 6CXM-GTE2's I have 12 each.

Joe

[witeagle]

Your engine zincs are scattered around. Best places to start looking are in the heat exchangers, exhaust elbows, transmission coolers and anyplace else your raw-water flows in your system.

[CaptainJR]

So my 6LY3-ETP's have only two engine zincs each. I can't imagine keeping up with 12!

[Martuni]

My Yanmars have 12 pencil zincs scattered around the engine. Six are easy to find at on the intercooler, 2 at the rear of the heat exchanger, 2 at in the front of the engine and the other two are on the lower port side of the engine (if my memory serves me correctly). If the engine has not been painted over, Yanmars have red and white zinc stickers on each zinc bolt. In addition, the zinc bolts are all one size that is only used for the zincs on these engines.