Rust Protection

[rando]

I have to treat a patch of rust on the base of the tilt/ trim servo.
I am going to give it the treatment with a coarse nylon scour in my drill.

Should I then hit it with a phosphoric acid tratment prior to painting???

I went to the hardware to shop for a rust treatment,expecting to get Tectyl.
They dont stock it.

Is it the right treatment for an area that gets plenty of salt water on it??? If not what should I use??
Bunnings only carry Rustguard & Whiteknight brands of rustproofing and I do not think either is designed for marine applications.
Where will I get Tectyl and is the spraycan stuff OK for this job?

[tunaticer]

Hit up Automotive shops like Repco etc for Tectyl.
Curious exactly what is rusting on your motor....is it the pin and bracket for tilt/trim? Normally most parts on a motor are either 316 stainless or are corrosion protected alloy. If it is the pins you should simply replace them, they cop a fair amount of abuse as you use the outboard.

[Lucky_Phill]

as tunaticer said, automotive shops will have Tectyl... 506 if you can get it.

Spray can stuff is Ok and runs out at about $20 / can.

No exactly too sure on what your treating,,,, it may even be a case of using something like Penetrol first up.

http://www.floodaustralia.net/brochures_guides/pdf_files/Penetrol-factsheet.pdf

and an overview..:"-

http://www.floodaustralia.net/products/paint_additives/penetrol.php


LP

[rando]

The servo motor for the tilt trim system mounts onto the motor bracket ,,, the servo casing and its corresponding mounting plate both show rust. I am worried the rust will invade the faces and compromise the integrity of that seal.
It needs an effective treatment that will stop any progression.
Once I have cleaned the area should i apply phosphoric acid to stop any oxidization then seal with tectyl and paint it ,,, or just paint it with cold galv.

[cormorant]

sand , scour it back to bright metal

Boat shops have engine paints in colours that match

I tend to use epoxies as they are tougher and the pressure pack engine epoxies self prime - well some of them

Follow instructions for your chosen paint system.

I'm not a fan of the rust converters as I'd rather see stuff bead blasted and etched properly or lightly sanded to bare metal, degreased and primed.

tectyl 506 is a wax coating that goes over paint . it is not a paint.

[Roughasguts]

I would go the Penetrol as well it dries after 3 days and can be painted over, it's best under the cowl or painted over once dry cause it's not U/V. But for skegs and such that cop sand abrasion and you wan't it to last! get some 2 pak clear stays on skegs for years.

Cheers

[Dan5]

Is the motor a Yamaha by any chance?......If so i know what your talking about.......We soft sealed the ones we had and then wrapped denso tape around them.

Your pretty much going to have to keep a close eye on it whatever you do and keep some spray/protectant up to it,if it is a Yammy it's a very common problem......

Dan

[Noelm]

I reckon if it has started to rust, there is almost nothing that will permanently fix it, most will help prolong the problem, but in the end it will beat you, clean and paint as best possible, then keep spraying it with oil or some sort of Lanolin stuff to keep it at bay.

[TheRealAndy]

Yup, anything that keeps the oxygen away.

I cover everything with lanox, and respray after everytrip.

[rando]

So I will scour it back to bright metal, spray it with penetrol then cold galv it. and keep the spray penetrol up to it.
Is that the drill???
How long will i have to wait to get it wet once the penetrol goes on,,, surely not 3 days???

[cormorant]

People will differ in their opinion but most cold gal is not that good IMO. It is good in areas where it is never submersed , touching up gates and so on on already gal metal.

Again penetrol isn't a underwater paint undercoat but yep lots use it sucessfully?.

Epoxies properly applies will work , well any paint properly applied to the correctly prepared surface will work.

You have to get the paint ( surface barrier) done properly with a reasonable few coats before you do the wax or grease coatings.

Like others have said it is a bit of a ongoing battle with the metal they have on trim units. Some companies have used plastic and bakelite for years.


Keep an eye on it and keep it repainted and protected as required. They all keep rusting once they start unless you fluke good paint and check out just how much metal has gone as they get pinholes in em and then it gets expensive.


Last one - check with a multimeter you don't have any free current and that your annodes , earth straps are working as apart from shit paint from the factory stray electic current causes very fast corrosion.

[Crocodile]

Hello All,

I used Penetrol on my trailer, used a wire brush in an angle grinder to get it back to almost bright steel, two coats of penetrol and a covering coat.
It was a complete waste of time, the rust came back in short order.
I would not use penetrol for any application.

As for the tilt motors rusting, why the manufacturers cannot fabricate them from stainless or aluminium I cannot understand. It would add a few bucks but on such an expensive item who cares?
There are a surprising number of components made from mild steel on the top brand outboards.

[rando]

Yep Yammie 40 2005 model



Is the motor a Yamaha by any chance?......If so i know what your talking about.......We soft sealed the ones we had and then wrapped denso tape around them.

Your pretty much going to have to keep a close eye on it whatever you do and keep some spray/protectant up to it,if it is a Yammy it's a very common problem......

Dan

[Dan5]

Yep Yammie 40 2005 model

Yep......well known for it they must have done something diffrent in about 07 as they don't seem to have the same issue.
Unfortunatly they are near on impossible to get secondhand because of it being so common.

Look after it with some sort of treatment,look into importing the piece from the US maybe down the track.

Dan

[Fed]

As for the tilt motors rusting, why the manufacturers cannot fabricate them from stainless or aluminium I cannot understand.
I don't know for sure Crocodile but I bet the the motor would be way less efficient with a non magnetic (SS or Al) case so to get an equal output you would need a much bigger motor.

I've had quite a few pretty nasty looking ones but never had one fail from rusting through, I think the cases are very thick.

[rando]

Fed
I am concerned the rust will invade the faces of the flange and mount and cause the seal to fail.
Should i not worry about this ???

[Crocodile]

Hello Fed,
think carefully about the notion of non-magnetic trim motor cases.
All the case does is support the top bearing of the electric motor, it does not conduct electricty.
Some Mercs and Suzukis use a plastic case, and various mechanics have told that they will crack with age.
I have also been told that the steel is thick and takes a long time to rust through.

I have just had this issue with a ten year old 60hp Yamaha.
Yamaha do not supply individual parts(I tried two different agents).
You have to buy the whole trim system $3000.
Second hand from the wreckers about $1500, and is it rusty?, yes.
A Sierra trim motor from the US, $800 but that did not replace the rams which were corroded as well.
New motor after trade about $6000.
What to do?
$3000 for new trim system, waste of money and does not increse the value of the rig.
Used part complete waste of money.
New motor was the way to go for me.
If you take the price of a new trim unit from the new motor a bargain.
Well, relatively speaking, ah,,, B.O.A.T., Bring Out Another Thousand.

[Fed]

I don't think you need to worry rando, give it a cleanup and a good old paint with killrust.
I've run emery cloth around the back (like drying your back with a towel) to clean up and the same method strip of rag to get a few good coats of paint on it.
I wouldn't recommend disturbing it by removal but if you already have then make sure it's well & truly sealed when you're putting it back together.


There will also be permanent magnets fixed inside the case crocodile, I was talking about magnetic flux not electricity.

Seems to me they would be a lot more efficient in a magnetic case, another thing I thought of is the magnetic case may serve a keeper role for the permanent magnets, wouldn't want that flux leaking all over the joint.

I've never seen permanent magnets housed inside a plastic case, are you sure they aren't metal cases coated in plastic?

Where's googleboot when we need him?