Repairing an aluminium prop

Simon Guest · 18 June 2006, 21:01

Having dinged the prop on my Mariner 15 2 stroke (well, having had it dinged by my 8 year old son, but he's still learning, so that's OK), I did a repair job, but not quite as successfully as hoped.

I filed off all the rough bits, leaving a nice clean edge, making sure to do the same thing to each of the three blades, so it remains balanced. Then, simply a paint job to get it as good as new. I used some Hammerite "special metals primer", designed for aluminium among others, and some gloss enamel paint to finish. Looked good as new before it went in the water yesterday.

But now, quite a bit of the paint and primer has peeled off, just as someone warned me, it's tricky to get the paint to stay on aluminium.

So, any tips on better paint stickage? Is there any harm in leaving exposed metal? (The engine is stored dry, not in the water.)

cheers,
Simon

matt h · 18 June 2006, 21:29

hi there! reference your prop paint not sticking, well there is only one way really, get it shot blasted so that the paint will key in and adhere better, then Aly etching primer,2 -3 coats than cellulose or two pack paint,(e;g paint and hardner,) that would probally cost all in 40 quid, might be worth just keep touching it up or get a new prop!!

Poly · 18 June 2006, 21:41

is it necessary to paint/recoat it? mine has also had some minor abuse which i have straightened out but the paint is damaged. (There are also a few scratches on the skeg). Also kept out of the water - so I am figuring any corrosion will be pretty slow? (in the water 6hrs / week absolute max) and I am likely to notice it (I always check the prop to see if I have collected any new dings!)

jyasaki · 20 June 2006, 19:57

Paint wears off aluminum props (sorry, I'm on the west side of the pond) pretty easily. No big deal, as long as the motor's zincs are OK (and not an issue there unless the boat is kept in the water.)

AFAIK, all paint does is make it look pretty so you're more apt to pull out the checkbook to buy the boat.

jky

Searider · 20 June 2006, 20:08

Unless it stays in the water all the time don't worry.

Even if it stays in the water all the time as long as the anodes are good don't worry.

matt h · 21 June 2006, 17:03

try, international paints its called Trilux Prop-o-Drev, says for props,outdrives aluminium and stainless, in black or grey, most places will have some or can get hold of some, comes in a spray can,