What paint would be the best to use for an aluminium prop ?

For your Mercury prop?

No not the Mercury as it’s a stainless one, but for my auxiliary Suzuki 6hp, talking of the Merc, still got issues with it cutting out from tickover into gear !!! Tickover set at 950+ rpm Starting to annoy me now as carbs have been sonic cleaned and are like new, my technicians reckon it’s the lower crank seal ??? Beats me

Waterproof ! Sorry .... Kgarla !

welshhealey wrote:talking of the Merc, still got issues with it cutting out from tickover into gear !!! Tickover set at 950+ rpm Starting to annoy me now as carbs have been sonic cleaned and are like new, my technicians reckon it’s the lower crank seal ??? Beats me

This is a classic problem, (assuming this is your 80hp on the winner) most common fix is to richen the mixture a bit on the needles give them each a 1/4 turn anticlockwise. If it still does it give them another 1/4. My boat has a foot throttle which is a good cheat, give it a little blip, let it die back down then into gear and open up a shade.

As for paint, anything you like, it's an auxiliary so ideally will never be used and just needs static corrosion protection.

Cheers Floater, I’m so glad to learn that I’m not the only one to have problems with the said issues on a Mercury, ( yes it’s the 80hp on the Winner ) so will do as you suggested and will keep you posted. With regards to the paint for the prop on auxiliary, will nip down to Halfords get a suitable colour and crack on with that soon, was just unsure that normal acrylic ( waterproof Kgarla ) would bond to aluminium ,as you say being an auxiliary it won’t get used much hopefully! ( unless the 80hp Merc has a bad day ! )

It has always been difficult to paint aluminium, it just doesn't key very well for paint. Zinc chromate is the preferred primer but I think like many other chemicals it's now banned for domestic use. We used to slap it around liberally when I worked in MoD aerospace, called it yellow peril and was essential coating between riveted or bolted aluminium components.
As I said earlier any paint will suit your application, acrylic, cellulose, Hammerite, but not emulsion

If the merc keeps giving you trouble post again on the engines thread. Fastjeff, Alacrity, Se7en are all merc officianados.

To see if your lower crank seal is leaking pull the bottom spark plug out. If there's water droplets on it or if it's super clean in relation to the others then it may be leaking but it's not the only cause of those symptoms So not a conclusive test for a leaking lower crank sealjust a possible indicator. If the plug is as grubby as the others, happy days the seal is good.

I use this supplier. https://www.ebay.co.uk/itm/VHT-LIGHT-YE ... SwRLZUEvd5

On aluminum I prime with a U-Pol etch primer,

Hi Floater, yes , it’s the lower crank seal, bottom plug is clean as a whistle compared to the other 3 just thought I’d let you know on here as it’s easier, any more posts on this as you say will be put in the engine room .