Zinc trim tabs and stainless steel props

[DrumInlet_NC]

I was doing some online shopping for zinc trim tabs for my Alpha one when I saw a warning that they may not work with stainless steel props. My existing tab and the anodic bolt heads are eaten down to a nub so I?m thinking there might be something to this. Can any shed any light on this?

 

[Bondo]

Re: Zinc trim tabs and stainless steel props

I was doing some online shopping for zinc trim tabs for my Alpha one when I saw a warning that they may not work with stainless steel props.

Ayuh,... I'm under the impression that refers to the fact that Many of them have a Physical Interference problem...
They Hit when rotating,.... Atleast once anyways...

If your anodes are burnin' up, You have a wiring problem, or a shorepower problem...

 

[Bt Doctur]

Re: Zinc trim tabs and stainless steel props

Or too much stainless steel in the water.The zincs are doing exactly what they were designed for, to be eaten away saving your aluminum drive housing.I was changing mine twice a year.

 

[DrumInlet_NC]

Re: Zinc trim tabs and stainless steel props

Nope, no shore power, no adjacent boats ? whatever is eating them up, I?m generating it. The trim tabs I?m looking at with the warning are 2 ? inch standard tabs ? didn?t think a prop strike would be a consideration. I?ve seen a couple of places that recommended using aluminum ? any thoughts on that?

 

[Bt Doctur]

Re: Zinc trim tabs and stainless steel props

You want a less nobel metal protecting it,
What corrodes away first: Stainless Steel
Aluminum
zinc

 

[bruceb58]

Re: Zinc trim tabs and stainless steel props

All the latest Mercruiser anodes for saltwater are an aluminum alloy.

 

[DrumInlet_NC]

Re: Zinc trim tabs and stainless steel props

Yea, I saw those ? but using anything other than zinc just doesn?t seem right...

 

[bruceb58]

Re: Zinc trim tabs and stainless steel props

In theory zinc is less noble than an aluminum alloy but the reality is that often, the zinc anodes can develop an oxidation that renders them useless.

 

[DrumInlet_NC]

Re: Zinc trim tabs and stainless steel props

Thanks guys ? I?m just going to keep my SS prop and go with the zinc. I?ll replace them as often as I have to.