Pontoon Boat & Deck Boat Forum

Just before end of season last year I managed to mangle the prop on our boat.
Im in the market to buy a new prop and will probably go back with stainless.
Currently I'm running a 16 x 14 aluminum (115 hp command thrust).suntracker 22dlx
If I go with stainless will i need to go back with same size in stainless ?
Anyway I've was told because of flex in the aluminum prop a smaller stainless would be need for same performance .

Top end is nothing to even talk about (25-27 light load)but I can easily lift two skiers or two tubes with grandkids on them and I don't want to lose that

I used to run performance boats, so I know a little bit about stainless props. First up... If you are at risk of mangling your prop, stick to Aluminum, cheaper to replace and a lot cheaper then a leg!

The biggest difference in Aluminum vs SS props (other then strength) has to do with blade geometry, for your application there should be not enough deformation to account for a change in pitch (due to blade flex). So the short answer is stick to the same spec prop you have, I doubt you will see much difference...

The potential issue I see is getting a identical prop, once you go to stainless the blade geometry can change dramatically, they can be thinner, double cupping etc. this can change your rpm... trial and error or checking with someone who has the same set up is helpful, it is not a exact science !!

Thanks for the good info,I went thru the prop scenario a few years back on my ranger boat and luckily had a great dealer with a large selection of used props and some good mechanics that helped me .

I don't want to do that again,so I think the wisest for me is go back with exactly what I have because It works good for my use

Kytim wrote: ↑

Sat Jan 30, 2021 8:45 pm

Thanks for the good info,I went thru the prop scenario a few years back on my ranger boat and luckily had a great dealer with a large selection of used props and some good mechanics that helped me .

I don't want to do that again,so I think the wisest for me is go back with exactly what I have because It works good for my use

And there’s your answer.

I have a 20ft Lowe with a 90 Merc Optimax. I have a stainless and an aluminum prop. Both 16" pitch-both Merc props. The aluminum prop is 1-2 mph faster than the stainless---still trying to figger that one out.

Lots of submerged stumps in my lake so I run the stainless...I know a good hit will probably tear up my gears if I hit something hard with the SS--but an aluminum would stay dinged up.. Even hitting a stump idling will hurt it while the SS hitting something at idle will usually just kill the engine with no prop damage.