Question for the boaters

[Jessie]

I have a 2006 90hp Merc on an 18' aluminum bass tracker.
I want to put a stainless prop on it that will be good for a quick plane but also as low of an rpm cruise that I can get.
What would be a blade pitch that would work best?
They're expensive and I want to get it right.
Thanks for any help!

 

[Rudi]

Ask your Merc dealer.

 

[yaktamer]

Knuckleball.

 

[Jessie]

Swing and a miss

 

[d524ax]

A couple of our local prop shops will work with you until you get what you want out of it. You might ask some in your area. Good luck.

 

[dockmurgw]

Just my opinion, so take it for what its worth...for that size outboard and that style boat, add a planing fin to the outboard.

 

[doublesharp]

2 stroke or 4 stroke? A 2 stroke will turn a bigger pitch than a 4. I'd say 19 for a 2 stroke and 15 or 17 for a 4. You need a prop shop or at least spend some time on tin boat forum.

TinBoats.net - Forum

 

[Jessie]

It really doesn't need a planing fin. It planes off pretty quick.
It's a 4 stroke.
I've searched the web and I'll get on the phone with a dealer. Where I bought it is closed. I was hoping someone here was running a similar setup for fishing/cruising and share what works for them.

 

[Imissedagain]

Get in touch with a shop that knows how to ... prop out a boat.
Depth of the prop shaft, "type of engine mount" and other factors influence what size/pitch prop will give you what you need.

You might have a friendly shop that will advise, have parts and let you do the work/testing.

Frank and Jimmies might have some experience with that boat but your dealer should know.

Catch 'em up!

https://www.fjprop.com/

 

[Jessie]

Thanks all! I'll be cruising the few shops around and see what I can glean.

 

[doublesharp]

Does yours look anything like this? 2006 Tracker All-Fish w/90 Merc 2 stroke. I don't remember what pitch the prop was but it was right. Run low 40s and cruise great 35mph. I hit a big lick on it when I sold it but it is one of the few things that I have a little seller's remorse over. That evo hull design is just right.

I'm running a 16'5' w/50hp Suzuki 4 stroke these days and it's a dandy. I'm mostly in deeper, weed free water these days and am satisfied with an aluminum prop. I'm on the Ohio River a lot and there is so much submerged junk in the water that I'd rather tear an ear off an alum prop than wreck a lower unit. Used to spend much time on Lake Okeechobee and you couldn't run that swamp w/out ss prop - too many weeds. SS prop was like a mower blade.

Gone but not forgotten


today's ride

 

[Aggie1906]

Conflicting requirements. Lotta pitch for quick start. Less pitch for top end speed. Gee, boaters should know that. Get some qualified advice.
Then, maybe it's just me. Lotsa water around here.

 

[PatriotX]

I found this expen$ive stainless prop in the river a couple of days ago…laying right next to a very large rock…

If you're in rocky areas, aluminum is more forgiving on the lower unit.

 

[Imissedagain]

There's the three vs four blade conundrum as well.

In four decades of boat work lotsa fast boats to play with.
Helped some younger co-workers setup a Donzi Sweet 16 with 450HP.
Brother was in from the Sierras and we were out on a sailboat when the Donzi pulled up.
My brother jumps in the back seat and I yell... hold on tight.....
as they nail the throttle and prop walk down the ICW and out the inlet.
They brought him back later that day.

 

[S&W629]

I spent ten years in the recreational boating business...

Stainless Steel Props are the stiffest/strongest....and the least forgiving of all props available. As others pointed out...if you strike something hard...the SS prop will transmit the shock to the gear set/drive train. Very expensive to repair. Aluminum is more forgiving....cheaper to replace than..to replace/repair drive train.

As for acceleration/speed...its always a compromise. Ideally..you match your prop pitch to prevent over revving the engine(redling the tachometer) But changing the load( people )..will affect how your engine/prop combination will perform.... I often recommended a Propulse Composite prop...that the user could with an allen wrench change the pitch.(up and down)..for the load it would push on a given day....and if you did break one...you can replace the blade ..not the entire prop....never had one returned....

 

[444 Magnum]

I bought a SS prop after I replaired/replaced three aluminum props. Was never a problem, but I wasn't in rocky areas either. On my 18' fiberglass bass boat with a 120 hp outboard, I went with a 17 degree to get the best balance of hole shot and top end. With that setup, I got up quick enough to ski behind and ran about 55 on smooth water-plenty fast enough for me.

 

[67tempest]

Call Mercury, they will ask you all the specifics of the boat and what your intended use is and then recommend a prop. The last pontoon we had came with a prop that was awful. Poor acceleration, poor top end, cavitated terribly on turns, just not fun to drive. I called Merc and the prop they recommended was a night and day difference. I highly recommend calling them before you buy anything.

An aluminum prop is a lot more forgiving than stainless in the event you hit something. The prop will absorb the impact and hopefully prevent any damage to your lower unit. It's a lot cheaper to replace a prop than a lower unit. We always ran aluminum and went through quite a few of them over the years, the lake we are on is pretty shallow in spots. The new boat came with a 250 Merc and a stainless prop. We bought a spare and it was close to 4 times the price of the same spec prop in aluminum.

 

[Jessie]

Conflicting requirements. Lotta pitch for quick start. Less pitch for top end speed. Gee, boaters should know that. Get some qualified advice.
Then, maybe it's just me. Lotsa water around here.

Yes they conflict and that's the reason I'm asking. I'm looking for a general purpose prop that can squeeze the most out of both ends of performance.
Gee..

 

[WR Moore]

My boat is under a thick coat of dust, but one prop isn't gonna do it all. At least not without adjustment like the adjustable Propulse unit mentioned above. The prop that came on it didn't have enough pitch and I kept hitting the rev limiter. Got one step higher pitch and hit a good spot. Out of simple curiousity, I picked up a composite 4 blade "rescue prop" and installed it to see how it did. Slightly smaller diameter, don't recall the pitch but got a better hole shot and it didn't seem to make much difference in top speed.

The totally composite props are pretty cheap, but they're horsepower/weight limited. The OP situation would be fine and they do make a great get you back to the marina item.

 

[Nevada Ed]

You need to figurue in the elevation that you are at.........

the gross weight of boat and people..........

also how the weight of stuff inside the boat is placed, to help get up to speed.

Your motor dealer shouls be able to help you out and let you test at least two..................
before buying one of them, if a good dealeship.

Some times the book data can be off by one pitch number per a boats setup.

For a slow troll you might need to get a troll plate.
Good luck.