Propping a F70 - 17 foot tiller

[The_owl]

I recently purchased a used aluminum tiller boat with a yammie F70. The boat is a G3 Angler V172.

The prop on it is in need of repair and/or replacement. I plan on using it primarily on Lake Sakakwea so I’m leaning towards a SS prop with an alloy prop for a back up.

The prop on it now is a 12 pitch with a 13.875 diameter prop. Previous owner states that he got 28 mph top end with excellent hole shot. I have no idea where he was at in terms of RPM’s.

I have a couple of spare props in my garage and I’m wondering if either would work on this boat; both are Solas 15 pitch SS in 14.5 diameter. One is a three blade and the other a 4 blade prop. Does anyone have an educated guess on if either of these props could perform on this boat? Or is the diameter too big to even try?

If I have to buy a prop or two, I’d prefer to run Mercury props as the dealer that’s closest for me sells them, also I’ve good luck with them in the past.

Does anyone have any advise?


Thanks

[scrotcaster]

Call prop works in bismarck, they will know

[rapala_09]

Call prop works in bismarck, they will know

Good luck getting through.... They closed some time ago I believe.

[scrotcaster]

Bummer,, that sucks.

[Captain Ahab]

I think SS props for rigs that size offer little benefit for the extra money. I’d say get another AL prop a pitch or two higher for light loads. I’d say topped out at 28 is the rev limit if the hole shot is really good. I’d probably go with the same prop in a 14P.

[Kngkong]

i have an f70 on my tiller, its an old fiberglass lund nisswa so probably a bit heavier. I'll check what prop i have on when i get home tonight and let you know. I get 28 mph and pretty good hole shot

[Nods]

Running a f70 on a 1781 Yarcraft tiller. Not sure on diameter but it is an aluminum Yamaha prop in a 14 pitch. I can run 30 up river and 35 down at 6000 rpm’s.

[Kngkong]

I'm running a 12 pitch with mine. might need to try a 13 or 14 and see if i can get some more speed?

[Allen]

I have a feeling your hole shot would really suffer if you go up 2 inches in pitch and 5/8 of an inch in diameter. You should lose 150-200 RPMs for each inch increase in pitch, and I'd guess you'd also lose another 150 RPMs because of diameter. Will it push the boat? Sure, but that's an awful lot of change for similarly raked and cupped props. At the same time though, if it doesn't cost any $$ to try it, you really have nothing to lose by trying.

[eyexer]

And you’ll loose more rpm going from aluminum to stainless.