2004 115 4 stroke prop/hole power issue

[cobra 81]

I have a 2004 115 4 stroke on a 2004 sea pro 1900sv center console fiberglass boat. Last year I changed the original aluminum(3-y 6E5 17K) beat up prop. I did alot of research and got a stainless cabelas 13 1/4" 17P 3 blade prop. Same specs as original alum prop I guess. It doesnt perform well. It almost impossible to get out of the hole now. If there is any weight in the back, I cant. With a full 54g fuel tank and 2 guys, 1 guy has to go sit at the bow to get on plain. Any info is much appreciated.
I took another look at the old prop and there looks to be alot more blade surface on the old one. I am starting to think this is why the new cabelas prop isnt performing. I am looking at a SS 3 blade yamaha prop on ebay and it looks to have more blad surface than the cabelas one I have. Should I get the yamaha oem prop? Sell the cabelas?

[boats.net]

You usually have to drop one pitch size when going from alum to SS prop.

[cobra 81]

so I should go to a 16 pitch? every person or place has told me a 17 or 19 pitch. you dont think it has anything to do with the blade surface area?

[99yam40]

Sounds like you may have motor problems if you cannot turn the prop to proper RPM.

Performance Bulletin Home most 115 on this site show a 17-19

A Yamaha dealer/shop can put a test prop on and run a test to see if motor is putting out like it should

[cobra 81]

so I ran it today and the rpms top out at 4900. Im starting to think maybe it it just the prop???

[kanco1969]

Prop size

So which prop did you finally purchase for your 115?

I have a 2003 F115 and I am having a heck of time getting on plane specially when fully loaded with 4 guys and dive gear.

Any feedback would be appreciated.

I currently have a 13x19 alum prop on my 18 foot wellcraft CC boat.

[LeadSinker]

As, for comparisons if this helps, I'm running a 13x19 solas 4 bladed SS on an 18' Hydra Sports with a 115 2 stroke Yamaha, with 4 people and lots of fishing gear and coolers 30 gals fuel, I, can get up on plane fairly easy and still run 5100 rpm's, and I'm currently battling an intake air leak, my 3 blade alum 13x19 will run 5500rpm's easy, but dont know if thats because its 2 stroke and they tend to be better on the low end, or just flatter hull design, but last year my timing slipped back to 20 degrees from full advanced of 25 and my power went way down, something to check out

[rodbolt17]

you need to drop at least two prop sizes, 4900 is about 1000 RPM low for an F115.
that motor needs to be propped to spin 5800-6000 RPM with THAT days load.

on the two stroke timing issue, it simply cannot slip.

[LeadSinker]

Was not trying to mislead anyone, maybe "slipped back" was the improper Terminology, sorry, What I, meant to say was the stop adjustment screw had adjusted itself over time off of the proper setting causing some power loss