1801 RE-Propping INFO

[josephprior]

I have a 2015 1801 with a 2015 f115XB that came with the black painted Yamaha K-19 Prop. The boat has never been quick out of the hole but once I added a trolling motor to the bow and Two 80lb batteries to the the console the hole shot really went to crap so definitely time to re-prop. I contacted Ken at prop gods and took his suggestion. I wanted to post all the info I can as every time I tried to search for some I found very little available for the 1801.
WOT per Yamaha is 5300-6300
fuel tank 51.13 gallons
NO T-top
NO trim tabs

#'s with K-19 prop
Normal running 29mph 4600 rpm 5mpg
39 mph at 5500 rpm. 1 person full gas all fishing gear
41 mph at 5600rpm. 1 person 32g gas all fishing gear
40.5 mph at 5600 2 people and full gas
40 mph at 5500 2 people 1/2 tank all fishing fully loaded.
hole shot ? did not time it but should have as was slow.

Replaced with POWERTECH-SCD3 part # SCD3R16PYM90
1 person all fishing gear and 20gallons of gas
4600 27mph 5mpg
4800 29mph 4.8 mpg
Normal running 4900 30mph 4.7 mpg
6200rpm 40mph 3.6 mpg
hole shot about 3 sec

I have yet to get the numbers with a full tank and an extra person. I wanted to do the light numbers first to make sure it was not under propped. This is as light as I will ever run it as I usually fill up after I have burned 30gallons. I did trim up to see 6300rpm at one point but front ended was bouncing at that point so trimmed back down and I would never run that way. I also ran with live well filled(I have the large one under the fiberglass flip flop rear seat and the #'s are the same but hole shot was about 1/2 sec more. I can say the hole shot is less then half of what it was and it almost fells like someone is pulling the carpet from under your feet. I should have done this a few years ago as I was at the low end of the wot RPM range since new but never messed with it as I was in the RPM range. When I list the "Normal Running" this is where I feel the engine sounds the best or at ease if you will. I did loose .3 mpg with the higher 300rpm but the speed is still almost exactly the same. I will see what I get with another 30 gallons of fuel but from previous #'s only slight differences in fuel burn and rpm's are noticeable. I do like the way it steers and docks at idle speeds with full fuel better then a light tank but that is another thing..

Kind of a long post but wanted to put this out there for others. Ken at prop gods was great to work with by the way.
-JOE

 

[GoodChance]

Great post. Very detailed.

After looking through your numbers, I almost wonder if 17" might be a bit better since it appears that you are hitting the rev limiter of the engine

And you are right ..... Ken is great to deal with

 

[philspat]

Did you ever get new numbers loaded? Wonder if i could go with a 17 cause i wont be running as heavy as you.

 

[Clarkbateman]

In my experiences, find the prop that runs motor at 6200-6300 rpm wot with your average load and that’s the right one.

 

[tomc585]

I think you might be under proped with that 16p. I would have expected it to have 17p as OEM. I found the 19p a little bit too steep for the low rpm trq of the 115's.
I swap them a lot and it always seems to work best with the 17p for all around fun.