2002 vs 2014 DF140

[sisuman]

Just replaced my 02 DF140 (the corrosion problem) with a 2014 DF140 and suffering a 5mph performance hit thru all rpms. Same prop, same transom height position, same length.
Has there been any change to engine location that would affect distance of prop leading edge from transom at the waterline. Have gear ratio changed that affect prop speed?

[Moonlighter]

Suzuki changed the gear ratio of those 140's in about 2007. It was 2.38 now it is 2.59.

That would explain the difference between your 2002 model and a new one.

Comparing the old 2.38 gear ratio, it would seem that the new gear ratio calculates at 9% slower prop speed. Looking at a typical 14 x 20 SS prop commonly used on that engine, it would appear that one should add 2" in pitch (which is 10% more pitch), so a 14 x 20 on an old engine should have roughly equal performance as 14 x 22 on the new gear ratio.

So you might need to change props.

Google and you will be able to confirm this. I am assuming that they didn't change the gearbox ratio on the new 140A, so the above should remain true.

[sisuman]

Moonlighter you were right on

Thank you for the gearbox and prop info. I did verify the DF140gearbox chg in 2007. I changed the prop from a 17 pitch to 19 and performance was back to normal with the new 2014 engine. Disappointed that the dealer blew off my question from the beginning and claimed that there was no chg. Thankfully we have this forum with great interaction... Thank you once again