2004 Mainship 400 speeds and RPM with single Yanmar 370hp.
Mainship 400 owners, Would you share your Single Yan 370 hp, speeds and at what RPM (ang GPH if you know) with me.
My boat seems to be 1-1.5 knots slower what is found on the Stella Blue and original mainship site as far as the speed and RPM tables.
Like they show 2000 rpm getting 8.3 knots. My boat at 2000 rpm I am lucky to get 7 knots. I've got to get to 2500 to hit 8 knots and they show 9.5kts
Also before you ask, I have:
New Bottom, shaft, coupler, PSS shaft seal, Cutlass bearing, even new Trim tabs.
Prop removed and balanced.
Prop speed on shaft and prop.
Rudder dropped etc.
The bottom is as close to factory new as it can be.
The Yanmar runs fine up to WOT and will hit 12.9 knots with tabs down but no where near the 16.7 knots that is shown in the tables.
I would appreciate knowing if others see the same as I do or do I have something else I need to look at.
2004 Mainship 400
Clear Lake Shores, TX