In the salt, all the numbers change!

[jergofish]

I got my new 215 with 175 Suzuki about three weeks ago. My wife and I quickly put on the necessary 20 hours for an engine check in fresh water in the Sacramento/San Joaquin Delta. Since then I've towed the boat down to Mexico and have been running in the Sea of Cortez. All the performance numbers change dramaticly. Here's some examples

Prop WOT rpms in fresh water 5900, salt water 5400

Gallons per hour at 3500, fresh water 4.9, salt water 5.4.

I haven't had a flat stretch of water to run a complete set of numbers but WOW, salt is some heavy water!

Do not know what the problem is. But this is fact! Salt water is more BOYANT than fresh water. Great salt lake everyone floats fresh water they sink.
The boat rides Slightly higher, should run easier, in same conditions.waves chop ect. Against the current would not change rpm. Speed yes. Your straining for some reason. Loss of rpm's + increased gas use proves that. check for something draging if nothing. Try a scale.

[jergofish]

Rockman, you know, you're right about the water but it's also heavier and I thought it might affect my prop in that its heavier to push around.

Then again, when I ran the numbers in fresh water I was on empty and nothing in the live well.

Down here I'm running with 65 gallons of gas and a live well full of water, lets see, that should add another 600 pounds. Maybe THAT's why I'm going a little slower!

[jergofish]

I pulled the boat out to fuel it today. It's been the salt for nine days, you would not believe the marine growth (we're talking about an eighth inch of slime!) in nine days in the tropics. Wow, is there any doubt that I'm going to put on a coat of bottom paint before berthing the boat when I return home!

Maybe that's another reason why the numbers are falling!