outboard motor

[lesterl]

On a cool dry day my outboard will run at spec. rpm on a hot humid day I lose several hundred rpm is this normal?

[7outof10]

it is normal for your motor to run a LITTLE bit differrent when it is really humid out but you should NOT be able to see it on the rpms becouse it would be so little lol i think you might have something worng how old and how much hp do you got there ?

[solbes]

I know that my last two outboards have run a little higher RPM's in the cold water in spring. Conceivable that it would run a little lower in the hot summer. Anything over 200 though sounds a little weird.

[lesterl]

I have a mercury 115hp with carberators its 5 years old. I noticed the same thing last year.

[kc0myy]

at the hottest part of the day I went fishing this afternoon (caught a pike and a 17.5" bass). and I could not get over 12MPH with my 14' boat with a 10 horse. I always get 15-16MPH. but I am sure with the hot humid air things were leaning out. I always have the same weight in the boat everytime I go out unless I am fishing with 2 people.

[broken_line]

you mean richening? hot air is less dense so your carb takes more fuel and less air in than it used to..yess i noticed in the cold my boat seems to go 3 to 4 mph faster.. might have to do with the water density and air densiity.. with snowmobiles you loose 20 mph sometimes when its like 50 out and its jetted for -30..

[kc0myy]

you mean richening? quote]

Ah yes sorry my bad I could not remember right