Engine revs

[Chasbroon]

I don't have a spec sheet for my 1990 Mariner 100 HP two stroke. Consequently I am not sure of the maximum permissible RPM
when WOT.

It is fitted to a Humber 5.5 Atlantis and one up I reach a maximum speed of 32 MPH with a tachometer reading of 4200 RPM.

I guess the engine should rev out higher than this.

Any advice re this and suggested prop specs etc gratefully received

Phil

[kerlstone]

Hi Phil, im wondering the same thing, i have a 100 hp 4 cyl mariner 2 st, 1989, on a 5.5m bwm rib, inside the engine cover is printed max revs, 4,750---5,250, ive only had this engine for a short time and max speed so far has been 32kts, 2 up, at about 4,200 rpm, it has a stainless 18p prop on it, so im thinking i need to drop the pitch to increase revs, is your engine the same as mine ? and what pitch prop do you have on it ?.

Gerry.

[Chasbroon]

Yep same performance as as me, Gerry.

My RIB is afloat just now, but I will try and see what size and pitch prop I have and get back to you.

Thanks for letting me know the max revs for the engine though.

Phil