Tohatsu M25A2 propeller !!!!!!!!!!

[phillnjack2]

Hello folks
my friend has a Tohatsu M25A2 with serial number 21881.
we know this old girl is ancient (76 to 83) but it realy is a good reliable engine now we have coils replaced with
a couple from a evinrude.
The engine performs as good as new and is pretty good for a 25hp.
The prop on the engine is definitely too small as the revs just go straight to maximum and above with 2 people in
a avon s400 inflatable sportsboat.
The prop on there at the moment just has 2 letters to identify it, these being A&E.
We are not exactly sure of the pitch but from measuring the prop its a 9 inch diameter. and around 9.5 inch pitch.

The boat is mainly used with just 1 person and we are going to try and find something like a 12 inch pitch for this.
But we just cannot find any props on the fleabay or elsewhere .

The prop is the old type of shear pin prop with the pin staying on the shaft and the prop sliding on then cone/nut
with split pin etc. ( photo to show the old prop )



Does anyone know what other props apart from tohatsu or nissan will fit the engine i.e omc,honda,mercury etc.
once we know what make of prop can be used we can then go onto finding a suitable size for the boat /engine combo.

i know this is a tall order, but someone somewhere must of tried different makes of props to fit these old engines.
we do know the johnson 9.9 definitely dont fit ha ha we tried one already.
so if anyone knows what other props can fit the slpine/shaft then please let us know and we can go and try one out

cheers

phill

 

[Sea Rider]

Re: Tohatsu M25A2 propeller !!!!!!!!!!

You should know firstly what's max rpm achieved at wot installing an induction tach, then go from there to select a + pitch for rpm to go down if assuming that you're over reving. Usually portable engines used with inflatables that are light must be pitch corrected, they produce near full stated max factory parameters at wot and in some cases with just the driver alone will definitely be over reving.

Being that horse so old, mission impossible to find a original Tohatsu prop, check Iboats props, probably could find a Solas non thru hub prop for that engine.

Happy Boating