Info on late 80's Nissan 2.5?

[Gene Neill]

I got a sweet little Nissan NS 2.5A as part of a boat deal I made. It has seen very little use, looks and runs like it was practically new.

Was this motor made by Tohatsu, or is it a "real" Nissan? The exact year is not known, but it's blue, which I think means '85-'92?

Was this one of those many motors where the only difference between the 2.5 and 3.5 is the carburetor? 'Cause if so, I'd like to get my hands on that carb!

I'd welcome any other info on this motor that anyone may have, and thank you!

 

[pvanv]

All Nissan-labeled outboards were always made by Tohatsu. Year is irrelevant; model/serial is the critical information.
Yes, you can put a 3.5 carb on it, and get a substantial power increase.
The A model has the water pump on the prop shaft, and no shifter. It starts in gear. The later B model has the pump on the driveshaft, and has F-N shifter.
Original shear pins were brass, current pins are mild stainless, which lasts better.
Very early models had points/condenser ignition; those parts are NLA from Tohatsu. Aside from that, parts are available. The motors were designed to be able to run at 100:1 oil mix, but are rated for 50:1 mix; they are almost indestructible.

 

[Sea Rider]

Flush well with fresh water after salt water use, that model has a very narrow peeing tube on powerhead where hose connects to that can clog easily if not well flushed...

Happy Boating

 

[Gene Neill]

All Nissan-labeled outboards were always made by Tohatsu. Year is irrelevant; model/serial is the critical information.
Yes, you can put a 3.5 carb on it, and get a substantial power increase.
The A model has the water pump on the prop shaft, and no shifter. It starts in gear. The later B model has the pump on the driveshaft, and has F-N shifter.
Original shear pins were brass, current pins are mild stainless, which lasts better.
Very early models had points/condenser ignition; those parts are NLA from Tohatsu. Aside from that, parts are available. The motors were designed to be able to run at 100:1 oil mix, but are rated for 50:1 mix; they are almost indestructible.

That is great news! I love this little motor and have big plans for it. It does start in gear, but I can live with that, especially because it starts very well. I have a water pump rebuild kit on order, as well as a spare shear pin and a new fuel cap. I'll have to find a 3.5 carb for it, the extra power will be great to have.

Thanks guys! If anybody has any other juicy tidbits, by all means share 'em!

 

[Gene Neill]

One other thing, Pvanv ... I'm not sure if I have points/condenser ignition or not. I'll have a closer look tomorrow and see if I can figure that out (I'm not a mechanic by any stretch). If I'm not sure, could you tell from pics?

Thanks again!

 

[pvanv]

If there is a CD box in addition to the ignition coil, you have the modern setup (with exciter coil). If it is just a coil, then you have points/condenser. Of course, if you pull the flywheel, it will be immediately evident. Finding points and condenser will be tricky -- maybe a NAPA dealer, if they have an old guy behind the counter, rather than a number-looker-upper. You can order a new carb for a 3.5, but msrp is over $100. If you install a new impeller (there isn't a "kit" available for the A models), and it still doesn't pump well, you may need a pump case and head, as those are not stainless, and the aluminum can wear fast if run in silt.