Nissan 18hp

[Beauporter]

My Nissan 18hp 2 stroke outboard won't run at full throttle unless the choke is all the way out. It runs fine at idle with the choke all the way in, it dies of course at idle with the choke all the way out. Any idea what could cause this problem?

Thanks

 

[TOHATSU GURU]

Re: Nissan 18hp

You have a dirty carburetor.

 

[pvanv]

Re: Nissan 18hp

TG is right on the money. Likely a restriction in the main circuit. Possible also to have some crud in the needle-and-seat. Also may have a slight amount of water in the bowl. Disassemble the carb and soak in good carb cleaner, not just the spray stuff. Then blow out all the passages. A new fuel filter would be a good idea too.

To help avoid this in the future, run only FRESH gas, use a good stabilizer such as K100-MG in the gas religiously, and if at all possible, run a water-separating fuel filter (available at any Tohatsu/Nissan dealer).

The crud in the carb may be due to inadequate prep before storage. Nissan has a good page on their website http://www.nissanmarine.com/tech_talk/winterize.html that describes prep for off-season storage.

 

[Beauporter]

Re: Nissan 18hp

Thank you for the help. I looked inside the carb. while it was running to see if both the flaps were working, both were functioning properly. Like yall are saying must be dirty. Is it very hard to rebuild one of these carbs? Also is there any website that sells carb kits?

Thanks again

 

[Beauporter]

Re: Nissan 18hp

Are there any in depth manuals for 18hp Nissans, this model I believe is a 1990 model.

 

[Wee Hooker]

Re: Nissan 18hp

I have an aftermarket repair manual that covers a range of Nissan 2 strokes that I snagged cheap off Ebay. Pretty decent refference for basic stuff like carb rebuilds. Once off, just disasemble the carb to the level that the kit supports and dump it in a can of carb cleaner (available at any autoparts store.) for a few hours. Then it's dry/blow out and reasemble. Simple really.
BTW: Remember to count and note the turns out on any adjustment screws so you can return everything to it's initial setting. A digital photo here and there while disasembling doesn't hurt either.
Internetoutboards.com should be able to hook you up with a kit.


p.s. Love that 18 hp 2 stroke. Lots of power in a small package.

 

[Beauporter]

Re: Nissan 18hp

I also can't figure out how to identify the exact motor I have. I know its around a 1990 model. I have looked at every spot I can see on the outboard. I did see some numbers stamped on a small plate. The numbers are 80147. Other letters/numbers I found was TH0-00. Thanks for all the help.

 

[TOHATSU GURU]

Re: Nissan 18hp

The model number is the only thing used to determine parts. It will be:

NS18 and then a letter. A, B, C, D, or E.

 

[Beauporter]

Re: Nissan 18hp

Do you know where the vin/ID number would be located? I've looked all over the motor. Would it be under any other parts that are attached?

 

[TOHATSU GURU]

Re: Nissan 18hp

It's on the same tag as the model number. It's on the outside, just below the engine cover.

 

[Beauporter]

Re: Nissan 18hp

Hooray, I found it. I had to scrape paint off that the previous owner put on it. NS18C2

 

[Beauporter]

Re: Nissan 18hp

Thanks for all the help.