North Australian FISH FINDER TM forums

I have a 25hp Yamaha 2 stroke on my small boat and have looked after and serviced it well for the last two years. It has run like a dream with absolutely no prblems startingnor running. It unfortunately sat for three months and now won't run. It turns over easily with a little choke and then runs a few seconds but it won't hold idle.
So far I have ,
Removed carby and cleaned but not stripped down,
New plugs
New fuel filter
New fuel,

I'm now thinking its gummed up in the needle and seat.

Any thoughts on a remedy

Tropical

Have you taken the bowl off the carby? sometimes it can stick due to the fuel drying out or like you said the needle has stuck to the seat or sort of stuck.......If you can get it running give it some revs and block the carby intake with you hand to starve it of air this sometimes will dislodge something stuck in/under the needle........You could get really rough and squirt some de-greaser down it's throat while running this used to make my old 40 tohatsu cough and splutter but cleared it up.

Tropical your gunna have to get the carby stripped bro, unleaded fuel has this brown varnish like shyt in it that would have blocked your main jet and nothing dissolves it get a carby kit ,and put thru it, get a exploded view picky sit down at the kitchen table take your time and do it

When you pull the jet out soak it in coke. It eats the varnish and shines the jet right up.

If not a air gun and blow the shitt out.

Fairdinkum coops coke !!

wally gator wrote:Fairdinkum coops coke !!

Get a coin that is tarnished and drop it into coke and see what it does. It will shine it up after about 10 minutes. Just ensure you rinse it off with fuel or simular as it will become tacky once dry.

Google "generator blocked jets" or something like that. I found it on there and it worked a treat when I did it.

That because it contains phosphoric acid - better to use rust off or Ali brite- has more acid in it and less sugar - works about 50 times faster too

OK carby is off. Just need the time to sit down and pull it apart. Any carby champions out there want a cash job over Xmas....

One hour later carby back on prime, the bowls, first slow pull to get the fuel flowing, it fires and ran like a charm. I did note however all the jets needles and float were so clean it looked new. Must have been the slightest bit of cr.p that made it stick.

Now I think I turned the air fuel mixture screw in either one too many or one not enough turns. It runs well but I'm sure it isn't the factory setting.....

Anyway the little beast is a goer again.....

The before shot

Good out come. The idle screw should be easy to get to to and if it is over reving turn it down half a turn if under reving up half a turn.