Outboard Is Not Accelerating

[fisherman22]

I have got an outboard suzuki 15 HP 1994 Model, I never had a problem with it.

However, yesterday while i was fishing the engine was running properly on forward gear then all of sudden it stopped accelerating.
Regardless if I put the gear in forward or reverse it runs in very low speed with full fuel on.

by the way, when i put more fuel power the impeller injects water with a high pressure as it usual does but the boat runs in very very low speed (same speed as the idle speed), The temperature of the injected water from the impeller and the outboard are normal.

I appreciate any help or advise.

[MarkJ]

Check that the throttle linkage hasn't worn through.

You can test by ripping the cover off and moving the throttle at the side of the carb by hand. If it revs up normally then think it may be the linkage.

[Chief Engineer]

Ethanol Based fuel....rebuild carburetor

If the engine revs up....it is either a shear pin or spun hub

[ozskipper]

Party broken shear pin?

[GordMay]

Greetings and welcome aboard the CF, fisherman22.

[ReMetau]

Sounds like it may need a new prop or prop hub.

[Vasco]

Either the carb is gummed up or you've spun a prop. If the water behind you boils up but you don't move, it's the prop. If the engine will not rev up it's the carb.

[thinwater]

All good possibilities.

Also check the fuel filter. I small slug of water can blind it very suddenly, typically when a few waves shake the tank.

A complete carb rebuild is not always required; drop the bowl and spray out the gunk, with special attention to the needle valve and bottom. Only takes a few minutes and has a 50% chance of success.

Not a shear pin. At that horsepower the prop will have a rubber hub. These can be rebuilt ($36 at http://www.soderbloom.com/proprepair.html). In this case, the engine will rev but the prop is turning slowly when under load.

Note: when asking for help, a clear description of the behavior is very important.

[fisherman22]

Wow!!, thank you all for the quick reponse.
I checked the prop, it seems the prop hub needs a replacement.

does anyone know where can i found a replacement of it in Sydney? or is it better to buy a new prop?

thank you again, this is really a great website to share and solve marine problems.

[thinwater]

Originally Posted by fisherman22

Wow!!, thank you all for the quick reponse.
I checked the prop, it seems the prop hub needs a replacement.

does anyone know where can i found a replacement of it in Sydney? or is it better to buy a new prop?

thank you again, this is really a great website to share and solve marine problems.

Nah, just have the hub replaced. Google "propeller repair Australia marine" and you'll see a ton of shops. They must press it in.

Another option is to buy a new prop (~$120) and rebuild the old one as a spare; they're not hard to change on the water.

[ATC]

How old is the gasoline?

[Cheechako]

Is the engine revving up? If so id say the prop hub is shot. If not, could be main bearings.. Had that happen with a 94 yamaha.

[fisherman22]

Originally Posted by Cheechako

Is the engine revving up? If so id say the prop hub is shot. If not, could be main bearings.. Had that happen with a 94 yamaha.

what do you mean by "main bearings"?
thank you

[Cheechako]

crankshaft bearings. Does it vibrate or resonate maybe a little?. hopefully that's not it. An ex outboard mechanic I met in Trini helped me fix it... it was fast with him doing it. The bearings were ball bearing assemblies.

[Cheechako]

Originally Posted by thinwater

Nah, just have the hub replaced. Google "propeller repair Australia marine" and you'll see a ton of shops. They must press it in.

Another option is to buy a new prop (~$120) and rebuild the old one as a spare; they're not hard to change on the water.

Wow... a new prop for that is $120?? Check ebay! Last one I bought was about $25, unused...