Fuel problems?

[FjordsOfNorway]

Hello Yamaha forum
When I look at my outboard it says Mariner 30M – 689-314142 – O on it. I believe this is a Yamaha made Mariner outboard? I did some searching and I found that it perhaps belongs to 30 M 689-030686 - 689-033487 which makes it a rather old make of 1988 I think.

Anyhow, I got some issues with this engine now and I can barely idle forward with it before it wants to die out. It seems it is not getting enough fuel. When i rew it up going forwards it just dies down on anything more than just above idle. I can rew it up to a high rpm in neutral, but once it is in forward and have some resistance it just dosnt want to do any hard work. Im thinking its maybe the fuel, could that be right?

Do any of you know what could be wrong? Im not very handy with engines or mechanics in general. I am thinking I maybe need to change or clean the fuelpump or get a pro mechanic to look at it. Boat mecanics are almost impossible to get hold of this time of year, anything I could try myself to at least rule out easy issues? The summers in Norway are very short, so any help or advice would be greatly appreciated.

[greasyshaft]

Check the basics.
Compression.
Spark plugs tell a story.
Fuel supply to engine.
Sparking on all cylinders/running on all cylinders?
Throttles opening/advance linkages etc.
Check the fuel filter/strainer on the engine for debris, this filter only catches the big bits so is basically useless.
Fuel system is likely the problem, unless you have a restriction prior to the engine it's carbs off and fuel pumps apart also check the condition of the reeds if you end up taking the carbs off. Try priming when engine is dieing this may give signs of a bad fuel pump, remember the fuel pump can also leak fuel into the crank case causing a rich condition.
Buy a service manual for your engine, maybe mariner wrote one that isn't a cluster **** like the yammy ones
Check the basics first though it is an old engine.

[grf00]

If it where a car, do the simple. However these two stroke oil gas mix motors have very small jets (usually just two..an idle and a high speed) Small screw in plugs in bottom of carburetors that have small holes in them..the idle one is smaller then a sewing needle) Just a few bowls of dried up oil/gas mixture will stop them up. The idle one is usually hidden behind a rubber plug since it gets it's fuel from a port in the high speed side. Probably your only problem. Carbs need taken off, fuel bowl taken off, jets removed and cleaned. Probably a two hour job. Look up the carb on the fish on line at Yamaha parts.

[FjordsOfNorway]

Thank you so much for the replies. Guys, it was the fuel line! That old crappy fuel line!! I bought a new one and it runs like butter now!! We just got that thing re-loaded with beer cases and are back in action!! Thank you so much for the advices, luckily we didnt have to start messing with fuel pumps, carberators or stuff that we have no clue about. Love you all, happy boating!

[grf00]

Usually, you can tell it's the fuel line if you cannot get the pump ball to go hard. Of course, if the float needles are leaking from trash, it will not go hard also. Glad you go it fixed.