Yamaha two-stroke 8 hp problems

Questions & Answers
1

Ahoy! I am struggling to get my (2003?) Yamaha 2 stroke 8 horsepower outboard engine to work. I winterized it last fall, and drained the fuel from the engine, carburetor, etc. I added StaBil to the fuel tank.

When I tried Monday, it started, ran for about 20 seconds, and then stalled. It has not started again.

Since then, I have tried a fresh tank of fuel, I took apart/inspected, and reassembled the carburetor, and today I added new spark plugs. Still nothing, not even a cough.

I am admittedly not a motor head. In fact, I would describe myself as largely incapable. But I am determined to change that and start by getting this outboard to behave. I welcome any suggestions and I thank you in advance.

Here is a picture of one of the old spark plugs.

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2

I think you missed a step. If it was “took apart, cleaned, assembled…” the result may have been different. Outboard carburetors have a way of gumming up over the winter and cleaning them completely can be a challenge. Usually soaking for a while in a good carb cleaner and then applying compressed air does the trick.

3

Good evening and thank you for the response. I cleaned it as best I could without using carburetor cleaner. I visualized the pins and jets and the holes all seem clean.

Side note, taking these things apart and putting them back together is a form of mechanical microsurgery!

4

This may be a bad coil these 2 stroke engines will start when cold but as soon as the coil heats up it dies . This has happened to me before.

Brian Cayer

5

Thank you for the response. It seems like if the coil heating up was the problem, it would start/heat up/stall every try, no?

6

No not really . This is a problem that almost caused me to give up. But the new coil fixed it after all .

7

Thanks. New coils seem to vary in expense up to $125. Ow!

8

Richard

To me it sounds like it’s not getting fuel. So I would check the in line filter and replace. Also make sure the fuel flows easily from the tank to the motor using the primer bulb.

9

First, hold the plug by the rubber wire (don’t touc the metal with your finger, it hurtslike the devil. Hold the sparking end to metal on the engine and pull the cord/turn the key. If no spark, probably the coil. If there is spark, you have a fuel problem.

Go to EBAY and look up parts for the model engine you have. Look up ignition coil. It will probably look something like this: https://share.google/ujD2gCYYHkAzXA1rH

Chuck Garbarino.

10

Thank you for the response. I agree it sounds like it is a problem with the fuel getting into the cylinders. The bulb squeezes and fuel flows to the carburetor. I know this since when I took the carb apart it was full of dinosaur juice!

11

You said it ran for twenty seconds or so. That was perhaps the carburetor emptying. But did it refill? A stuck float valve or blocked filter would stop fuel flow.

12

Have you tried running it on “Starter fluid” ?