Yamaha 30hp, rough idle and engine cuts out

[croangler]

Hello,

I got a small problem with my Yamaha 30hp 2 stroke 84model.

The engine starts fine, 2-3 pulls cold start and he is on. When it warms up, it starts first go. However, I find it that the engine idles a bit rough and sometimes turns off when on idle. And now I find that when I accelerate, it goes top speed for about a minute and then it cuts out and turns off. Then I find that I need to pull the chord 4-5 times to get it started again.
I have a feeling that it is a fuel problem.

I replaced the spark plugs and got a new fuel hose, as the other one was cracking.

With the rough idle I don’t really know what the problem is.
It could be timing, carby…etc

But with the cutting out of motor when it is running flat out, I think it is some fuel problem.
Ill take it for a service and be safe.

What do you think the problem could be? And where do you think is a good place to service it? Any advice would be great.

Regards

Croangler

[Blackened]

G'day

Whats your location? Regards the fuel lines, have you checked/cleaned all lines, bulbs and filters form the tank and to the carb?

Other than that with it cutting out or is it dying @ idle? If dying, more than likely a tuning issue or fuel starvation... If its cutting out, it'll more likely be electrical

Dave

[croangler]

Hello Dave,

I live in Mansfield,

All the fuel lines seem fine but I will give them and the filter a clean.

Regarding the idle, it seems that it just dies, but it does not happen all the time. However, the idle seems rough, I don’t know how an older 2 stroke should idle but this one seems a bit rough.

Regards

[Juzo]

your not using ethanol blend fuel are you? If you are STOP, and put some premium through. I experienced similar probs due to the dreaded ethanol.
Sounds like your Carby might need a clean out, the Premium fuel is good for that. I also had probs using shit fuel line connectors, make sure your using genuine parts, made a difference for me. The cut out at top speed sounds strange, does it sounf like your running out of fuel? If not, like blackend said, could be electrical prob

Juzo

[Blackened]

G'day

If it's due for a service, then get them to have a look at it.

I'll reccomend Anthony from MArine Worx at Capalaba.

0422 330 846 is where you can find him

Dave

[croangler]

thanks guys,

i use normal unleded but i will give premium unleased a go. like blackened said, i need a service.

[Blackened]

G'day

Double check what unleaded you're using, as some has an ethanol blend, and you cannot be sure unless you read the fine print on some of them

Dave