What is causing this ?

[Tom465]

Hi,
I have a Yamaha 30 DEO

At the moment I can only drive 1/4 throttle before this happen...

Yamaha 30 DEO - YouTube

Checked fuel tank pick up
All fuel lines
Fuel filter

Thinking it could be do with the carbs ?

Any information on fixing would be greatly appreciated ! Thanks

[Boats&Outboards]

Doesn't sound like carbs to me. have you done a compression check ? That's where I'd start first. Does it do it on muffs too ?

Peter @ Boatsandoutboards4sale ~ askboatsandoutboards4sale@sky.com ~ 07930 421007

[PeterM]

My first impression is electrical . I think fuel problems give you more of an overall powerloss than a misfire ( which that sounds like) - based on my own experiences of petrol problems .

Easy quick steps are new plugs , then HT leads ....after that you are into a bit more than I'd care to guess at .

[Jizm]

Do you have a tacho?

[Tom465]

No, have not done a compression test or tried with the muffs.
Doesn't have a tacho

It started last time I went out. It was fine for the whole day then when I came to start it up to go back home it would happen just before WOT. 3/4 throttle would be fine.

Went out today and now it have become worse. Can only go 1/4 throttle before it happens.

[Boats&Outboards]

Are you sure it's getting an oil supply & pumping water adequately ?

Peter @ Boatsandoutboards4sale ~ askboatsandoutboards4sale@sky.com ~ 07930 421007

[Tom465]

Yes, just topped it up with oil and it had a new impeller last month

[Jizm]

Have a look at this video of my yam 50 taken a couple of years ago.

http://www.youtube.com/watch?v=F6Wsn...e_gdata_player

[Tom465]

hmmm, yeah that sounds very similar, how did you fix it ?

[Jizm]

Originally Posted by Tom465

hmmm, yeah that sounds very similar, how did you fix it ?

It was electrical if I remember. Checked and sorted all connections. New plugs etc.

[matt h]

its definatly electrical. as above say, change plugs and retest check plug caps to HT leads to individual coils to stator coils etc, take flywheel off and check clearances of the pick up etc

[Jizm]

It may even be the rev limiter for get you home mode. In case of low oil or overheat.

[Davie]

Disconnect the pink wire going into the cdi unit.

[Tom465]

For mine it turned out to be low oil. My oil tank had about 1/3 left in it which is enough for about 5 more trips out for me and looked fine.

Turned out when I was cruising along the engine was level and then when I went WOT the boat rises up and would think that I had low oil. It would lower the limiter and would then decrease the lower the oil is.

Jizm made a comment about the "get you home mode" so I thought id just fill up the tank to see if it made a difference. Went out and she was fine !

Note to self, have more than 1/3 oil in the tank Big thanks to Jizm or I would still be trying to fignure out what it could be....

[Jizm]

No worries, think mine was a dodgy temp probe in the end.