Having a few TROUBLES

[Donza]

G'day.

The ol'man purchased a new Yamaha CV30 under 3 years ago. He doesn't get out that often but when he does everything seems to turn pear shaped. Just wondering if anyone had any problems or if anyone can help us out with some more info on this motor.

Here's the background:

He purchased the motor from a pretty big dealer in country Vic. and was told when he bought it that it would be fine to troll with. We try to get up to Dartmouth at least once a year so being able to troll is a must. We followed all instructions from the dealer in regards to running it in (first two tanks at 25:1 then 80:1), kept up with all the services etc. Last July we headed up to Dartmouth (the first 5Lt of oil still hadn't been used) and on the first day we noticed that the motor was running pretty rough. On the second the bottom plug fouled. We changed it and it ran fine for about 1/2 a day. Then it fouled again. On the third day we'd had enough and headed back to the ramp. The motor got to within 9kms of home before breaking down completely. After a 3km row in near freezing conditions two top blokes towed us in. They had a bit to say in regards to the ratio.

We took the motor back to the dealer and he told us that the motor was fine, there was nothing wrong with it, it was only because we were trolling (which he now informed us we shouldn't be doing with this motor). He then told us we should be using a 50:1 ratio. They also put in some hotter plugs. Even after all this the motor still runs pretty rough with a destinked flat spot when accelerating and there is a lag of about 2-5 secs when switching the motor off. There is also alot of black soot coming from the exhaust.

When up and really going the motor runs reasonably well but every now and then you can feel the motor slow slightly then take off again like a cylinder is struggling a bit.

If you can help us out that would be great.

Cheers

Donny

[Noelm]

I guess it all comes down to the fact that a "mix your own" delivers max oil all the time, so at idle (trolling) you will foul plugs a bit, best off to give the Motor a bit of a run every 15 to 20 mins to clean out any built up Oil, or buy an electric/small Motor for trolling.

[Chimo]

What Noelm said but what about buying another fuel tank and hose and mix a trolling brew and a fast running brew and use each for its intended purpose?
Cheaper than another motor I reckon.

Dont forget to label them so you dont stuff the motor at high speed.

Cheers
Chimo

[Noelm]

might work OK, you could run some really good (read expensive) Oil at a very low ratio I guess, would solve the problem kind of, but you would need to be wary and alert to swapping back for a high speed run.

[winston]

Donza, this is exactly the reason I changed from a CV 30 to a 30D (3 cyl) after 6 months. The CV 30 is a piece of cap when it comes to trolling, I woul troll or idle for less than 5 min. and the plugs would foul. This really pissed me off because I had a CV 40 for 6 years and it was a fantastic motor. It would troll all day then take off without fouling the plugs. The 30 D is a far superior motor. The CV 30 should still be run at 100:1 and then perhaps a shortburst a full throttle every 10 min. This may help but unfortunately the only real solution is to change motors. Cheers Winston.