Originally Posted by Neil Smart.
I have got a Thundercat with a Yamaha 2001 50hp. I ran it last week and it was fine no problems what so ever. However went out today and started fine ticked over fine let it warm up for about 5 mins. Went to give you about half throttle and the engine didn't like at all. A little bit of White smoke as no power and the engine itself looked like it wanted to rip off the boat. It was shaking like mad.
I used semi-synthetic two stoke oil last week with no problem. This week I used a cheap two Stoke oil. Would this has an effect??? Or is it the spark plugs???
Should I change the plugs after every outing and what's the best oil to use.
Thanks in advance.
Are you using marine 2 stroke oil? You shouldn't be using the oil you get for chainsaws etc as the engines run at different temperatures to outboards. Look for a TWC-3 oil grade. If your uncertain redline outboards are local to you, they'll sort you out with the right stuff.
Doubt its the plugs, you shouldn't have to change the plugs after every outing, with an engine running nicely and under normal use changing them annually should be enough.
White smoke generally = steam, which could be a result of overheating from lack of lubrication.
Is the engine Pre-mix or injected?