Re: Hard Starts When Warm
Once I get it started there is some of smoke, but there has always been smoke when I start the engine. Probably more than other boats especially the newer ones. I have just figured it was just being an older engine. After starting the smoke goes away and runs GREAT. I hope this helps.
Some smoke at startup is normal. Too much smoke can indicate a carb problem or oil injection system problem.
I had a similar starting problems with my 1996 150HP. I had a lot of smoke at startup that went away after the motor ran for 10-20 seconds and then the motor ran fine. I assumed that it was not a carb problem since it ran fine otherwise. It turned out that my oil injection system was being over-pressurized due to a faulty check valve. This caused excess oil to be pushed backwards into the fuel line after shut down resulting in a too oily gas mix in the cylinders at next startup. The gas/oil mix does not ignite as well if it is too oily. I replaced the check valve and my problems went away. Your results may vary. If you pre-mix, of course, this will not apply to you.
When talking to a mechanic at my local Merc shop about my starting problems, he gave me the advice to make sure that the motor is tilted up/forward a little before turning off the engine. I'm not sure if this was so that any excess fuel will run out the front of the carbs instead of towards the engine or if the float valves just work better with the motor trimed up a little, but it seemed to help. Again, your results may vary.
Good luck and let us know if you solve your problem and what solved it.
