slow acc./slow speed

First day in the water after the winter, but the boat will not accellerate like normal, and it will only hit 4000 rpm.

I have tried something like this before (in another boat) after about 15 min it was okay and I think it was water in the gasoline...

This time it is not okay after 15 min...I have made a compression test and all cylinders are ok. New plugs have been fitted and I made spent 2 liters of carburator alcohol in the gasoline.

There have been about 30 litres of gasoline in the tank during the winter, but I have filled the rest with new gasoline.

I can reach full RPMs when the boat dont sail, but there is no power when I start to sail.

What could be the next to check??

Water/dirt in the carburator ?
Water/dirt in the fuel filters ?

Fuel pump membran damaged ?

(my boat is a CC 1996, no fuel injection)

Best regards,

Jens Chr. Nielsen
Copenhagen

I think that I have found the problem in the carburator. The secondary throttle plates are not activated because the secondary vacuum device was not tight enough to the carburator house, that means loose in vacuum.

I have not tested it yet, can anybody tell me about the secondady throttle device ??(it must give a bad accelleration and top speed if it is not working ??!!)

jens chr nielsen