2000 model 60hp warning buzzer???

[gaffer1972]

Im getting a warning horn and rpm decrease when pulling a tube and also get a warning horn when *****ing at low rpms. I take off the cowling for a bit and it acts fine. I have changed the impeller and seem to have good flow. Any ideas as to what I could do to remedy this????

[gaffer1972]

maybe i should add this engine is on a 2000 model carolina skiff and its gauges doesnt have any temp lights or oil lights. I mix the gas and oil in the tank so no oil injection.