1996 SUZUKI 40 HP. MOTOR HAS A HARD TIME TAKING IN WATER TO COOL IT

[MidCoast]

On a 1996 Suzuki Motor, 2 stroke 40 hp, the motor has a hard time taking in water to cool it on cold starts. This usually only happens immediately after the boat comes off the trailer and we are about to head out. So pretty much on cold starts only. Motor seems to only take in water after I put it in gear and the propeller starts spinning. However, on other starts, after that cold start, motor takes in water fine and normally. Can this be a waterpump issue?

[marine_man]

When you say take in water, do you mean that you don't see water coming out the indicator on the rear of the boat until the motor warms up?

Your motor very likely has a thermostat, that only allows water to flow out the tell tale indicator once it opens and the engine is at temperature.

marine_man

[MidCoast]

Yes, I don't see any water coming out of the rear indicator. Another important detail is that while at home, if I attach the water hose to (one of them suction cups with water coming out of it) and cover the water intake area above the propeller of my motor, even on cold starts, the motor has no problems taking in water to cool its engine. My motor seems to only have problems out on the lake.

[marine_man]

Any idea when the water pump impeller was replaced last? What does the stream look like at idle? Strong, or more so dribbling?

In general, you cannot gauge water pump performance when running it on the hose, as the water pump is having water force fed through it instead of having to draw it.

Based on what you said I'd be inclined to replace my water pump impeller this season.

marine_man