"You did not give us much deta
"You did not give us much detail, but I assume you have a 5.7 I/O with thru-prop exhaust, and that otherwise it runs fine. It sounds like you have the boat out of water winterizing it? You need to make sure you have adequate water supply to the drive leg impeller pump.
At low engine RPM, almost all the water and exhaust exit thru two openings at the lower corners of the drive unit adjacent to the transom. You will hardly notice anything coming out thru the prop. The exhaust vapors will look steamy. The water coming out should be warm to the touch, but not scalding. Your water supply to the muffs on the drive leg should be adequate to cause some leakage around the muff edges while the engine is idling. This assures the pump is picking up sufficient water.
Also make sure your heat exchanger (if FWC equipped) and your exhaust manifolds do not become overly hot while you are warming it up.
The oil will look black in a drain pan. How many hours since last change? I usually change oil every 50 hours or so, and it will be very dark, but not tar black.
Rod"
