Port engine overheating?

[Tri-sheild]

Went down to the boat last weekend to winterize. All went well. While warming the engines to change the oil and such I noticed the exhaust from the port motor was steeaming. I felt the manifolds on both engines to find the starboard was cool and gage read about 160ish. The port engine felt hot but gage read around 150ish. The starboard has new impellar and housing spring 2010, port ?? Impellar is my first thought. I was told that the circulating pump could be at fault. Any thoughts?

 

[SCORPIO]

How hot were your risers? Is this a raw water cooled engine? You may have a clogged riser passage thus not letting enough water thru to cool the exhaust. Its getting too hot and causing the steam. How old are the risers/manifolds?

 

[Tri-sheild]

Raw watercooled. Both manifolds on the port were hot. Easily over 200, I didn't leave my hand on it very long. But in contrast I could rest my hands on the sb manifolds indefinately. I did rev the engine to 2k and the temp on the gage started coming down. One problem is, I think the temp sensor is way off. Obviously. In the spring I will put a new raw water pump on it. I don't know how old it is. The SB got a new one in April.

I was told this boat spent its life on Lake Lanier in GA. Now on Bull Shoals in AR. Always a freshwater boat so I dont envision a clogged riser. Both are hot, not just one, also.

The individual who sold me the boat said possibly the circulation pump. As a 30+ yr GM tech, I have never seen one fail to circulate. Leak yes.

I thought I would put it out there for anyone who might have, or the reason for it. Barring the failure of the impellar/raw pump

 

[jaxon5000]

Sounds like you need a new impeller on the port. If there is NO water coming out of the exaust and it is steaming, either your impeller is bad or on of your cooling hoses is either not connected correctly or is completely off.

I just replaced both impellers on mine and they were brand new. The first because the clamp broke on the cooling hose and burned it up, the second because the hose was not on all the way.

 

[pdelac]

samething is happening to my boat changed impeller no overheat just slight steam, manifolds 190deg on port engine 120 sb 145deg at gauge and blocks with non contact temp meter going to remove manifolds suspect need acid dipped manifold drain plugs clogged hand drilled got grit then water

 

[MMLAM]

First thing I would do is check the condition of the intake holes on the lower unit. It could be possible that you have blockage covering up the intake holes.