Thru hull water pick up
 

My boat is starving for water. 575 Engine running hot all new pumps, probably due to transom suction hose. Any thoughts pros/cons?

When your engine is running hot what is your water pressure ?

What kind of water do you run in, ie brackish, silt? Do you have a sea or sand strainer? Flush motor periodically?

Something does not sound right , I have my pick-ups mounted on the transom and I have 15 lbs of water pressure to the engines and mine do not run hot at all , you might have a water volume problem .

Did you add the sea strainers? if so do you still have the screens in the bottom of the offshore pickups? I was told if you add sea strainers you should remove the screen/grill on the bottom of the pickup.

You know your water pressure but whats your water flow? Remember water pressure can be had without hardly any water flowing and this would be a potential for overheat condition.

What are oil temps like?

It may be a long shot but I had sand granuals jam up the nylon check balls holding them open in the thermostat housing. Part #9. Take your hoses off both sides and make sure they are not hung open,https://www.mercruiserparts.com/Merc...OMMON/2599.gif

I have removed my thermostat checked those spring loaded balls and yes agree pressure does not equal volume. I am getting plenty of swirl in my strainer. I had even eliminated my strainer by going direct from the sea pump to the transom. Hitting temps of 190. took my outdrive off last night to check transom suction hose as well as the plastic adapter on the inside a slight corrosion build up on the inside but still was able to put my finger in the opening. Cant think of anything else WTF

Are you running a circulating pump? If so, maybe its bad? Also, are you sure the motor is really heating up or is it a bad gauge or sender? Have you tried removing the Tstat all together just to see if your still getting hot?

I had a similar issue with my previous boat with B&M blowers and it turned out the supercharger snout was in need of service and it was getting hot. Being very close to the temp sender, it sent the temp reading up, although it didnt get quite as hot as yours. just a thought

great point now that you mentioned that I did notice a slight winding noise this year seam odd header are cool to the touch as well as the block ill check it out thanks for imput

Are your headers getting discolored?

I struggled with water pressure issues on my old 575 Fountain, this causing higher operating temps at 90+ mph. I ended up plugging a couple of holes in the lower (DWP), and that helped - but never really got it to where I wanted water pressure.

Have you checked water hose that runs through the transom? Those are known to corrode and close up the hole. Mine was ok. I replaced inlet hoses, sea pumps, removed coolers for flushing, etc. My next step was a water pickup on the transom, but sold boat before that happened.

Terry