2005 342 ,, 5.7 with XDP outdrives , I want to change my water intakes to thru hull

rick12

2005 342 with XDP out drives , 5.7 engines , I want to change to thru hull water intakes . Two reasons , 1. I run in shall water often and the XDP water pick up is in the front of the unit, I tend to take in silt into my heat exchangers. 2. I want to remove the water hose by the bellows to give more room for the bellows , I already have a 1 inch intake for the gen, I could tee it and run a hose from there around the engine to the power steering cooler on the port engine. I would want another 1 inch thru hull with strainer to power steering cooler on starboard engine . Then remove the water  hose from the lower unit to transom shield .
 So can this be done ? will it work ? where to drill thru hull for second pick up ?
thanks rick

Liberty44140

My mercruiser 5.7s with bravo 3 has both and both are used. I believe that even if you have a thru hull water pickup you still want water  coming in through the drives to help cool them. My thru hull intakes are on the bottom on both sides just in front of the drain plug. That way the valves in the bilge are just in front of the drain plug and fairly easy to access. 

rick12

my thought was with the water hose off water would still be pushed thru the outdrive and dump out by bellows to some degree? but both is a thought , but I still will get silt . thanks

Liberty44140

I don't think it will pass through exhaust bellows until it's passed through your heat exchanger and risers. Next weekend I can take pics of where my valves and intakes are for you to see. The intake hoses come to a Y to join with the intake hose off of the drive and then it passes through a strainer and then in to the water pump. So you'd need to y them together and add strainers if you don't have them. Maybe strainers will help with the silt? 

rick12

That would be great , thanks ,,,
My water on the XDP pick up is on the very front of outdrive , goes thru outdrive to a 1 inch I.D. hose from top of drive to  transom shield { this hose I want to remove } .Then short hose from inside of shield to power steer cooler . I have no strainers .

Liberty44140

Interesting, I wonder if strainers would be a way easier fix 

Liberty44140

Here are pics of my thru hull pickup valves in the bilge and my port engine strainer. 

rick12

Thanks very much , great pics, The way I see it that's your port engine? The hose comes out of the  Y runs under engine to the strainer by the gen , from the strainer to the front of engine water pump?  Thanks again ,  great help

Liberty44140

Yes - the pic of the strainer is the port engine. Pic is looking aft. The strainer for the stbd engine is between the engine and the batteries.

Regarding the below pic, circle 1 is the Y for the port engine. You can barely see the red hose at the top is water in from the port drive. The hose with the green stripe is water in from the thru hull to the Y. Then the black hose runs down, under the engine and to the port engine strainer that is next to the generator as you assumed. Goes from the strainer to the port engine water pump. Circle 2 is the port engine thru hull valve, Circle 3 is the stbd engine thru hull valve. Stbd engine is the same, the thru hull and the drive hoses Y together near the batteries. The thru hull hose again goes under the engine, to the Y and then to the stbd strainer. Strainer direct to water pump. 

If you are really going to execute this I can get more pics but keep in mind that you still will have water coming from your drive, I dont think you can or should stop that due to drive cooling but I may be wrong.