replace Mercruiser 2.5L 1989 with Mercruiser 3.0 1994

liusigou

Chief Petty Officer
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May 11, 2015
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545
Today I bought a Mercruiser 3.0 1994. All cylinders pressure are higher than 145. I will remove old 2.5L and mount 3.0, then connect 3.0 to the old wires.is it easy? But I have found there are different between 3.0 and 2.5.

Can anyone help me to upgrade?
 

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Bondo

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But I have found there are different between 3.0 and 2.5.
Ayuh,..... Such as,..??

The long blocks are plug, 'n play,....
Differences in the accessories need to be dealt with,...
 

liusigou

Chief Petty Officer
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545
I do not know where I should connect these two lines
 

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liusigou

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The serial NO. is 0B876780, The year is between 1988 ~1989. But my seller told me the year is 1994
 

Scott06

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Apr 20, 2014
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It seems that both of thme are connected to the water in take? What happen if I just leave the two lines alone? water will leak?
I am assuming your old boat does not have power steering and the new engine does?

the 8-10" long metal tube in the water intake hose is a powers teering cooler, this cools the PS fluid on the return line. Leave the cooler in the water inlet hose, remove the PS pump and 1/2" or so diameter hoses as you wont need them without PS

if you are swapping the complete engine it will be bolt in. just take the PS off if you dont need it
 
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