water heater connections 1999 5.7

bman440440

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My buddy wants me to help him install a water heater... I need to know where to connect the water lines to the engine... its a 1999 mercruiser 5.7 alpha
 

QBhoy

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Above is spot on. I just winterised a friends same set up. Need to remember and blow water out the coil when winterising. Many forget !
 

Tassie 1

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That has inspired me to get off my backside and fit my aftermarket hws too,

can l ask for a link to that info?
not in my merc manual and the instructions from the hws seem overly complicated
 

bman440440

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Above is spot on. I just winterised a friends same set up. Need to remember and blow water out the coil when winterising. Many forget !

thanks! no winterising here in So Cal... it only gets down to a bone chilling (for us) 45 degrees :joyous:
 

QBhoy

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thanks! no winterising here in So Cal... it only gets down to a bone chilling (for us) 45 degrees :joyous:

You’re making me sad, haha. Been pretty mild here in Scotland so far and not been below freezing yet. Currently getting a pretty wild, wet and windy storm though. Into double figures and mild. Boat out the water and first signs of winter depression showing already ! Thankfully have the wee Yamaha 2 stroke jet ski to see me through the winter blues. Works a treat.
 

Tassie 1

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I can read it now
do l still need to install the flash thingee for other relevant links there?

(not the sharpest tool in the shed when it comes to computer blackmajiercky,
honesty is the best policy l find lol )
 

alldodge

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Sorry bman440440 if we're getting too far off your topic

do l still need to install the flash thingee for other relevant links there?

No
 
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bman440440

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Sorry bman440440 if we're getting too far off your topic



No

no prob... but now I have another question... I found a mercruiser water heater install kit "805984A1" for the engine and I'm trying to figure out what the size of the connectors are... at 47+ tx that seems steep so I would like to go to my local marine supply (and no they don't carry that part # I checked first) and pick up the connectors without going to my buddy's boat first and pulling the block off plugs to bring in... any of you Iboats guru's know what size they are?? THANKS so much for the help!!
 

bman440440

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https://www.mercruiserparts.com/805984a1-heater-kit-water

Think they should be 3/8 NPT. I would suggest going to the local hardware and take them with. The ones in the link show a gasket so they can get closer.

On my Formula the factory used the port side block drain plug to connect the hose going to the WH.

I also found where there supposed to be connected to... according to the instructions with that kit... see pic's I have attached
intake.jpgwpump.jpg
 
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