How many blue plugs in this 5.7.

RandyBC

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I tried twice updating an older thread but got no response. Can anybody tell me from the pic below how many blue plugs are holding back seawater (if any) ? I've found 4 different plugs including one on the bottom left block, two manifold, and one on the front bottom right. Given that I drained the coolant when I pulled the plugs I think that aside from the intake and outake hoses, the heat exchanger would be the only other place for raw water.

Also, my merc's s/n: 0M070881. Can I confirm that this is a 2001 engine?





Merc.jpg
 

Bt Doctur

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Aug 29, 2004
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Re: How many blue plugs in this 5.7.

seawater should only be in the heat exchanger and risers.
 

RandyBC

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Re: How many blue plugs in this 5.7.

So flushing the sterndrive intake with 5 gal of pink antifreeze would be adequate for winter storage with respect to protecting against freeze damage?
 

BoatDrinksQ5

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Feb 11, 2012
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Re: How many blue plugs in this 5.7.

flushing and then draining ...yes.

(Not sure with your setup) Generally you will want to let it run on a hose for 10-15minutes first to ensure the thermostat is open and maintaining operating temperature (temp stops rising and sitting at 160/140) - otherwise the pink won't make it into the block fully.

or if stat is just cracked it will mostly go directly back out the exhaust. Right? Resulting in very little pink making it completely through block?
 

RandyBC

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Re: How many blue plugs in this 5.7.

With the closed cooling system, there should be no water in the block, only antifreeze n'est pas? Therefore, running until the thermostat opens shouldn't matter with this particular setup. That is my understanding, please correct me if it is not correct.
 

Bt Doctur

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Re: How many blue plugs in this 5.7.

remove the drain plug on the raw water side of the heat exchanger and drain it, remove the 2 brass plugs from the risers and drain them.
 

Fun Times

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Re: How many blue plugs in this 5.7.

Can anybody tell me from the pic below how many blue plugs are holding back seawater (if any) ? I've found 4 different plugs including one on the bottom left block, two manifold, and one on the front bottom right.
Also, my merc's s/n: 0M070881. Can I confirm that this is a 2001 engine?
You may have a blue plug on the tube, see item number 39 & 40

http://www.mercruiserparts.com/Show...nbr=2697&bnbr=120&bdesc=Closed+Cooling+System

Yes, this engine serial number is a 2001. Manufacture Date: 03/01/2001

With the closed cooling system, there should be no water in the block, only antifreeze n'est pas? Therefore, running until the thermostat opens shouldn't matter with this particular setup. That is my understanding,
You are correct.
 

RandyBC

Seaman
Joined
Jul 31, 2012
Messages
66
Re: How many blue plugs in this 5.7.

I didn't find one on the tube. Thanks for the link and the other input.
 
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