new closed cooling system question

[DB Durako]

Hello out there. I used to visit here under a different handle quite often. New boat, new handle, new questions.<br /><br />My Merc service manual (#31) for my new rig says I have the air actuated single point drain on my Closed Cooling system. The manual says to pull three blue plugs and pump air into the system, then see if it drains.<br /><br />I got more than a quart of water out of the system following the book and it all came out of the drain on the water distribution housing which is the lowest part of the system, port side of the motor. My question----is this the normal amount of water to drain from this type of system?<br />Nothing much drained out of the starboard side seawater pump assembly---just a trickle of water there.<br /><br />I know my block is protected, but I don't want to crack anything on the raw water intake side of the system. Any tips from anyone who has drained this type of system would be appreciated.

 

[jaybirdtx]

Re: new closed cooling system question

As long as the poppet valve indicator stayed extended it should be fine. I have noticed though with these engines that you have to keep pumping into the air inlet while draining to keep the indicator extended. They also have BLUE drain plugs to open just in case the system doesn't drain. If you don't feel comfortable with the amount drained using the air valve drain it manually with these plugs.

 

[rodbolt]

Re: new closed cooling system question

I persoonaly dont trust the air purging, it even has a disclaimer in the operating manual. thats why I always manually drain the system and refill with a non-toxic AF mixture.<br /> never know when we will get that abnormal 3 days with highs in the single digits.

 

[Don S]

Re: new closed cooling system question

First of all, the manual does not TELL you what you have. It tells you the possible options you have, and how to deal with each. If you have the air actuated single point drain, then you don't have to worry about any blue plugs..... they are on the manual drain system.<br />As far as using them, I agree with rodbolt. I have a few of the 5.0's and 5.7 MPI's with Freshwater cooling out there in boats that is impossible to get to any manual drains, or even the raw water pump short of pulling the engine. I just pull the intake hose off the transom shield or the water pickup thruhull and suck antifreeze out of a special bucket designed for the purpose of deploying antifeeze mixture in this way. <br />Here is a picture of this highly specialized piece of equipment. You have to figure out the method to use to collect the AF and water coming out of the drive. Those plastic kiddy pools work great for a catchment system (Remove kids and pets first).<br /><br />

 

[rodbolt]

Re: new closed cooling system question

hahahaah glad I aint the only one with that bucket, I also have the one from west marine and one with a 300GPH bilge pump in it. thats why I use the non toxic stuff, dont have to worry so much about catching it. at willoby bay we had a 100 gallon wood box on wheels with a rule 1500 pump that we could place under the back of the boat and do everything while running it on the AF mix. just had to use the refractometer occasionally to check the mix dilution so we could add makeup concentrate.<br /> remove the kids and pets?? man I knew there was something I forgot, ill just tell them its a jaccuzzi

 

[Don S]

Re: new closed cooling system question

remove the kids and pets??

If ya don't they start complainin' when you fog the engine ....... the antifreeze doesn't seem to bother them much.

 

[DB Durako]

Re: new closed cooling system question

Thanks for the responses. Don---I know I need to be careful with words but the manual definitely states that this system is standard with the Horizon B3. It is in the chart which shows engine types and standard cooling systems.<br /><br />I did not want to refill the water intake part of the system since the manual specifically says to leave it empty with the green indicators extended.<br /><br />However, before draining the intake side of this system, I did get the engine up to temperature and ran three gallons of the pink -50 stuff from Comeco throug the intake on the drive using a bucket similar to the one in the drawing.<br /><br />If what Rodbolt says is right, I could have just left that pink stuff in there and not drained the system at all. Correct?