Little green air indicators on 350 mag mpi horizon

Trashman

I used the little blue pump attached to the engine to pressurize the system.  For the life of me i cannot get the left indicator ( two green indicators ) to pop up.   Ive hit it with a little wd40 and wiggled it, tapped it ...nothing.   Looks like the two air lines from it go to the raw water pump and the ones on the right go down to the bottom where theres a little orange rubber tube that drains when i pressurize.  I ran the engine to temp on the muffs then fed the engine antifreeze through the strainer, then pressurized and removed the blue plugs.  My first ques is am i ok with what i did or is there water trapped somewhere without that indicator popping up. And Also, I was wondering if this process fills/ winterizes the two heater hoses that run through the hot water heater?

boattech01

you need to make sure the green and white lines going to the sea water pump are connected. there should be 2 blue drain plugs on the sea water pump you can remove to make sure there is no water. if you have a closed cooling system the heater hoses will be filled with antifreeze. if it is not a closed cooling system you will need to blow those lines out. 

Trashman

Ok. So my cooling system is the closed type, so im ok with the heater hoses.  I did trace the lines(green/white) to the sea water pump and did remove the blue plugs.... So im guessing the indicator is not an issue at this point.   The antifreeze I fed into the system through the sea water strainer ( seems i have some kind of dual intake for sea water, hose coming from transom and one from a thru hull fitting) drained out of the sea water pump when i removed the plugs, so i should be good.  Im leaving the blue plugs out and i ordered a new set.  The po really did bare minimum on engine upkeep but did perform regular maintenance. I have all the invoices. Thank you for responding this is a huge help

rasbury

You have the same set up as me Trash.....as I am in Fl, I don't have to worry about it. I am curious however, since you have a closed system and your antifreeze is just going through the risers and the heads, isn't draining the water sufficient? What is the antifreeze protecting at this point in a closed system? During a water pump impeller replacement, the lines on mine being old and brittle, I just capped mine off...I went to the mercruiser place here in Fl., Marine Max in fact, and they had no clue what the lines are so must be a pretty rare set up for Fl.

boattech01

One thing to think about: I leave the blue plugs out after I run antifreeze thru the system and reinstall them in the spring. One of my customers asked me why I do this. I told  him the water and antifreeze have been drained from the block right he said yes, then I ask him whats in the block now he laughed and said air. my comment to him was if air freezes we wont be here to see the crack in the block anyway.