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1985 Mercruiser 350 CID 260 HP Cooling System Winterizing

H

holt

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"Hello Folks: When pouring coo

"Hello Folks: When pouring coolant into the necessary hoses, how do I determine which to pour the coolant into. Looks to be 6 top dead center in the tsat housing area. Can anyone provide a diagram?"
 
"I have always heard it is bet

"I have always heard it is better to run it through the engine with it running to ensure there aren't any air pockets, you would do this by running it through the outdrive with the engine running until it starts to come out the exhaust. I am not an expert though."
 
"Craig:
If your engine is a

"Craig:
If your engine is all raw water cooled, drain the block and manifolds first and pour straight RV/marine -50 or -100 deg.F. antifreeze into each hose. Four hoses are to the exhaust manifolds, one is the raw water inlet (bottom of pump) and the largest is the recirculating pump--pour about one gallon into it from the T'stat connection and 1/2 gallon into the raw water hose. Then pour about two gallons (1/2 gallon each) into the other four hoses. Guy"
 
"Thanks to Troy & Guy.

"Thanks to Troy & Guy.

Question: So, pour into all six, correct? I was concerned that maybe a couple of the hoses were not necessary, in that it would just drain staright out onto the driveway. But, it seems like that pouring into all 6 will ensure all necessary cavities are filled and that if any does indeed drain onto the driveway, that denotes that all is filled and is as should be. Correct?

Is there any kind of schematic, avaiable on line, for the cooling system which shows the water flow from intake to
expulsion?

Last question (for now, while I have everyones attention)- Water exits the engine via the top left and right of the outdrive and exhaust exits through the prop hub - correct?
Thanks Again."
 
"Craig:
#1 - yes--stop pouri

"Craig:
#1 - yes--stop pouring when it starts to run out
#2 - go to this site and you can see a diagram of any cooling system. www.mercruiserparts.com
#3 - if you are talking about the "Y" pipe on a "V" type engine, it exits below the O/D and YES for exhaust.
Guy"
 
"Why not introduce it at the r

"Why not introduce it at the raw water intake and do it right? Not only is it far easier, you won't be looking at huge repair bills next Spring if water collects somewhere.

Hey, the marinas do it that way for a reason. (Actually two reasons: speed and liability.) They must know something!

Jeff"
 
"Question - How do you fog the

"Question - How do you fog the engine and introduce coolant into the engine at the same time? If the fogging kills the engine before enough coolant has been filled - that's not good. If the coolant starts to push out the top of the outdrive before the engine quits, the coolant level might be too low once the engine stalls out.

Starting the engine again to put more coolant in, defeats the fogging. Attempting to fog the engine after the coolant is in, just pushes the coolant out.

Catch 22."
 
"Craig:
Jeff has a good poi

"Craig:
Jeff has a good point based on his years of experience. I gave you a response based on what you requested and since I do it the "thru the hose method". Either way works. But, with the hose method you must drain the water first and then add sufficient quantities of RV/marine antifreeze into each hose to ensure there is not any plain water to freeze.
Guy"
 
"Understood, and thanks. I per

"Understood, and thanks. I performed the "through the hoses method" last year, after having watched over the shoulder of my marine tech for the last 8 seasons. Bought the Sealoc manual last year and everything went A.O.K. Just picking everyone's brain. You can never stop learning!"
 
"It only takes one freeze to c

"It only takes one freeze to crack a block, so if you are in weather that dips below freezing you either must store it somewhere that doesn't freeze or winterize it anytime it has a chance of being frozen. An outboard motor would be a better application in a situation like this, or a closed cooling system type motor."
 
"On fogging the engine...There

"On fogging the engine...There's two schools of thought on how to do this:

1. Spray the fogging stuff into the carb 'til the engine dies, or

2. Pull the coil wire, roll her over, and spray at least 15 seconds worth into the carb.


In method # 1 the engine burns off the fogging oil, doing little good. Not until (or if) it stalls does the cylinders get coated.

I use the # 2 method and have had good results with it. This method is also more convenient.

Jeff"
 
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