Anti-freeze volume needed for Engine

Status
Not open for further replies.
P

Pete

Perhaps another easy question, but being to new to this size vessel, I'm going to ask it anyway. How much anti-freeze is needed for the raw water winterization. I have a Yanmar 2GM20F diesel engine. As a fresh-water (closed loop anti-freeze coolant) system, in addition to changing the Oil and checking the coolant with a hydrometer, I understand one should disconnect the hose for the raw water intake, immerse it in Anti-freeze and run the engine until it comes out the exhaust. Boat being in the water providing little if any view of the exhaust, I'm interested in how much anti-freeze the system should raw water portion of the system would reasonably take to accomplish a good winterization. I've been told by the marina it's around 5-gallons. Any advice? When starting the engine it immediately starts drawing on the raw water pump no thermostat for the raw water I guess? Thanks in advance.
 
D

Don

Not much

You should be able to find someone at the dock who will watch the exhaust for you while you are inside wrestling with the hose and bucket. That's the only way to be sure,i.e, confirm antifreeze comes out the other end. In my 4JH, I've found that it takes about 4 gallons. More important, the thermostat is closed when cold which means you are not circulating antifreeze through the complete raw water system. You need to get the engine up to op temp first before flushing with antifreeze. Don Illusion
 
Mar 20, 2004
1,746
Hunter 356 and 216 Portland, ME
raw water antifreeze

pete, there is no thermostat on the raw water side, don't worry about that-you should need around 5 gal, have someone watch for your exhaust to turn pink and then keep going for a while. the real issue, after you have pushed af thru the heat exchanger, is the water lift muffler. they typically hold around 2 gal of water, and you want it to be filled with mostly af. remember, the rv antifreeze is not meant to be diluted, so be generous with the AF
 
Dec 3, 2003
544
None None Rochester, NY
On my 33.5...

It takes about 1 gallon of antifreeze before coming out the exhaust. Just did this last week on the hard with same engine and same boat.
 
S

Steve O.

5 gallons??

I winterize the entire boat--freshwater, waste and raw water system--with 5 gallons!! The raw water system should only take 1-2 gallons at most.
 
P

Pete

Thank you

Okay - based on the responses, I'll take it that the 5 gallons I dumped in is certainly sufficient. I appreciate everyone's assistance. I'd love to hear more about winterizing on land. I scrambled to get it done the weekend prior to having it pulled. Thanks again. Pete
 
Status
Not open for further replies.