winterizing woes

Nov 25, 2013
9
Catalina 32mk11 Chesapeake Bay
Having a problem running anti-freeze through my yanmar 3gm30. When I pull the intake hose to put it into the bucket, the system gets air bound and will not draw. I have the same problem when I clean the raw water strainer, where I go through a series of bleeding off air from the impeller housing and the anti-syphon valve. Is there an easier way?
 

CCHer

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Jul 7, 2010
230
Beneteau 37 Cranes Creek, VA
I used to do it by pulling the hose and sticking it in the bucket. a real PIA as you infer from your troubles with that. A Yanmar mechanic showed me the light...a why didn't I think of that moment...close the intake seacock, open the top of the strainer, have mate start the engine while I pour the pink stuff (propylene glycol only, never ethyl glycol) into the strainer while my first mate looks for good color coming out of the exhaust. Takes about three minutes start to finish and no mess.
 
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richk

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Jan 24, 2007
488
Marlow-Hunter 37 Deep Creek off the Magothy River off ChesBay
On previous boat (H35) with the 3GM30F I put a valve in above the seacock for the raw water intake. In one position it worked normally; i.e. fed raw water to the engine. In the other it drew antifreeze from a gallon container of it (of course when the sea cock was closed and the valve to the bucket was open.) No more woes taking hose off the sea cock. I just bought a clear plastic tube to run antifreeze through so it was a bit easier to see when it was drawing air. (Needed someone positioned to turn off the engine then.) I also recall it only took 1 gal to winterize the 3GM30F.
 

Scott

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Sep 24, 1997
242
Hunter 31_83-87 Middle River, Md
Agree with CCHer's method. Been doing it that way for a few decades now. Very easy. :dance:
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Try pulling the hoses from the raw water pump and letting them drain. the take a turkey baster and suck the water out of the strainer. Pull the back off the raw water pump to get that to drain and you are done. Air don't freeze and a few little puddles are not going to burst the plumbing. As I count it that is 6 screws/nuts to take off. Not so much of a PITA.
 
Feb 2, 2006
464
Hunter Legend 35 Kingston
I suspect that the original poster maybe has a problem with the water pump not making a good seal, and thus not being able to get properly primed. Maybe broken/missing vanes on the impeller? or some other wear in the housing?

For my 3GM30F, from the outside, I stick a small diameter hose into the thru hull (from the outside) making sure to get a good seal, then put the other end into the jug of anitfreeze that is sitting on the ground. My engine will easily draw up the air in the hose, and then it will slurp up the antifreeze. I then just run the engine until a bucket catching the exhaust water is pure antifreeze (usually 1.0-1.5 gallons).

No tools needed, nothing to loosen, nothing to forget to re-tighten,

I use the same technique for the head and washdown (which share a single intake thru hull.
 
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Mar 3, 2003
710
Hunter 356 Grand Rivers
I put nylon "T"s in the lines above the strainer. I put a valve in the side at the bottom of a 5 gallon bucket and attached clear water hose to the valve. On the end near the T's I have a swivel and fitting that screws into the nylon T. The swivel fitting allows me to screw on the fitting without the hose getting all twisted up. I pour 3 gallons of pink antifreeze in, open the valve and start the engine. After 2/3 drawn down, I stop the engine. I winterize all systems on my H356 in 2 hours. Takes about 20 minutes to do both the Yanmar 3GM30F and the generator. I then do the head and wash down pump and hose. Takes about 15 minutes to drain water system and put 4 gallons through it. Last I do the HVAC. 1:45 to 2:00 hours and I am done, 12 gallons of antifreeze. The secret is the bucket and hose setup and the nylon T's.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
...I put a valve in above the seacock for the raw water intake. In one position it worked normally; i.e. fed raw water to the engine. In the other it drew antifreeze from a gallon container of it (of course when the sea cock was closed and the valve to the bucket was open.) No more woes taking hose off the sea cock.....
Having suffered through the first year's winterizing, I did like Rich did, but with a tee and added one antifreeze valve. A planned added benefit is if your boat takes on water, you can close the thru-hull, open the AF valve and draw the flooding waters out of the boat, through the engine and overbaord- a "free" bilge pump in effect.:dance:
 
Mar 26, 2011
3,401
Corsair F-24 MK I Deale, MD
+1 to adding valves as needed. Why boats come though the factory without proper winterizing fittings (mine was built in Canada) is beyond me. You will save time, glycol, and leaks. I will be done right, every time. If you have to take anything apart each year, you are doing it wrong.

Some prefer to drain and blow things out. OK, but still add the fittings!
 

womble

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Jan 13, 2015
41
Catalina 30 Middle River
Having suffered through the first year's winterizing, I did like Rich did, but with a tee and added one antifreeze valve. A planned added benefit is if your boat takes on water, you can close the thru-hull, open the AF valve and draw the flooding waters out of the boat, through the engine and overbaord- a "free" bilge pump in effect.:dance:
Please could you tell me the name/type of valve you used?
 
Feb 27, 2004
172
Hunter 335 North East, MD
I use a product called sea flush which is basically a funnel which fits in your sea strainer into which you invert an open jug on winterizing fluid. It's a bit pricey but it's "boat stuff" but works well for me- easy peasey www.seaflush.com/reviews/
 

NYSail

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Jan 6, 2006
3,048
Beneteau 423 Mt. Sinai, NY
I have always just removed the hose from the thru hull and stick it in bucket. I like to flush the system with fresh water for a few minutes before adding the anti freeze so I run a hose to the bucket and fill, then before I start the engine I open the strainer and make sure it's primed, tighten things up and run her for 15 / 30 minutes..... then when I am ready wait till the bucket is almost empty and start pouring anti freeze.... hope it works that way and that easy with the new engine.
 
Sep 25, 2008
957
Macgregor & Island Packet VENTURE 25 & IP-38 NORTH EAST, MD
That's alot hanging on those thru hull threads.:yikes: And I don't see any wooden plugs close bye. Could be a candidate for MainSail's hall of fail.;)
 
May 17, 2004
5,031
Beneteau Oceanis 37 Havre de Grace
Yes, but to be more precise, never ethylene glycol, but also, never ethyl alcohol based anti-freeze, which a lot of the pink stuff is. Search for propylene glycol stuff with no ethyl alcohol.
https://marinehowto.com/freshwater-system-winterizing/
If doing this on the hard, then yes absolutely PG only. If in the water however the marine toxicity of EG is no worse than PG, and EG is much better for rubber components like impellers. In any case you're right not to use ethyl alcohol.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
EG is poisonous to humans. If winterizing your potable water system, use PG! Easier to use just one product, and, as far as I know, PG is less expensive than EG.
 
May 17, 2004
5,031
Beneteau Oceanis 37 Havre de Grace
EG is poisonous to humans. If winterizing your potable water system, use PG! Easier to use just one product, and, as far as I know, PG is less expensive than EG.
Yes, very poisonous. Just to be clear I was talking just about the engine, not the potable system. And to be honest I confused this thread with the other one with the guy who wants to use his boat over the winter and therefore probably doesn't want to pull the impeller to protect it from any harmful effects of PG.