Draining engine for winterization

[tmac]

The M25XP Universal maintenance manual states two options for winterization. I quote:  "  To drain sea water system, disconnect hose end at sea water pump that comes from heat
exchanger. Lower free end of hose to a point approximately level with the front engine mount. This will allow the sea water to drain from heat exchanger and hoses.  Loosen the 4 or 6 screws on the sea water pump cover plate. Tap the plate lightly to loosen it, this will allow pump to drain. After pump has drained, apply a light coat of lubrication to protect pump and impeller during storage and replace cover.  Drain exhaust muffler and system separately."
Their second method is of course pumping antifreeze through the system. 
Has anyone (in a very cold climate) attempted the first method?  I'm questioning how thoroughly the raw water system can be drained to prevent damage.

[Jim Hardesty]

Tom,
I've never done the first, dry, method.  If done correctly would prevent freezing.   FWIW I wouldn't take the chance.  Most of us in Erie use the -100 antifreeze, blue or green, in everything except the water tanks believing that it prevents corrosion and prolongs the rubber.  On a different note, a PO added a Schrader valve to blow out the potable water.  I do run thru some pink antifreeze first then I blow it out and leave dry during the winter.  Makes recommissioning much quicker.
IMHO Winterizing the systems doesn't take a lot of time or cost a lot of money, if all is setup well.  I've made up my winterizing kit with a drywall bucket and some pvc plumbing.  It's a half day job at most.  That's engine, water, bilge pumps, head and air conditioner.
Jim

[KWKloeber]

Tom

The M25 and XP are SO SIMPLE to winterize dry.  For the 15 years she was in Buffalo I never put one drop of pink stuff thru the seawater side of my m25 and never had any issue.  The only freeze up I had was on the potable water side (water heater) and that was my stupidity not getting to purging it before buffalo got a cold deep freeze.

The part I like about winterizing dry is that it forces one to open up and look at the things that should be looked at annually.
If you decide you want to do it that method I can guide you the easiest way to do it.

Ken

[tmac]

Thanks, Jim and Ken for your replies.  You both being from the "frozen North", your replies are meaningful to me.
I've winterized my previous boats but those were the Atomic engine and I always did the antifreeze route.  This is my first time with a Universal, and saw the recommendation in the maintenance manual, and it is appealing because I'm not buying and disposing of antifreeze (despite its non-toxic nature).  I would of course remove the impeller and store it as per Ron's suggestions.

Ken - I'd be interested in seeing if your dry method is different than the manual.  I have a small compressor that I'm planning to use on the potable water systems (set at not more than 50 psi), and I assume that would be useful in doing a dry storage procedure for the engine.

[Ron Hill]

Tom : I'm in Virginia (the not so frozen north!!) and I do BOTH methods of engine winterization!! 

I get one gallon of the lowest temperature grade engine winterization fluid.  Remove the raw water intake hose and stick it in the gallon jug.  Start the engine and let it suck all of fluid then shut off the engine.  Then I remove the Zn from the heat exchange so it drains all of the fluid out.  The fluid is in the muffler so you don't have to fool around with it.  Then I remove the impeller (spray it with silicone).  The engine is now set for winter!!  It's worked for over 30 years!!

A few thoughts

[tmac]

Ron, interesting about removing the zinc.  Is that more effective than removing the hose from the water pump to the HX?  I only ask since the hose is right on the front of the engine, and easier to get at. (I know, I know... the zinc is a regular maintenance item - I was going to address that next spring.) 
I'm surprised that just one gallon is sufficient to get all the way through to the muffler...

[Breakin Away]

A few comments, FWIW:

Blowing with a compressor must be done carefully, and done improperly is totally ineffective. Air will not push water uphill - it will just channel through the water. It is only effective if you can find and open all the low spots (yes, you might have more than one, and every one must be drained), then the air will push the water out. For this reason, I use some pressure on my domestic water system but still follow up with some antifreeze.

There is some debate about antifreeze type. I have never used ethylene glycol, opting only for the more expensive ethanol-free propylene glycol. However, there is some data that EG automotive antifreeze, while extremely toxic to mammals, may be no more toxic to aquatic life than PG. So some argue that EG could be used in non-potable things like air conditioners and heads. EG is also better for elastomeric seals and joker valves than PG. While I've never used EG to winterize any part of my boat, I do think about it every year.

In addition to draining the HX, I always drain the muffler before running the pink stuff through the motor. That can help reduce the dilution.

Draining as much water as possible is critically important. Even small amounts of water can drastically reduce the effectiveness of the pink antifreeze. I use a $10 refractometer to verify how the dilution affects the effectiveness, and it is SHOCKING how quickly the effectiveness is reduced, even when I take great pains to get the water out. I used to just "go by eye" looking at when it turns pink, but after using the refractometer I am convinced that going by eye is dangerous.

Hot water heater needs to be shunted off from the rest of the potable system, and needs to be carefully vented and drained. The impact of a freeze-up in the hot water system will not just ruin your day, it could disrupt your whole sailing season! After draining, I use a reversible Little Giant impeller pump to pump small amounts of antifreeze in and out of the heater. Each time it gets a little stronger and better protected. And you need to use caution with pumping air or antifreeze, because there are check valves at various places in the hot water system.

I no longer leave the pencil anode in my mostly-drained HX during the winter. Doing so leads to this very poor corrosion pattern:

[KWKloeber]

Ken - I'd be interested in seeing if your dry method is different than the manual.  I have a small compressor that I'm planning to use on the potable water systems (set at not more than 50 psi), and I assume that would be useful in doing a dry storage procedure for the engine.

Tom,

Thanks for your question. 

There's no need for no stinkin' compressor on the seawater side.

The first time I winterized her I didn't have a procedure from a manual, I simply figured out my cooling system and found every place that water could accumulate.  There's ONLY four. 
   
    The seawater pump.
   The Hx.
   The muffler.
   Hose between pump and Hx.

Those are the ONLY places where water can accumulate in OUR ENGINE.   Any hysteria or pending apocalypse about this if you don't pink it is just that.  Dire warnings from those who make a good buck doing this work for hands-off owners about water being left in the system somewhere magical that we don't know about is just that.  The complexity of the cooling on OTHER engines/exhaust systems can warrant flushing w/ pink, but not OURS.

After pumping pink thru and removing the impeller, how does antifreeze stay in the Hx?  What's the theory there?  Or does it stay in the muffler w/ the petcock open?

The REAL threat is NOT draining the water and using only pink stuff that is diluted and then freezes.  You're better off eliminating the cause of freezing than wanting to modify its properties so it doesn't.  It's like someone with a dead battery that will freeze -- so instead of just charging it to eliminate the issue they buy heat tape and a Space Blanket to keep it warm.  God Bless the OBOC (Others' Boats, Others' Choice) who still fear the hysteria and/or not fully understand OUR plumbing and/or just want to pink up anyway (just in case.)

   The exhaust hose is highest and drains to the transom after the high spot in the sail locker.  Besides any water left in it (and there isn't any) expands laterally along inside the hose, not radially and put pressure against the hose.

   The muffler is the low spot water accumulates there.
   The Hx is the high point at the engine and water in it will drain out (gravity does work.)
   My vented loop is higher and drains down to the Hx and muffler (I don't know about yours.)

So:

1. Open the petcock, drain the muffler, and leave it open (it's annual PM to check the petcock.)
2. Remove the Hx end caps, drain it, inspect the tubes (annual PM - run a wire through each one to make sure they're free of accumulated deposits.)  Sometimes I find grass has accumulated on the inlet end against the plate that the tubes are brazed to (I never had a strainer.)  SuperLube Gel or TefGel or Lanakote or whatever the hose barbs when reconnecting the hoses.
3. Get new or cut new end cap gaskets if they look questionable or swollen.
4. Flatten the caps if they are bent/cupped (AND don't overtighten them.)

I have also simply removed the hose at the seawater pump end, drop it down, and the Hx drains.  Yes, theoretically the Hx will not be perfectly level so it's belt/suspenders to remove both end caps (and especially for the PM reason.)

5. Pull the impeller (which is PM anyway)  (or pull the pump for inspection/service.)  Order a new impeller if the blades look questionable and use it in spring.  Save the best OLD one for another, just-in-case, "Oh crap, I forgot to open the thru hull after I replaced the torn impeller" kinda second spare.

Try it and you'll convince yourself plus you'll understand the plumbing better.
If you're not convinced simply put the inlet cap back on and run pink stuff thru the HX with a funnel using the seawater hose. and watch it and your cash run out the other end.  At worst, you have learned more about your engine.

    Save the pink stuff.
    Save the pumping.
    Save the bucketing.
    Save the refractometer (which is ALSO also unnecessary and a PITA, just use a PG antifreeze tester (or an EG one and look at a conversion chart of specific gravity).)
    Save the hassle.
    Spend the cash on beer.

If ANYone can (accurately) explain where else seawater can accumulate in our cooling system I will be pleased to explain how to remove it.

A compressor on the potable side is like a leaf blower, high pressure alone isn't what you need -- it's VOLUME per second, not PSI.  So you're better off w/ a large tank at lower pressure than the opposite.  You have to move water laterally in the hoses, which means FILL the hose with a continuous PLUG of air.  Too high a pressure and you may cause other issues.

At the pump, I replaced the fittings with thumb-turn-wing ones so I don't even need a wrench to drain the pump.

BTW w/ vinyl water hoses, the issue is the nylon FITTINGS.  Freezing weather won't burst our hoses because it expands laterally (and a little bit radially and the hoses GIVE.)  I'm not saying don't winterize or blow out the water or pink it (YUCK, some use cheap vodka), but we should know the facts about it.

Cheers

Off of the "Understand our engines instead of sticking our heads in pink sand" Soapbox

[tmac]

Again, thanks to all for the in-depth replies.  I won't enter into the "pink or no-pink" debate, as I see there are proponents on both sides, but I do have my own inclinations toward the simplest solution is often the best.  I've many decades of experience not only winterizing engines, but also our cabin plumbing, and landscape irrigation systems, and I know that "getting the water out" is really important up here where we often see -25 temps.  I'll have it all done this coming week, and start hunkering down for the long cold winter.  I'll be bringing home some of the teak to refinish over the winter, and might even take a stab at redesigning the saloon table.  I've seen all the older posts about that.
Maybe I'll also post photos of the transom platform I designed.  I custom machined hinges for it so that it can fold up, to avoid extra marina fees for boat length.  It was a really nice addition to the boat.

[Stu Jackson]

I'll be bringing home some of the teak to refinish over the winter, and might even take a stab at redesigning the saloon table.  I've seen all the older posts about that.

In addition to the older posts there are also tech notes.  I simply cut off about 6" at the aft end of my table - made a world of difference and kept the useful surface.  Depends on how you want to use the table. 

Your boat, your choice. 

[KWKloeber]

I'll have it all done this coming week,.

Groovy.  Let us know how it went for you!

[Ron Hill]

Tom : I use the -100F engine anti freeze and even if the gallon gets diluted to 50%, that is more than enough to winterize everything including the muffler.
I always take out the Zn from the HX in the fall and that drains the HX. Makes no since in leaving it with full fluid when you're going to "drain" it in the spring anyway - when you install a new Zn !!

On the salon table look in the Mainsheet tech notes /WiKi and you'll find a ZILLION different modification of the existing and newly designed salon tables!!
I cut the aft portion of the my table (toward the galley) making it into a drop leaf!!  That way it allows you to easily get at the starboard sliders/ storage when DOWN and when UP you still have the large table to easily seat 4/5 people!! 

A few thoughts