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Are my winterization steps good for my 2003 4.3 MC engine?

J

Jason Denzel

New member
I live in Leadville, CO. This boat only goes in fresh water high mountain reservoirs. The engine is a 4.3 LITRE Thunderbolt V ignition Mercruiser. I a m sick of driving 40 miles one way and paying $200 for winterization which is what the only boat repair shop in my area charges. I made it a mission of mine to learn how to do this myself this year. I am not mechanically inclined so it has scared me off for years. So…. After looking at all kinds of steps and instructions I have made this list. I store my boat in a garage non heated. I live in a below zero degrees environment at certain times of the winter. Can you guys let me know what you think? Thanks!!

Winterization steps for 2003 bayliner runabout 4.3 liter Mercruiser
1. Add gas stabilizer to tank and top off
2. Install ear muffs to outdrive with hose.
3. Turn on water and start engine. Let run until temp guage is reading normal or 30 minutes to be 100% safe. (t-stat is open) This allows good flushing of the engine.
4. Turn off engine and water.
5. Change oil, oil filter with pump,(gas filter, and out-drive lube) optional?
6. Turn water back on and start engine. Check for leaks.
7. Turn off engine and water.
8. Locate all drain plugs on engine and remove. There are 5 blue butterfly plugs on the 2003 bayliner
9. Disconnect all hoses from t-stat housing and pour antifreeze into each util see coming out drains.
10. Install all drain plugs.
11. Remove hose from ear muffs and hook up hose to sub pump.
12. Reinstall hoses to t-stat.
13. fill a 5 gallon bucket with 4 gallons of RV AF. Drop Subpump with garden house connected to muffs connected to water intake on motor. Have 2+ gallons at the ready for adding more.
14. Turn on the pump, then start the engine. have someone hold ear muffs semi tight to conserve AF. (You will also need to keep an eye on the volume in the bucket and start taking those spare gallons you opened ahead of time and start pouring more AF into the bucket. Make sure the bucket doesn't run dry.)
15. Verify antifreeze is coming out 2 side ports at transom assy on outside.
16. Spray fogging oil into carb.
17. Turn off engine. Besure to reach this step before tank runs out of antifreeze.
18. Engine is now done. Clean up.
19. disconnect and remove batteries. Store in warm area
20. Clean boat. Vacume, armour all all vinyl, clean windows
21. Cover boat losely with boat cover
22. Store in non-heated garage
 
Step 8A Probe openings to insure draining.
No 9
Step 10 OK
No 11
Step 12 OK
Skip 13,14,15,16,17
Step 18 - 22 OK


Simply pour the A/F into the engine and manifold
 
Fuel stabilizer best added just before you fill tank for last time, preferably while boat is in water so you can rock (or run the boat for a short distance) to get complete mixing.
 
Bt Doctur said:
Step 8A Probe openings to insure draining.
No 9
Step 10 OK
No 11
Step 12 OK
Skip 13,14,15,16,17
Step 18 - 22 OK


Simply pour the A/F into the engine and manifold
Click to expand...

So you are saying do not remove the 5 plugs that drain the water from the engine? What locations do I pour the AF into to hit the engine and manifold?
 
Nowhere did I even mention that.8a is after 8. remove the plugs and probe the holes to ensure it does drain.
remove the large hose that goes from the circ pump the therm housing at the housing and pour the A/F in untlll it comes
out the housing. remove the 2 manifold hoses from the therm housing that go to the bottom of the manifolds and pour the a/f in untill it runs out the exaust
 
my process

1 add stabil to gas (how much depends on how much gas)
2 shake boat to mix stabil
3 outdrive down and install muffs/water on and run motor till operating temp (approx. 15 mins) If you feel the need to fog the motor do it now and do it for about 2-3 minutes before shutting engine off. (Note: I personally never fog a 4 stroke motor unless the customer insists on it, I have never fogged my 1987 V8 since owning it 1995 - present, NO ISSUES).

4. shut motor off and remove muffs, outdrive is self draining when down

5. pull all the butterflys and poke thru if little or no water comes out.

6. pull incoming water hose to thermostat housing off at thermostat housing (the hose comes from the transom to Tstat housing it should have the power steering cooler in line with the hose), pour rv anti freeze into hose and force all water back out thru outdrive until you see pink (rv antifreeze color ) running out of drive. This takes several fill ups on hose as it takes time to push the water out.

7. remove all other hoses from thermostat housing, large hose from housing to water pump, bend down to drain residual water out, two or four hoses going to manifolds/elbows should also be removed from Tstat housing,

8. once block and manifolds are drained (give it about 20 minutes) put butterflys back in.

9. pour antifreeze into the manifold/elbow hoses, Approx 1/2 gallon divided by the two or four hoses.

10 pour 1/2 gallon into large hose (this fills the block partially)

11. pull transom drain plug to allow water to drain out of boat and put the drain plug into cup holder

Now if you feel the need to change your motor oil and outdrive gear oil do it now.

Once done with oil changes raise outdrive and disconnect battery ( I leave my batteries disconnected in the boat but that is a personal choice)

DONE.

No need to run motor again after oil changes........wait until spring.......

I think that is it.............

There is no need to run a motor in a tub full of antifreeze............If you want to then go ahead but it is a lot of work....

If mercury thought that was the correct method they would not have drain plugs...............

Just my opinion after winterizing 1000's of boats...............
 
Seems like that's the hard way. I drain everything, run pink stuff through (with the motor running) until it comes out the exhaust, then shut down. I then pull the coil wire and fog the motor for about 15 second on the starter. Simple, easy to do, and safe since there's no pockets of water trapped inside there.

I used to pull the T-stat as well until I realized my engines have a by-pass circuit around a closed T-stat, which means the coolant goes through even with it closed.

Jeff
 
In my opinion, when running antifreeze only thru a running motor does not guarantee a water free motor.

you are assuming the thermostat opens and allows the antifreeze to circulate thru out the engine and ALL the water exits the block.

when running only antifreeze into the motor most if not all initially runs out the elbow to cool the exhaust.

If it were that simple mercury would not put drain plugs in the block or manifolds.
 
kghost said:
my process

1 add stabil to gas (how much depends on how much gas)
2 shake boat to mix stabil
3 outdrive down and install muffs/water on and run motor till operating temp (approx. 15 mins) If you feel the need to fog the motor do it now and do it for about 2-3 minutes before shutting engine off. (Note: I personally never fog a 4 stroke motor unless the customer insists on it, I have never fogged my 1987 V8 since owning it 1995 - present, NO ISSUES).

4. shut motor off and remove muffs, outdrive is self draining when down

5. pull all the butterflys and poke thru if little or no water comes out.

6. pull incoming water hose to thermostat housing off at thermostat housing (the hose comes from the transom to Tstat housing it should have the power steering cooler in line with the hose), pour rv anti freeze into hose and force all water back out thru outdrive until you see pink (rv antifreeze color ) running out of drive. This takes several fill ups on hose as it takes time to push the water out.

7. remove all other hoses from thermostat housing, large hose from housing to water pump, bend down to drain residual water out, two or four hoses going to manifolds/elbows should also be removed from Tstat housing,

8. once block and manifolds are drained (give it about 20 minutes) put butterflys back in.

9. pour antifreeze into the manifold/elbow hoses, Approx 1/2 gallon divided by the two or four hoses.

10 pour 1/2 gallon into large hose (this fills the block partially)

11. pull transom drain plug to allow water to drain out of boat and put the drain plug into cup holder

Now if you feel the need to change your motor oil and outdrive gear oil do it now.

Once done with oil changes raise outdrive and disconnect battery ( I leave my batteries disconnected in the boat but that is a personal choice)

DONE.

No need to run motor again after oil changes........wait until spring.......

I think that is it.............

There is no need to run a motor in a tub full of antifreeze............If you want to then go ahead but it is a lot of work....

If mercury thought that was the correct method they would not have drain plugs...............

Just my opinion after winterizing 1000's of boats...............
Click to expand...


This way definitely seems less wasteful. Yea it always seem to me that the earmuff with pressured AF running through it was a sloppy way to go about it. Funny there are so many youtube videos that show it done this way when you search "winterize mercruiser". I think I like your method better though. I am going to try it out this weekend. Thanks!
 
........................

Jason Denzel said:
I live in Leadville, CO. This boat only goes in fresh water high mountain reservoirs. The engine is a 4.3 LITRE Thunderbolt V ignition Mercruiser. I a m sick of driving 40 miles one way and paying $200 for winterization which is what the only boat repair shop in my area charges. I made it a mission of mine to learn how to do this myself this year. I am not mechanically inclined so it has scared me off for years. So…. After looking at all kinds of steps and instructions I have made this list. I store my boat in a garage non heated. I live in a below zero degrees environment at certain times of the winter. Can you guys let me know what you think? Thanks!!

Winterization steps for 2003 bayliner runabout 4.3 liter Mercruiser
1. Add gas stabilizer to tank and top off
Add fuel stabilizer, and take the boat/trailer for a ride down a not-so-smooth road.
This will mix the stabilizer with the remaining fuel.

2. Install ear muffs to outdrive with hose.
3. Turn on water and start engine. Let run until temp guage is reading normal or 30 minutes to be 100% safe. (t-stat is open) This allows good flushing of the engine.
Why flush an engine that has been in fresh clean lake water???
Drain the remaining lake water.... and you'll be just fine.

4. Turn off engine and water.
5. Change oil, oil filter with pump,(gas filter, and out-drive lube) optional?
Change oil and filter cartridge, run engine and look for any leaks near the oil filter.

6. Turn water back on and start engine. Check for leaks.
7. Turn off engine and water.
8. Locate all drain plugs on engine and remove. There are 5 blue butterfly plugs on the 2003 bayliner
As said... be sure to probe these drain ports.
Rust scale can and will build up, often preventing complete draining unless these ports are probed.

9. Disconnect all hoses from t-stat housing and pour antifreeze into each util see coming out drains.
Just plain ole Air won't freeze expand and cause damage to your expensive cast iron components.
Adding antifreeze will give you that "feel good" feeling only!
The amount of rust that will occur during the layup period, will be paled by comparison to that of the rust duing the normal season.

10. Install all drain plugs.
Leave drain plugs out.
Place bag of plugs and note on helm wheel stating what you've done!

11. Remove hose from ear muffs and hook up hose to sub pump.
12. Reinstall hoses to t-stat.
13. fill a 5 gallon bucket with 4 gallons of RV AF. Drop Subpump with garden house connected to muffs connected to water intake on motor. Have 2+ gallons at the ready for adding more.
14. Turn on the pump, then start the engine. have someone hold ear muffs semi tight to conserve AF. (You will also need to keep an eye on the volume in the bucket and start taking those spare gallons you opened ahead of time and start pouring more AF into the bucket. Make sure the bucket doesn't run dry.)
15. Verify antifreeze is coming out 2 side ports at transom assy on outside.
NO, NO and NO to 11, 12, 13, 14 and 15!
Please read this write up.
http://www.amazon.com/review/R3BD7X6QC3KCFR/ref=cm_cr_pr_viewpnt#R3BD7X6QC3KCFR

16. Spray fogging oil into carb.
Fog the carbureted engine during your short start-up for oil filter leak checks. (DO NOT fog an FI engine!)
You can properly fog a carbureted V engine in 10 seconds or so.
Be sure to spray the fogging solution equally into each primary throttle bore (V engines).
If you miss one intake manifold plane, you will have missed 50% of your cylinders.

17. Turn off engine. Besure to reach this step before tank runs out of antifreeze.
18. Engine is now done. Clean up.
19. disconnect and remove batteries. Store in warm area
A good, fully charged battery (when disconnected properly), will survive the winter.

20. Clean boat. Vacume, armour all all vinyl, clean windows
21. Cover boat losely with boat cover
22. Store in non-heated garage
Click to expand...


.
 
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Jason Denzel said:
This way definitely seems less wasteful. Yea it always seem to me that the earmuff with pressured AF running through it was a sloppy way to go about it. Funny there are so many youtube videos that show it done this way when you search "winterize mercruiser". I think I like your method better though. I am going to try it out this weekend. Thanks!
Click to expand...


One thing to note:

If you are not confident on removing the plugs, draining and reinstalling the plugs then before reinstalling the plugs pour some antifreeze in each hose (one at a time) and look for the antifreeze to come out of the, side of the block, manifold.



Youtube can be very informative...............BUT I will say with complete and total confidence.

I have personally winterized well over 1000 boats, maybe closer to 2000 + in the last 25 years.......NEVER had a failure!!
So I know my way of winterizing works...............


If you have questions ask before you finish just to be sure you did not miss anything

Aside from running the motor to circulate the stabil into the carb, the winterization should only take about 1/2 hour.

Also remember to reinstall all the hoses to there correct locations and don't use a screw driver to loosen and tighten the hose clamps.

USE A NUT DRIVER!!
 
OK

I just went out to winterize my boat. I lowered the outdrive, connected the muffs, turned water on, put stabil in gas, danced in the boat for a couple of minutes, Started the motor, let run for 10 minutes at 1500 rpms, shut it off, pulled muffs off and shut water off, pulled 4 plugs, two motor, two manifolds,(hot) removed 4 hoses from Tstat housing, waited for block and manifolds to drain, put plugs back in, poured about 1/3 gallon of antifreeze (RV PINK) into water supply hose to push water back out thru power steering cooler and out the outdrive, Poured 1/4 gal into each manifold/elbow hose, poured remainder into large water hose going to water pump on front of motor. Removed cover over carb and wiped clean the flame arrestor for sh!ts and giggles.

Pulled transom plug put in cup holder, raised trailer as high as it would crank up then raised outdrive all the way up and hit the down button once to relieve pressure on up valve. Put mooring cover back on.

Will disconnect batteries and remove stuff in boat on a later date.

Total time..........30 minutes from start to finish. Boat motor will be safe until spring.

I do all my oil changes in the spring. Especially the outdrive. When I service the outdrive in the spring I drain and pressure check to 15 psi before refilling. Seals can go bad over a long cold winter.........if the drive is not serviced in the spring one will never know if a seal has gone bad until it is too late!

I also change my motor oil in the spring. I find it is easier to all at once that is what I would call part of a spring service....


After servicing thousands of boats in the spring and seeing all the seal leaks found in the drives before customer could use the boat I am convinced that this is the only true way to service a outdrive..........Not in the fall but in the spring before use. It is the only way to be sure.


Oh and total cost for winterizing my boat today

Under $10.00............One pint of stabil and one gallon of RV antifreze
 
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.."In my opinion, when running antifreeze only thru a running motor does not guarantee a water free motor."

The block and etc. have been drained, so any water left inside is thoroughly diluted. Also--even with the t-stat still in place--coolant fills the block. I had to suck in 3 to 4 gallons of Pink Stuff per motor before any came out the back.

Done several V-8s in this fashion and everyone survived several severe winters.

Jeff
 
Again....a lot of material and a lot of set up to do more than what is needed.

Some say I over do it.......


once the block and manifolds are drained not much can go wrong. Adding a bit of RV is just a bit of insurance........

if it is a boat owners only boat then "what ever floats your boat"..........for me and my method that I have been using for a long long time it works for me.........and many others.........


FYI we used to have a "assembly line" of boats in the fall at our marina (fresh water lake) (no salt water crap).........No way could we put each one in a drum of antifreeze and run it......not enough time in a day........


When the boat came out of the water we drained it, antifreezed it and disconnected the battery then bottom washed it with oxcylic acid and hot water and scrubbed the oil/gas line off the side then shrink wrapped it.......All in about 1 1/2 hrs non stop every day for a couple of months......

Assembly line work........very hard and demanding..........We did several hundred boats per month or more this way every year after year.......


So even though I don't work that way any longer I still use the same basic method............
 
This has been said over and over again....

"just plain ole air won't freeze expand and crack our expensive cast iron components."

Drain down your engine block, cylinder heads, intake manifold, circulating pump, exhaust manifolds and elbows, and any component that could hold seawater.

Probe the drain ports to ensure that no rust scale is preventing complete draining.
(it is physically impossible for air to freeze expand and crack cast iron!)

If you are Hell Bent on using AF for winterizing and/or corrosion prevention/protection, at least drain it again afterwords.
This will eliminate any possibility of AF dilution that may cause an issue.



Edit:

For those who may have the single point drain systems, get rid of them!
The drain ports cannot be properly probed with these systems.
I've replaced engines from the owners or mechanics having used the single point drain systems.


.
 
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Air plus moisture all winter long creates RUST inside the motor. Fill it with Pink stuff and it won't rust. Think about it.

Jeff

PS: All....winter...long!
 
Jeff, I don't disagree with you.
However, the amount of rust that could occur during the lay-up will be paled by comparison to that of the rust that occurs during the normal boating season.
For me, this is a moot point to try and prevent.

If we are after that "feel good feeling", then by all means add the AF.

But again.... this is all my opinion only. Do what you're comfortable with.



.
 
Thanks for all the great advice everyone. Especially your detailed instructions KGhost! I am going to try your method today. Got my stabil, AF, and hoses to fill up all the areas.
 
So I wanted to attach some pics of what I did. I took all 5 plugs out which are not in this pic (too hard to take pics of those. I let them all drain thoroughly. I took off the 4 hoses shown in the pic. let those drain (although there was not much to drain after the plugs. I poured AF into each of the 4 hoses. Mostly 1/4-1/2 gallon per hose. I did notice AF coming out the back once filled on 3 of the 4 hoses. The one hose did not seem to empty out the back like the others did. I must have poured over half a gallon in this one. so I called it good there. This hose was the bottom left (bigger) hose. reconnected the hoses. From my description and pics can you tell if I am missing anything?

I also sprayed fogging oil into carb till engine stopped. This was done before all of the above.


Engine hoses.jpg
 

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The big hose feeds the block. in reality that is the motor to motor water pump recirculation hose so the AF went into the motor.

the two hoses closest to the carb go to the bottom of the manifolds. Once you drained the manifolds and put the plugs back in the AF filled the maifolds and if enough was put in the AF would run out the exhaust through the elbows/risers...

the right hand side the hose across from the large one is the INCOMING water supply to the motor from the water pump impeller in the out drive.

There is also a power steering cooler in line in this hose (small black metal tube with two small black hoses connected to it from the power steering pump (front of motor) and the power assist attached to the steering cable at the transom. This hose if the power steering cooler is lying horizontal then the water needs to be pushed back thru to the out drive. This is where I said it may take a few fill ups on the hose to push the water back as that hose may be full up to the Tstat housing with water when disconnected.

Where was the 5th plug????

the block should have had 2 one on each side, the manifolds should have had 2 one on each side.

Where was the 5th?
 
Sucks to be you........whom ever designed that motor hole should be shot! no room to work on the motor from what I can see.

I hate motor holes designed that way............it hurts your body when working on them....lol
 
I can take pictures of that 5th plug.

So for that incoming waterline hose, should I fill it up till either it pours out somewhere else or fills up the hose to the top entirely? just want to be safe.
 
The incoming water hose needs to be filled up until the antifreeze comes out the outdrive where the water gets sucked in. The lower unit where the two inlets are on each side. If the water is not pushed back all the way the power steering cooler could pop over the winter.

If the 5th plug was for the cooler then you already drained it and no need to go any further.....

The other hoses are just insurance and will most likely not make much difference.
 
Ok, so here are all 5 plugs. 2 on each side that seem identical location for each side. I am assuming these are the block and manifold drains. The 5th one in question is the easiest one to reach in the front. It is the drain for the largest hose front left and it is right at the elbow where it goes into the engine.



5th.jpgright_side_1_and_2.jpgleft_side_3_and_4.jpg
 
Yes that is all accurate

The one on the large hose (from motor water pump to block) is a newer design, I mentioned to bend this large hose to drain residual water from it, well Merc put a plug in it so bending is no longer necessary.

So recheck the other hose across from the large one at the thermostat housing and pour antifreeze into it make sure you see antifreeze come out of the lower unit at the intake ports one each side on the out drive. When you see this then you have back flushed the incoming water line with antifreeze completely.
 
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