Winterizing Merc 5.0L EFI's While In Water

[PlanB]

I have a 55' houseboat with twin 5.0L EFI Mercruisers with Bravo II's that stays in the lake. I have a shutoff valve in the hose from the outdrive to the seawater pump and open top strainers. To winterize this fall I want to shut off the valves, pour antifreeze solution in the strainers. I did this last winter. I ran the motors up to temperature, then poured antifreeze in until it came out the outdrive. When I later checked the lower drain plugs in the block and there was still clear water in the block. I think I ran about 6 gallons of solution through. Did I not use enough antifreeze solution? The reason I want to do this is that the blue drain plugs are very hard to get to and it gets harder for me the older I get.

Any suggestions would be appreciated.

Rick

BTW I emailed Mercury Marine and the tech rep told me that they do not recommend customers doing their own winterizing and to take it to an authorized service center where they can run it in a winterization tank. Yeah, I'll run this 55' x 16' wide puppy on the trailer and do that.

 

[Bondo]

Re: Winterizing Merc 5.0L EFI's While In Water

I have a 55' houseboat with twin 5.0L EFI Mercruisers with Bravo II's that stays in the lake. I have a shutoff valve in the hose from the outdrive to the seawater pump and open top strainers. To winterize this fall I want to shut off the valves, pour antifreeze solution in the strainers. I did this last winter. I ran the motors up to temperature, then poured antifreeze in until it came out the outdrive. When I later checked the lower drain plugs in the block and there was still clear water in the block. I think I ran about 6 gallons of solution through. Did I not use enough antifreeze solution? The reason I want to do this is that the blue drain plugs are very hard to get to and it gets harder for me the older I get.

Any suggestions would be appreciated.

Rick

BTW I emailed Mercury Marine and the tech rep told me that they do not recommend customers doing their own winterizing and to take it to an authorized service center where they can run it in a winterization tank. Yeah, I'll run this 55' x 16' wide puppy on the trailer and do that.

Ayuh,.... Unless you'd rather swap out the motors every year,...
I suggest you figure out HOW to Drain everything onboard that has water in it...

Obviously, yer plan Don't work...

Btw,... There ain't no shortcuts from doin' things Right...

 

[PlanB]

Re: Winterizing Merc 5.0L EFI's While In Water

Ayuh,.... Unless you'd rather swap out the motors every year,...
I suggest you figure out HOW to Drain everything onboard that has water in it...

Obviously, yer plan Don't work...

Btw,... There ain't no shortcuts from doin' things Right...

I know how to "Do it right." I had this boat custom built and have owned it for 10 years. Draining all six blue drain plugs then filling the motor up with antifreeze solution through the thermostat housing is the way I have done it. It is just a real PITA. And at 62 it gets to be a bigger pain each year. I have had 20 boats in the last 40 years and many could be winterized by running solution through the raw water intake. I see no reason why what I am attempting will not work. I am just curious why is isn't getting the antifreeze to the lower block. I am really thinking that I just need to use more solution, like maybe 10 gallons per engine.

 

[Bondo]

Re: Winterizing Merc 5.0L EFI's While In Water

I know how to "Do it right." I had this boat custom built and have owned it for 10 years. Draining all six blue drain plugs then filling the motor up with antifreeze solution through the thermostat housing is the way I have done it. It is just a real PITA. And at 62 it gets to be a bigger pain each year. I have had 20 boats in the last 40 years and many could be winterized by running solution through the raw water intake. I see no reason why what I am attempting will not work. I am just curious why is isn't getting the antifreeze to the lower block. I am really thinking that I just need to use more solution, like maybe 10 gallons per engine.

Ayuh,... The antifreeze yer dumping into the lake is Cold....
As soon as it hit's the T-stat, the T-stat closes, 'n you continue to dump the antifreeze into the lake....

I winterize everything by Draining the water,...
Air, Don't Freeze...
No need what so ever to be polluting yer pond with Antifreeze...

I know it sux gettin' old,...
I'm not far behind ya...
But,...
Sometimes there ain't no way to do a job Right, and Easier...

I suggest you continue Draining everything, 'n ditch the antifreeze...
If ya can't reach the drains to remove 'em, 'n poke the holes clear,...
Hire a smaller, younger person to Help ya...

Antifreeze Kills fish, 'n does absolutely NOTHING fer yer motors...

 

[natemoore]

Re: Winterizing Merc 5.0L EFI's While In Water

Diffusion: molecules of matter will spread from areas of high concentration to areas of lower concentration, eventually becoming evenly distributed within the container. Unless that area of the block is a separate system, then the anti-freeze will get there.

I guess the thermostat remains closed and separates the block into two systems.

Is it easy to remove the t-stat?

 

[PlanB]

Re: Winterizing Merc 5.0L EFI's While In Water

Mercruiser recommends adding antifreeze for added protection. I also like doing that if there is a pocket of water left somewhere. I use a non-toxic antifreeze with anti-rust additives.

The antifreeze solution I use is the same temperature as the lake water or warmer and I add it with 1 minute of closing the valve and pouring it in.

 

[Bondo]

Re: Winterizing Merc 5.0L EFI's While In Water

The antifreeze solution I use is the same temperature as the lake water or warmer and I add it with 1 minute of closing the valve and pouring it in.

Ayuh,... Unless yer antifreeze is ABOVE the Temp rating of the T-stat,...
The T-stat is gonna Close....

Btw,... "I use a non-toxic antifreeze with anti-rust additives."

That's not NON-toxic, just abit Less toxic...

I doubt yer up to drinkin' either 1 of 'em....

 

[natemoore]

Re: Winterizing Merc 5.0L EFI's While In Water

Antifreeze Kills fish, 'n does absolutely NOTHING fer yer motors...

Don't they make environmentally safe anti-freeze yet?

 

[Gettinther]

Re: Winterizing Merc 5.0L EFI's While In Water

Mercruiser recommends adding antifreeze for added protection. I also like doing that if there is a pocket of water left somewhere. I use a non-toxic antifreeze with anti-rust additives.

The antifreeze solution I use is the same temperature as the lake water or warmer and I add it with 1 minute of closing the valve and pouring it in.

Is there any enviromental protection agencies around you? If there is show them what and how you use this anti-freeze and additives and see if they agree with dumping this chemical coctail in the lake.:facepalm:

I know I'm not answering your question but you sure raise a lot more

 

[Don S]

Re: Winterizing Merc 5.0L EFI's While In Water

Mercruiser recommends adding antifreeze for added protection.

True, but you missed one important part. They do NOT recommend putting it in the engine by running the engine. If you look at your owners or service manual you will see it tells you to drain the system first, then remove the thermostat housing and pour antifreeze into the engines cooling system.

 

[HT32BSX115]

Re: Winterizing Merc 5.0L EFI's While In Water

Howdy,


Dumping anti-freeze into the raw water intake of a raw water cooled engine is problematic because even when the t-stat is fully open, you do not get the same concentration in the block as you pour in.

MOST of the raw water from the raw water pump bypasses the engine altogether and gets dumped overboard out the risers.

You would have to know how much water is in the block before you start it and use the same amount of 100% A/F going into the raw water intake to get a 50/50 in the block. THEN you would have to recover ALL the discharge water from the riser output and recirculate it back through the raw water intake.

Because only a small amount of water actually gets mixed in to the block (recirculating) water it would take quite some time running the engine with the t-stat fully open (or removed) to ensure that you had the right "mix" IN the block.

Your t-stat is not NOT fully open, and even if it is, most of what you pour in is still going overboard.


What you're doing is pretty risky depending on how cold it gets there.Since you probably have a small fortune in this boat, you could spend a little more and put closed cooling on each engine. (that's what I did to mine.....but maybe the engine are too old/too many hours etc) Then you would only have to drain the heat exchanger and other raw water components.


I would just pay someone to open the drains. It will most definitely be cheaper than new engines and manifolds.......


Regards,


Rick

 

[PlanB]

Re: Winterizing Merc 5.0L EFI's While In Water

Is it easy to remove the t-stat?

Yes, it is right on top and removes with two bolts. I guess the next suggestion would be to take the stat out when running the antifreeze through?

 

[Bondo]

Re: Winterizing Merc 5.0L EFI's While In Water

Yes, it is right on top and removes with two bolts. I guess the next suggestion would be to take the stat out when running the antifreeze through?

Nope, not really,...

Yer missin' the Most Important part of winterization, whether as We do it here, or per the factory manual...
It HAS to be Drained 1st....

 

[PlanB]

Re: Winterizing Merc 5.0L EFI's While In Water

[/B][/I]What you're doing is pretty risky depending on how cold it gets there.Since you probably have a small fortune in this boat, you could spend a little more and put closed cooling on each engine. (that's what I did to mine.....but maybe the engine are too old/too many hours etc) Then you would only have to drain the heat exchanger and other raw water components.

I have only tried this once and when it didn't work I drained and winterized the old fashion way.

I asked the builder about closed cooling when the boat was built and he talked me out of it. My Westerbeke genset is closed cooling and it is a snap to winterize through the strainer.

I would just pay someone to open the drains. It will most definitely be cheaper than new engines and manifolds.......

Opening the drains is not the pain. Getting the little blue plastic wing nut plugs back in is the pain. They break, the o-rings fall off, they are hard to get started in the thread and easy to cross thread. All of this to deal with while having to contort my old carcass.

If I had old fashion radiator type draincocks this would be no issue. I have 6 plugs per engine. The manifolds and circulation pump are not a problem. The two on either side of the block are a pain as well as one in the fuel cooler. The Merc plugs are an odd 1/2 - 13 thread. I have looked for adapters or 1/2 - 13 draincocks with no luck.

 

[Bondo]

Re: Winterizing Merc 5.0L EFI's While In Water

Opening the drains is not the pain. Getting the little blue plastic wing nut plugs back in is the pain. They break, the o-rings fall off, they are hard to get started in the thread and easy to cross thread. All of this to deal with while having to contort my old carcass.

If I had old fashion radiator type draincocks this would be no issue. I have 6 plugs per engine. The manifolds and circulation pump are not a problem. The two on either side of the block are a pain as well as one in the fuel cooler. The Merc plugs are an odd 1/2 - 13 thread. I have looked for adapters or 1/2 - 13 draincocks with no luck.

Ayuh,... Take the plastic plugs, 'n the piece they screw into, 'n Toss 'em overboard...
Then go to yer local hardware store, 'n get plain ole brass pipe plugs...
Most, if not all of yer drains are 1/4" pipe thread, at the point they screw into the iron parts...
If by chance 1 or more is smaller, it's 1/8" pipe thread...

 

[PlanB]

Re: Winterizing Merc 5.0L EFI's While In Water

Nope, not really,...

Yer missin' the Most Important part of winterization, whether as We do it here, or per the factory manual...
It HAS to be Drained 1st....

I am not missing it, just digging for some other alternatives. Draining is the issue (See post above about the little blue Merc plugs.)

 

[Bondo]

Re: Winterizing Merc 5.0L EFI's While In Water

I am not missing it, just digging for some other alternatives. Draining is the issue (See post above about the little blue Merc plugs.)

Ayuh,... I'm ahead of ya, see the post above yer's....

 

[PlanB]

Re: Winterizing Merc 5.0L EFI's While In Water

Ayuh,... Take the plastic plugs, 'n the piece they screw into, 'n Toss 'em overboard...
Then go to yer local hardware store, 'n get plain ole brass pipe plugs...
Most, if not all of yer drains are 1/4" pipe thread, at the point they screw into the iron parts...
If by chance 1 or more is smaller, it's 1/8" pipe thread...

I have thought about that, but the brass plug fittings on the starboard side have an antiknock sensor attached to that fitting also. The Merc manual is very adamant about not disturbing this sensor. What I need is a draincock that will fit the existing brass fittings.

 

[Bondo]

Re: Winterizing Merc 5.0L EFI's While In Water

I have thought about that, but the brass plug fittings on the starboard side have an antiknock sensor attached to that fitting also. The Merc manual is very adamant about not disturbing this sensor. What I need is a draincock that will fit the existing brass fittings.

Ayuh,... The knock sensor is merely mounted in a 1/4" brass "T"....

Swap the fittings to ALL 1/4" pipe thread...

Both the Block, 'n the sensor are 1/4" pipe thread...

 

[PlanB]

Re: Winterizing Merc 5.0L EFI's While In Water

Ayuh,... The knock sensor is merely mounted in a 1/4" brass "T"....

Swap the fittings to ALL 1/4" pipe thread...

The knock sensor is actually mounted on a brass "Y" if that makes any difference. Perhaps due to a clearance issue for the sensor? Maybe using a longer stem and a "Tee" would work. These engines are 305 CID. Merc quit using them for a couple of years but brought them back in 2001. I think Merc used a GM base block up to about 1997 but not sure where the got them when they brought them back around 2001.