Finding he Freeze Plugs - Merc 3.0 I/O

[dmanmtl]

Guys,

I have read through many posts on the winterization process. This will be my first time doing this. I am mechanically inclined and understand the process involved pretty well. I live in Quebec, Canada and we get pretty brutally cold winters so I want to ensure this is done right.

I have a 2003 Bayliner 175 with a 3.0L alpha 1 gen2 drive. My biggest concern is findning all the freeze plugs. My engine has the two hoses connected to what looks like a handle coming up on the right side - I believe these are drain hoses but I am sure there are more plugs to pull out and clean out the holes. I have read that there could be 3 to 5 plugs on the block.

Since its a small boat the room in around the motor is not substantial, so I am wondering if someone can tell me how many plugs there are and their location...is there some sort of "schematic" somewhere that would help me find them all?

I am paranoid about missing something. I will probably also fill and drain with antifreeze just in case but I know thats not a fail safe and that draining is the only way to go.

Thanks in advance for your responses...

D

 

[achris]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

That sounds like you have the notorious 'Single point drain' system. Merc's quickest way to sell new engines.

The 2 hoses on the SPD system come from the block drain and the manifold drain. And that is all you have on the 3 litre block, just those 2. What I would do, is pull the hoses off the fittings that are in the block and manifold. Get in there with a piece of wire, small screwdriver or a nail and make sure the holes are clear and all the water flows out. There's about 10 litres in the block alone, and a bit less in the manifold.

I would also add to that remove the big hose from the water pump and let that drain too. (all this should be done with the boat level or slightly bow up). There is also a hose that runs from the transom plate to the water distribution block at the front of the engine. Once the drive is off (I assume you'll be removing the drive and storing it somewhere else) I would remove that hose from the engine end and hold it up for all the water to drain and drop out of the water passage in the bell-housing (that's why you can't do it with the drive in place, won't drain)... There may also be a small brass plug in the exhaust elbow. If there is, remove that one too....

My personal preference is to leave all the drains out and the hoses off. Put the drain plugs in a small bag and tie it to the steering wheel...

One other thing I would do, pull the spark plugs and drop a bit of 2 stroke oil down each hole. Put the plugs back in and give the engine a couple of turns with the starter to distribute the oil. That will protect the cylinder walls for the duration...

Good luck. Oh, BTW, I'm an 'Air don't freeze' kinda guy...

Chris........

 

[dmanmtl]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

Chris,

Thanks for your reply. You mention removing the outdrive and storing it somewhere - I wasn't planning on doing that. I will change the oil in it but would prefer to leave it on the boat. Is there a reason why you would suggest this?

Also, you mention that the single point drain system is "notorious" - why is it ? I am assuming it does not drain properly...I will research that a bit.

Again thanks for the great reply.

D

 

[achris]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

You should really be removing the drive to do the annual service items in that area too. Grease gimbal bearing, grease unis, check engine alignment, check condition of bellows, etc, etc.I just thought with winter being 'brutal' it would be better to store the drive somewhere a little 'nicer', like a basement of garage... (If it was mine, it would be in the living room , but I think the wife would object. )... You can drain that hose while you have the drive off, then put it back on...

Yes, the SPD system is notorious for getting blocked up and the engine doesn't drain out properly. Water in winter, crack in spring. That's why most people pull the hoses from the block fittings...

Chris......

 

[oldjeep]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

I've never seen or heard of anyone storing the drive off the boat and we have some of the most brutal winters around.

The 3.0L SPD system is about as simple as it gets - a direct hose off where the drain **** would normally be. If there is water flowing out then it is no different than if there were drain cocks. If the water does not flow out then it is the same fix as if there were (poke around up there with a wire).

I leave the hoses down for the winter and reconnect them in the spring. As far as "most people" removing them - no way in hell. They have sold tens of thousands of these things in my state alone, never heard of anyone pulling the hoses off.

The SPD drain system that is actually notorious is the one that they put on v8's where you have 8 hoses going to a manifold with a single drain - those you can't tell if any one point actually drained out or was plugged.

 

[Lou C]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

That would never work in salt water if the engine is raw water cooled, I always have to probe the drains because of the 4 of them one is always clogged with rust flakes.
The bottom line is that all inboards should at least have a half closed cooling system, if not a full system. When my boat gets a new motor for sure I will put one on. I am done with sticky thermostats, draining the block, wondering when it will rust through, etc. GM did not intend for Chevy engines to have salt water running through them. Cheap boat companies...In fact, this is one area where an inboard could be better than an OB, which can't be closed cooled.

 

[oldjeep]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

I don't think that Quebec has much salt water.

 

[Lou C]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

Freshwater can be pretty corrosive too depending on the mineral content.

the only good thing about open cooling is that it is simple, less to go wrong and cheap.
closed cooling your engine will easily last 2x as long because of less corrosion and it runs closer to the temp it was designed to run at.
open cooling often has the problem of sticky thermostats then the engine runs too cold and the choke does not open when it should. causes increased wear.

 

[dmanmtl]

Re: Finding he Freeze Plugs - Merc 3.0 I/O

Guys - thanks for all your replies. I have removed the two drain hoses drained the water, filled with antifreeze through the hoses - twice - drained again and think I'm good to go - Haven't decided yet if I will tackle removing the leg - from what I read it sounds pretty simple, but nothing is ever as easy as it is made out to be.

Wish I had waited a week - going to be 70F and sunny here this weekend - would have been a great weekend to be out on the deserted lake!

D