3 questions about winterizing a 3.0 Mercruiser

[pontooner]

I am new to inboard/outboard motors. I have a pontoon with a 3.0 mercruiser and an alpha 1 outdrive.
1. How cold does it have to be before the engine block could crack?
2. Where are the plugs that need to be removed for winterizing?
3. Can't I just dry start it for a couple of seconds and blow out the extra water?

I know that I should probably get a manual for this, but it is supposed to get down to freezing tonight (30 - 32 degrees).

Besides, you guys seem to know more than most manuals do.

Thanks in advance for any assistance that you can provide.

 

[imported_TheMan]

Re: 3 questions about winterizing a 3.0 Mercruiser

Length of time required for freezing is really the question you want to know and is tough to say for sure (I assume you know water freezes at 32F). An hour or two at 32 degrees is probably not enough to cause any damage, but I would be concerned about anything more than that.. In fact, if you go through the calculations, you would probably need at least 24 hours of 30 degree weather for it to freeze, but who the hell wants to calculate that... If you are not ready to put it away for the winter, put some type of heating element in the engine compartment to keep it just warm enough not to freeze.

On my 3.0L there is one plug on the block on the port side and one on the exhaust manifold slightly aft of the block plug. That should be enough to drain the water out of the critical engine components. You should also drain the power steering cooler if you have one and it is recommended that you pull the lower end of the circulating hose (the big one on the front of the engine).

If you dry start it, you will burn up the impeller in the outdrive, and there is no gauruntee that you will get all of the water out.. you could try it, but its just easier to pull the plugs, especially on a 3.0L..

On a different note, never heard of a 3.0L in a pontoon.. Is the engine set down in a compartment beneath the main deck? And how does the outdrive bolt up?

 

[pontooner]

Re: 3 questions about winterizing a 3.0 Mercruiser

Thanks Imported

On a different note, never heard of a 3.0L in a pontoon.. Is the engine set down in a compartment beneath the main deck? And how does the outdrive bolt up?

Yes the engine is in a compartment below the main deck. It is also below the sun deck lid, which makes it real fun to work on (standing on my head and all). The compartment is made out of heavy gage aluminum and the outdrive is hooked onto the back of it just like it would be on a fiberglass boat.

I don't believe this is uncommon, but outboards are way more popular. I am fairly sure I get quite a bit better fuel mileage compared to same HP outboard.

 

[heyttown]

Re: 3 questions about winterizing a 3.0 Mercruiser

I have a 97 3.0 mercruiser... The previous post hit it right on with the drain plugs... I have a blue Plastic wing nut type plug on the block, screws in and out by hand..Very east, the exhaust manifold I think is a brass 7/16 plug, not bad either to reach.Its on the underside of the mani. The power steering cooler is a pain to reach on my boat so I just disconnect the line that comes from the cooler to my tstat, blow the water out then pour AF down it until it comes out the drive instead of reaching way back where my cooler is located....

Check out this thread, I had the same questions you had... And also posted some pics that may help you along.

http://forums.iboats.com/showthread.php?t=224473