winterized my 91 3.0L mercruiser

[beretta96]

Hi guys,

I'm new to this forum as a member, but have been here often to read up. I must say I've learnt alot. Last year I bought a 91 Invader 18' bowrider with the 3.0L mercruiser alpha 1 drive.

From this site, I learned how to change my own bellows this spring. Now I've just winterized it myself for the first time. I did take a few tips from a couple of guys at work who use this on their I/O's.

I stabilized the fuel, added an octane booster, changed the fuel/water seperator (which I installed as well). With muffs on, I ran the boat at 1500 rpm for about 10 or 12 minutes. I was told to do this to open the T-stat. I then had a pail with a hose plumbed in the bottom, installed muffs again, filled it with 4 gallons of -50C antifreeze with corrosion inhibitors. Placed the pail on the swim platform, then started the boat and when the antifreeze was almost gone, I then fogged it until stall. Then I pulled the plugs and sprayed some fog oil into the cylinders.

I've read on this forum that this way probably won't work and may still crack a block.

Has anyone else tried it this way? I believe 4 gallons was enough since the discharge was pink for about 2 minutes. I just wondered if I should have used say 6 gallons.

My next step was to remove the outdrive and put it in the basement for the winter so I can change the water pump. I'm going to get an aluminum plate made to the gasket template with a hole for the shifter to stick out. This way nothing will get into the opening.

All your opinions are appreciated,

Thank you,

 

[JustJason]

Re: winterized my 91 3.0L mercruiser

The bucket trick only works 50/50.....

You really need to be draining all the water out of the block via the drains. Then pulling your hoses and pouring antifreeze in that way.
Your probably better off storing the block completely drained then using the bucket.



What are ya talking about with the shifter and this aluminum plate thingie??

 

[Alumarine]

Re: winterized my 91 3.0L mercruiser

Hello and welcome. I'm not an expert but I'm sure someone will come along and offer better advice.

But, I think you've answered your own question.
"I believe 4 gallons was enough since the discharge was pink for about 2 minutes. I just wondered if I should have used say 6 gallons."

If you're not sure if it's going to work why not just open and clear out the drain plugs? That way, you won't have to worry if you used enough antifreeze.

- edit - looks like I got beat to the punch

 

[beretta96]

Re: winterized my 91 3.0L mercruiser

My concern with not pulling the plugs, is I'm not sure how many there are, and where they are and if they're seized and I mess up the threads. I'm also afraid of missing one and cracking something so I figured even if there was a hint of water somewhere, then at least with the -50C stuff it may dilute down to say -30C if that makes any sense to you guys. I called 2 local dealers to ask for help, but they want me to bring it in for 2 hours labor + material.

Since I took my outdrive off for the winters, I'm having a blank aluminum plate made with the 6 bolt holes to fit where the outdrive would bolt to. The shifter end is longer so I was going to have them cut the hole for it so the plate would sit up against the old gasket. I'm doing this just to keep the elements out until spring.

 

[HT32BSX115]

Re: winterized my 91 3.0L mercruiser

Howdy,

If you use a tub and let the drive draw (with a hose and muffs) AF into the engine and position the tub to catch most of what comes out, AND let it run until the T-stat is open, there's no doubt in my mind that you'll have AF everywhere it needs to be.

The problem of using AF by pouring it into a coolant hose with the engine off or even removing the T-stat housing and pouring it into the engine is that it doesn't mix well by just pouring it into the engine anywhere.

By drawing it up into the engine while it's running and catching the discharge into the SAME tub you're drawing it from, you circulate it. If you do it long enough for the T-stat to open.....(it'll get hot....don't let it run while having lunch or you might overheat the engine!) it goes everywhere including the risers and elbows (where it will help do a little anti-corrosion action too) You also put AF in the raw pump, hoses, power steering and oil coolers (if installed) that don't always drain when you drain the block & manifold drains. On my Bravo, If I didn't do this I would have to remove the most difficult hose I have, to remove and drain the power steering and oil coolers.


Even though I have closed cooling now the raw water output from the Bravo raw pump still goes thru the same under engine hose (the most difficult one!) to the power steering and oil coolers before going to the heat exchanger (raw side)..... Because I draw AF into the raw side I still don't have to remove that hose, drain the heat exchanger, worry about my exhaust elbows which still do pool a little water due to how the raw water is routed from the heat exchanger to the elbows. (I have a FULL system)


If you're careful you can use the same AF year after year. (if it's the toxic type, don't leave it uncovered so any animals can get to it.....or don't use toxic type...)


Regards,


Rick

 

[JustJason]

Re: winterized my 91 3.0L mercruiser

The problem of using AF by pouring it into a coolant hose with the engine off or even removing the T-stat housing and pouring it into the engine is that it doesn't mix well by just pouring it into the engine anywhere.

That's why I drain the block first.... and i keep pouring antifreeze until it comes out of the drains. It doesn't have to mix in the engine if 95% of the water is out and your pouring in premix antifreeze. that last 5% of the water isn't going to hurt anything. and will certainly mix with whatever you pour into it.
The problem i have with the bucket is this. 90% (and i don't know the real number.... so i'm making that up, but it is the majority) of everything pumped by the waterpump goes straight out the manifolds. So even though your seeing what you think is an okay amount of antifreeze coming out of the exhaust, you really have no idea of what's in the block.
If you do it my way, you know exactly what's in the block, and exactly what's in the manifold. And you wastse less antifreeze.
I use nontox not just for animals. Its so when your ready in the spring you can fire it up in the driveway or in the lake and not have to worry about it going down sewer drains, killing your grass, or poisoning the lakes.

ps~ not 1 of my winterizations has ever come back with a cracked block.

 

[HT32BSX115]

Re: winterized my 91 3.0L mercruiser

The problem i have with the bucket is this. 90% (and i don't know the real number.... so i'm making that up, but it is the majority) of everything pumped by the waterpump goes straight out the manifolds.

Well, you're right if the T-stat is closed. If it's open then that AF will circulate in the block and if you run it long enough it'll all be the same mix (assuming you're catching it all and "sucking it all"!!

Either way is fine IMHO......

I'm sure glad I put closed cooling in mine though!!

 

[Lou C]

Re: winterized my 91 3.0L mercruiser

Like I said in the other winterizing post, I do exactly what Capn Jason does, drain, poke the holes with a screwdriver to make sure it really drained, start pouring AF till a little comes out the drain, (my touch here, put a little OMC triple guard grease on the drain plugs) then replace the plugs and fill up with
-100 AF.
In your case I'd find the drain plugs (simple on the 3.0) and remove then, drain a little into a paper cup and put it in the freezer, that way you can see if the AF was really strong enough. If not, just drain it all out and backfill.

 

[Joebklyn]

Re: winterized my 91 3.0L mercruiser

I intend to use a 1635 gal/hr electric pump and a new Wallymart tub and about 8 or 9 gallons of AF. Pump on, muffs on , start the engine on my 3.0L. Let it idle untill hot, thermostat is open hot AF is flowing. Spray the fogging oil in the carb until the engine stalls. Replace flame arrestor. Wrap openings on flame aresstor with duct tape. Change oil & filter. Change lower drive oil. Spray Mercruiser Engine spray all over the metal parts of the 3.0. ( avoiding belts) I then intend to remove each spark plug and spray a little fogging oil into each cylinder then replace plugs. Any unused AF goes right back in the jugs. Any thing wrong with my thinking here? just trying to save $278.00. Thanks Joe from New York

 

[chiefalen]

Re: winterized my 91 3.0L mercruiser

Removing the drive is never a bad thing. Merc is different than omc. Cant just pull 5-6 bolts and pull it off.

2 drain plugs on your setup, both port side, pull them and with a wire or screw driver poke in the hole to make sure all the rust and stuff in there comes out.

Remove long hose from t-stat and pour af down that hose 1/4 gallon maybe while you hold the hose up.

Pull the other hoses and pour af down those. Leave plugs out and your done.

If you leave the drive on as i do i make sure its all the way down. So water don't freeze in my pump.

Fogging is good, i personally don't.

I don't add nothing to the gas. I don't like sta-bil. And octane booster could hurt more than help.

All of the above is in my own inexpert opinion.

 

[Lou C]

Re: winterized my 91 3.0L mercruiser

Joe from Bklyn (grew up there myself) do it my way, it is easier and less stressful. You are less likely to burn up an impeller just running it on the water hose, warm it up good, change oil and filter, fog, drain, back fill with AF thru the hoses. If for some reason the pump can't get the AF (which is denser than water, remember) up the drive fast enough, the impeller might burn a bit and then you motor will start to overheat.

After the winterizing I do pull the drive off and check the bellows, gimble and ujoints. Cobra drive comes off easy after you remove 6 nuts and trim rams. Merc is similar. They are heavy so you may need to get help if you have a bad back. I built a stand for mine.

 

[JustJason]

Re: winterized my 91 3.0L mercruiser

I intend to use a 1635 gal/hr electric pump and a new Wallymart tub and about 8 or 9 gallons of AF.

wow that sounds like a pain, and an expense.

What cost more??? 9 gallons of antifreeze and some fancy pump, plus a tub. or 4 or 5 gallons and a screwdriver and maybe a plastic funnel?

Besides... even if you bought 10 gallons of antifreeze (the toxic stuff) and you mixed it with water, your going to have 20 gallons of mixture. Its not going to be enough water to fill a bone dry block (which you would want to do or else your mixture goes more towards the water side) with the lower unit in a bucket sucking up new water and exhausting the excess into the same tub. It's just not enought.
I mean test tanks from Kerr Marine and such are hundreds of gallons, and even a 3 liter heats up that tank fairly quickly.
Its a little extra work to pull the hoses, i know this. But part of the winterizing service is inspecting those hoses and clamps. Nobody wants a burst hose or blown clamp to happen on the water. And its not just the hoses either, take off your hoses sometimes and look at where they hook up on the tstat housing and manifolds, even the cast iron inlets get clogged up. Part of the service is inspecting those as well.

 

[Maclin]

Re: winterized my 91 3.0L mercruiser

I just drain everything and leave it dry. If you just try to get antifreeze mix circulated then you miss the chance to get the sand and junk out of the block and manifold water passages.

I have good access in my boat so it takes me less time to get the seats and engine cover out of the way, remove the block and manifold drain plugs and remove the sea water pump cover on the front of the engine (Volvo) than it takes to get a tub ready and pour $70 or $80 worth of antifreeze into it and wait for the engine to warm up and circulate it. I remove the thermostat housing and manifold hoses also and pour clean water in until I like how clear it is and how fast it is running out the drain holes. I leave the plugs out for a bit and tow the boat around some to jostle any remaining water around and coax it over to the holes. It is also no cost to me until the next season when I get a new thermostat housing gasket and tune it all up then anyway. I am an inland fresh lake trailer boater, no salt water, boat is never in the water for more than a day or two.

Just before winterizing I get the fuel treated (actually I treat my fuel at each fill) and run the boat at a good clip on the lake for a good amount of time, making sure the secondaries are opening up, to get as fresh of fuel as possible up into the carb for the long layup. This fall I plan to make a weekend of it out at the lake camping and change the oil right after that last run when it is good and warm. Then drain the water and put her to sleep.

 

[Indy200]

Re: winterized my 91 3.0L mercruiser

Has anyone ever tried blowing air into the hoses after draining? Might help to remove any water that has pooled in low spots?

 

[imported_TheMan]

Re: winterized my 91 3.0L mercruiser

Why do you think they added drain plugs? Use them.

I had an '89 merc 3.0. It had two drain plugs: 1 quick drain on the block (port side, slightly above oil pan) and 1 removable bolt on the exhaust manifold (underneath, 3/4 back). Takes less than 2 minuets to drain properly, doesn't cost anything, and gave me the satisfaction all winter long that there isn't any possibility of freeze cracks.