Winterize

[Dan Currie]

I have a 1975 Merc 140 HP.
Need to winterize.
What do I do?
Is this something I can do myself?

[KnottyBuoyz]

My buddy tried that last fall. Didn't get it quite right. Cracked block, storm hit, boat sunk. $13K repair bill. Thank gawd for insurance.

Do a quick google search on winterizing a mercury inboard outboard and you'll get plenty of advice.

Yes it is easy to do yourself if you have the time and a few basic tools. What I did was pay a marine mechanic to do mine the first year and watched him very closely. I've never had a problem. My buddy, well that's something you want to try to avoild.

[Slider]

Originally Posted by Dan Currie

I have a 1975 Merc 140 HP.
Need to winterize.
What do I do?
Is this something I can do myself?

I do my 1974 140 I/O myself....I pull the lower hose ( looped off the water pump) by undoing the lower hose clamp , open the tap just in front of the thermostate housing and drain the 2 plugs and open block tap on the right side as you face the engine rearwards ( port side ) .

I leave them all open and have never had a problem in an area that can reach as low as minus 40 cel / fahr deg's

It is hard to describe were these threaded plugs and tap are without a diagram .The plugs and tap are noted in the original owner manual that came with the boat or go buy a shop manual (Seloc) from a marine shop such as West Marine..

P.S. drain and replace your lower unit gear lube as well to make sure no water is in the lower unit....

If you can't find the diagram....email me and I will scan and send you the page from the manual showing the drains etc.

[Dan Currie]

Thank you!
Great advise, I'll get a manual.

[jflongwell]

Fairly easy to do.
Use the "ears" on the outdrive to provide water to the engine. Start and warm up, then spray fogging oil into the carb. The engine will stumble and run rough, but keep spraying. After about 10-15 seconds, turn the engine off.
The block has one drain as does the exhaust manifold, open both. I usually did it hot. I also pulled the spark plugs and sprayed fogging oil into the cylinders and rolled the engine over a few times with the plugs out.
Another method is to put the outdrive in a container with 2-3 gals. of winterizing fluid (not glycol!) and purge the water out by running the engine until the fluid is gone. This prevents corrosion of the inner passages. I never did this.

[TerryKing]

I'm from Vermont; cold Winters. I have been 'Winterizing' my GM V8 boat engine, and many mowers, snowblowers (Summerizing!) etc. for many years. I agree with previous post about what I call 'Oiling Down'.

(This got expanded, like my wife would characterize my conversation )

I think there are always three parts of Winterizing:

1. Fuel System: Run stabilized gasoline mixture (I use "Stabil") for a few minutes at least, or ideally in the last 1/4 tankful on engine, so fuel lines, pumps, carburetors, injectors get treated against gumming and corrosion. After last run, drain fuel, blow out lines, drain carburetor (you can sometime remove a lower bolt to drain)..

2. Cooling system: If a boat, drain carefully and according to manual if available. If necessary, purge water with antifreeze if complete draining is not possible (my Vee Drive for example..) Remove pump impeller if possible to keep from months-long shape set. Double-check antifreeze if a regular closed cooling system on car or boat, with an Anti-Freeze tester.

3. Protect internal engine surfaces from condensation and corrosion: Run engine for 30 seconds or so after draining cooling system (or drain afterward if cooling 'ears' or fitting is available). I make a mixture of 40% gasoline, 40% automatic transmission fluid and 10% "Stabil" gasoline preservative. Run engine at high idle and drizzle 2 or 3 ounces (V8) of the mixture down the carburetor / intake. The engine will run rough. Don't drown it for 15 seconds or so, until the exhaust is really smoky. Increase the flow until really rough, then drown it enough to stall. With this, I see really oily plugs and exhaust manifold, without pulling every plug and adding oil.

I've been doing this for 30 years on my boat engine. I usually remove and clean plugs in the Spring, and crank it with ignition off until I get 30 PSI oil pressure, then install the plugs and it fires immediately with a short smoky exhaust, but no sign of corrosion.

Small mower etc. engines also start right up next season without the gummy carburetors and stuck valves I see others have.

Recently I've been living overseas in Africa and China during the (USA) Winter and I've 'winterized' my trucks this way and had them wake up happy in June.

I hadn't though about it for 50 years, but I'm pretty sure I saw my Dad do this on the lawn mower long ago!