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WINTERIZING YOUR INBOARD
First things first, let's get those gas tanks filled and
fuel stabilizer added according to the directions for
storage (OMC brand is called 2+4). We want them full to
prevent condensation, and we add stabilizer because today's
fuels can have a shelf life of only 3 months without it.
Next, run the engines up to operating temperature to get the
stabilizer into the entire fuel system, and to warm the
engine oil. Next, let's change the oil and filter. The
reason we want to do this before extended storage, is that
the used oil has accumulated acids which can attack internal
engine parts over the storage period (while I am a tad
skeptical over this issue, I'm not about to question an
engineer's advice). Warming the oil makes it easier to
change and suspends the sludge resulting in a cleaner
change. Since you're gonna change your oil anyway, we might
as well do it now. Don't forget to replace the filter and
don't scrimp on the quality. A couple of bucks saved is
hardly worth the effort when you look at what you're
Your engine is equipped with a special fitting
for getting the oil out via the dip stick tube with a
special pump (attachable to an electric drill and available
at your dealer). The fitting you attach it to looks just
like an garden hose end (which is exactly what will fit onto
it). On Mercruiser, the dipstick and drain tube are one and
the same. On OMC's, we made some models the same as Merc,
and some with a second tube and cap specifically for
draining the oil. Since writing this 15 years ago, things have
changed so please consult your owner's manual for how to pull
the engine oil for your engine.
Either way, the oil cannot be changed
without some sort of suction pump and proper fittings as
there is no drain plug in the oil pan (like you would want
to drain your oil there anyway ). Prior to about 1976,
neither manufacturer had what I just described, and we have
to use a glorified straw that went down the dip stick tube
which always leaves you with the uneasy feeling that you
didn't get it all (since it's difficult to tell whether or
not the straw is at the bottom of the pan or curling around
and coming back up again). On these older models (not
applicable to most) there *is* a drain plug and if you get a
heavy duty garbage bag, you can drain the oil into the bag
and *carefully* remove it from the bilge. It's surprising
how the tiniest hose clamp sticking out will easily tear
open your bag of oil sending it into your bilge .
Refill your engine with the oil the manufacturuer reccommends.
OMC Cobras take SAE 30 weight oil for us
Northerners, and those in the warmer climates should
consider SAE 40. Mercury reccommends a 25W40 but BEWARE this
as this is NOT car oil - it's a blecnd of 2 differenbt types of oils
with anti-foaming agents specifically designed for the environment
they operate in. If you use car oil you rish engine damage. You have been warned.
No debate on what oil to use
please -- read your manual and use what it says.
not scrimp on quality in this area -- think of how important
the job oil must do and how little difference there is in
price between the good stuff and the cheap. I use name brand OEM oil
in all the engine brands we store. Don't
forget to start the engine and get the filter full again
before checking the level (the engine should sit for a full
minute after shut-off before taking the reading off the
Fogging the engine..............
First, pull the flame arrester (breather), restart the
engine and pour or spray in a storage fogging oil (OMC calls
it just that). Not knowing what some instructions might say
on some brands of fogging oil, you should do the following:
Raise the idle to about 1500 RPM and begin spraying in the
storage fogging oil in sufficient quantity to slow the
engine to about 1000 RPM. This
ensures you will get in as much oil without loading and
stalling the engine in the process. If you think you're doing
the engine good by dumping oil in to stall the engine, think again.
This can cause something called hydro locking and can split a cylinder,
break a piston or bend a rod. Seen it, fixed it, lectured endelssly
So what's this stuff do?
It coats the intake, valves, pistons and cylinders to
prevent rust and corrosion from taking their toll over the
storage period. It's an absolute must if you want to keep
your engine from seizing, especially if you plan on leaving
it moth-balled for a long period
After you have a good white smoke pouring out of
the exhaust (and have injected about 8 to 10 ounces of
fogging oil), simply grab the choke plates and close them
manually to stall the engine (or simply have someone shut
the key off). The reason for using the choke is that you can
continue adding fogging oil while you do it. If you use the
key, by the time you get out of the bilge and up to the
dash, the engine will have cleared a lot of the fogging oil.
Now it's time to get the boat out of the water (unless
you've already got it out and were using a flushing
attachment to get this far).
Changing lower unit oil..........
Let's start by lowering the drive(s) and draining the
gearcase oil into a suitable container. Since we're trying
to cover all the bases, here's at look at what we should be
draining and where to find the screws on all brands (I'm not
up on the newest Merc's, so those in the know feel free to
correct or add to the post and I'll incorporate it for next
time). BTW, if the oil is at all creamy or milky, get thee
to a dealer or post back your troubles and I'll see what I
can do to help.
1. OMC Stringer mount stern drives -- pre 1976 (the one with
the big rubber boot in the transom): There are two
reservoirs to drain -- the upper gearcase, and the lower
gearcase (each is independent of the other). The upper is
drained by a screw on the starboard side of the upper
housing, and a dip stick in the top center. The lower
gearcase is drained by a screw near the leading edge of the
*bullet* and also one just above the anti-ventilation plate.
Always fill from the bottom hole until it comes out the top
one (or up to the proper level on the dipstick). New screw
gaskets are strongly recommended for ALL screws.
2. OMC Stringer mount stern drives -- post 1976 (still the
one with the big rubber boot in the transom): #1 above
applies, but there are two more reservoirs that previously
weren't drainable without disassembly. The first is the tilt
clutch (the thing with the tilt gear sticking out of it) and
the drain screw is located right on the bottom with a
vent/level screw on the side about 2/3 up.
reservoir is a little tougher to find as it is within the
intermediate housing that connects to the bell housing on
the engine. The drain is accessed from the outside of the
boat on the starboard side of the unit. It is located where
the shaft runs through to the engine and looks just like all
the others. The vent/level screw is located at the top of
the intermediate housing and is easy to spot as it is much
larger than all the other screws. Same filling procedure for
these two reservoirs -- from the bottom up.
3. OMC Cobra 1986-1993 There is only one reservoir (the upper and
lower gearcase share oil). There are, however, three screws.
The drain screw is located in the *bullet* at the bottom,
and the vent screws are located midway above the
anti-ventilation plate and at the top center in the form of
a dipstick. Pull the top and bottom screw to drain, but
refilling requires that you install the bottom screw first,
then fill the entire drive from the middle screw only until
you get the proper reading on the top dipstick.
** FAILURE TO
FOLLOW THIS FILL PROCEDURE WILL MOST CERTAINLY RESULT IN
UPPER GEAR FAILURE. **
If the unit is filled incorrectly, an
air pocket will form inside the drive such that when it
*burps* up at a later date, will result in the upper oil
level dropping thus destroying the top gears. Trust me on
this as I have made quite a bit of money on people who were
unaware of this procedure (they now leave their boat in my
care ). Again, new gaskets are advisable on the screws.
4. Older Mercruiser (MCM Ia, Ib and early Ic's): Same as #1
above (two reservoirs) -- one upper and one lower gearcase.
Only difference is that the upper gearcase has top screw on
the side and you fill it until it runs out there.
5. Most other Mercruisers (later Ic's, I, II, & Alphas):
Common reservoir throughout with only a lower screw on the
bullet and one at Same as #3 (Cobra) except that you don't
have to worry about the air pocket problem and the top screw
is at the side. Simply fill from the bottom until it comes
out the middle, plug the middle, then continue filling from
the bottom until it comes out the top.
6. Mercruiser Bravo (four models now I believe -- the Bravo
I, II, III and the BlackHawk): Same as 5. except the drain
the Bravo I is accessed by removing the prop -- it's at the
bottom of the exhaust housing.
7. Volvo 280/290 (white): One reservoir , one bottom screw
and one top (dipstick like OMC).
8. Volvo/Cobra SX 1994 and up (grey): Same as 3. (Cobra and
Volvo manufacture this drive together)
So what lower oil should we use?
On OMC electric shift models, you MUST use something called
Type C (now called Premium Blend) in the lower unit only
(absolutely no substitutes allowed, period). All other OMC
reservoirs and models should be filled with Hi-Vis or the
new Ultra-HPF synthetic. For Mercruiser use OMC Hi-Vis,
Ultra-HPF, or Quicksilver Gearlube (or their synthetic
blend called High Performance Gear Lube). Volvo 280/290 originally called for SAE 30, but I
strongly recommend moving to Hi-Vis or better yet Ultra-HPF.
Volvo SX and Cobras use Ultra-HPF Synthetic.
My advice is to use
Synthetic gear oils whenever possible. Actually, my stronger
advise is to RTFM and see what it calls for -- I have seen
engineering reports which shows gear and bearing wear is
reduced up to 50% over conventional oil, and it does not
break down under stress and heat like conventional oils. As
for getting the stuff in, all manufacturers offer an
inexpensive plastic pump which fits into the oil bottle.
Count on using at least 70 ounces to completely fill any
Annual drive maintenance....
While we're talking about drives, now's the time to pull it
and grease the U-joints (OMC stringer mounts do not have
them, so ignore this if you own one). First of all, this is
a two person job for the inexperienced. In fact, I don't
think this should be attempted the first time without
someone present who has done it before:
On Cobra drives, remove the six mounting bolts and rear trim
cylinder retaining shaft, the pull on the drive (careful,
they're heavy! ) The grease nipples may have to be turned
to 45 degree angles to get the grease gun on it. Use this
opportunity to grease the gimbal bearing as well so you can
see when it is filled. The nipple is located near the
transom on the starboard side of the transom bracket.
the splines of the *donkey dick* with OMC molly lube, and
oil the shaft, o-rings, and outer diameter of the U-joints
with oil to aid re-installation. Place a new gasket on the
studs, and re-install the drive using a large screwdriver
jammed into the U-joints to turn the shaft back and forth to
get through the bellows and align the shaft.
All of this
will be very clear when you have the drive off. If you're at
all uneasy, a dealer will probably charge $30 to do it and
may let you watch (I do). In fact, I will have the customer
help if he likes so he can learn. Pulling the drive now on
an OMC may also save some aggravation later. If the gasket
hasn't sealed perfectly (and the early ones often didn't)
the shift linkage pocket fills with water.
While the gaskets
seems poor at keeping water out, it seems to do a good job
of keeping it in and if this freezes, you'll get a nasty
(albeit cosmetic) crack in the side of your drive. Pulling
the drive automatically drains this pocket. If you're not
going to pull the drive, you merely have to loosen it for
this pocket to drain. Newer models incorporated a drain plug
at this spot, but since I recommend pulling the drive to do
the u-joints anyway, we won't have to worry about it.
On most Mercruiser drives, the same applies as above (including
greasing the gimbal bearing) except the drive MUST BE IN
FORWARD GEAR. Failure to put the drive in forward will not
only make it tough to remove, but shift parts WILL BE
DAMAGED if you succeed. For re-assembly, make sure the drive
is in forward and use the prop to help align the splined
shaft into the engine coupler. If you've got a Bravo drive,
the shift requires a special release procedure and many of
the new Merc's have sealed u-joints so unless you want to
check bellows integrity, no need to be in here anyway. MAKE
sure that the quad ring (4 sided circular ring, like an
replaced and properly glued into place EACH time the drive
Merc makes 3 different "Kits" for this purpose,
MCM "I" drives thru 1984 (PRE Alpha drives) 27-64818A1 and
27-94996A1 for Alpha and The Second Generation Alpha (AKA
GEN II) uses a different gasket due to the remote gear lube
bottle. I will get that # if anyone is interested, just
have don't have it on hand at the moment.
On Volvo 280/290 drives, the U-joints are sealed and even if
you wanted to get in there to check them, it's not for the
back-yard mechanic. Leave this one to the pros.
All brands should have their bellows changed at least every
five years. I've got plenty running on their original at
twenty years old, and just replaced one the other day that
failed after three years. Bellows replacement is not for the
faint of heart so unless you have at least a basic idea of
what to do, leave this to the pros. It's also harder to do
in the cold so let's talk about it next spring when it's
nice, but still early to boat. :-)
As for impellers, one year, five years, ten years whatever.
I've plenty still running on the originals, but I know there
are plenty of maintenance freaks in here who like to do it
annually. Whatever turns your crank. :-)
Back to the engine....
So what anti-freeze should we use? Technically, if an engine
is drained properly, you don't need *any* anti-freeze (which
is why you won't see it in the service manuals). Personally,
I like to get anti-freeze in there to mix with any water
that may have been missed, and to provide the inside of the
block with protection from corrosion. Also, I use regular
toxic ethylene glycol anti-freeze (mixed 50-50 with water)
because it's just plain better at protecting your engine.
do not, however, allow my stored engines out in the spring
without removing it first and recycling it for use again
next year. If you're just gonna start your engine next
spring without removing the anti-freeze, obviously you
should use propylene based non-toxic anti-freeze.
you do, bear in mind that while it may be non-toxic ,
(‘less' toxic actually) IT IS STILL ILLEGAL to dump foreign
substances in the water, whether it is toxic or not. I do
not tolerate such actions at my ramp and have little respect
for anyone who does. If you've been guilty of such practices
in the past, you know better now and should change your
ways. Think about how irresponsible people are ruining it
for all of us and if you see someone else doing it, report
If you choose non-toxic anti-freeze, DO
NOT USE PLUMBING ANTI-FREEZE. It attacks the rubber seals in
the engine water pump and since it already comes ready to
use it raises a raises a further concern -- What happens if
it meets and mixes with a water pocket? It's possible the
solution will be significantly weakened in this area of the
block which may not provide the proper protection needed.
Food for thought. An interesting side bar — even if you use
non-toxic in the fall, it will BECOME toxic over the storage
period due to migration of the nasties they're making those
marine gaskets out of nowadays. I therefore repeat myself -
get the stuff out before starting in the lake - it's toxic
as hell anyway you look at it.
Time to get that water out of your engine so let's locate
your drain cocks. As a GUIDE line, here's where to look:
4 & 6 cylinder in-line engines: one drain on the block, one
on the manifold
(usually on the port side).
6 & 8 cylinder V-block engines: two drains (on each side of
the engine) and
one on each manifold (sometimes this is simply a bigger
rubber cap and hose
Older Mercs (shudder) had a multitude of hoses and
drains (the 888 causes me to cringe).
These drains are usually brass cocks, but sometimes they are
just threaded brass plugs (and are sometimes painted thus
making them difficult to see). Always remove the whole thing
(even if loosening appears to get the water flowing). There
is a tremendous amount of rust and corrosion laying behind
them and you must ensure that the way is clear for them to
I shouldn't have to remind you what will happen if you
don't. The next part gets a little tricky because of the
number of variations out there, so I'm going to stick with
the basics and anyone with something different can post back
and I'll offer advice on an as needed basis.
*Most* modern engines have a main line running from the
water pump in the lower unit up to the thermostat housing.
Find this hose first and remove it from the thermostat
NOTE: There is absolutely no need to remove the thermostat
housing to winterize your motor. The guy who told you this
doesn't know what he's talking about. Are we clear on this?
Using a funnel, pour anti-freeze into this hose and keep
going until anti-freeze comes out the water pick-up in the
lower unit. The anti-freeze will not only push the water
out, but it will also
flush the power steering cooler (located in-line of this
hose) and the water pump thus we kill three birds with one
stone. Now there's no need to locate and attempt to undo
the little plug on the collar -- trust me.
Next, remove the
two hoses running to each exhaust manifold at the thermostat
housing. Pour anti-freeze into the hose until it comes out
the manifold drain cock, then install & tighten the drain
cock. Continue to fill the manifold with anti-freeze until
it comes out the prop. Repeat this procedure for each
Next, pull the large diameter hose from the
thermostat housing (that connects to the engine water pump).
Begin filling this with anti-freeze until it starts coming
out the drain cocks. Install and tighten the cocks and
continue filling until the block is full. Reconnect all
hoses and tighten clamps. Anyone who has more hoses or isn't
clear on what I've said, please post back and ask for a
clarification as I will continually update this post for
future release. Newer Volvos, some Mercs, and all straight
shaft inboards have an engine mounted water pump. The smart
people reading this will be able to apply what I've already
posted to their situation. If dumb ones should ask
themselves why they're attempting to screw with a very
expensive part of their boat to save a few bucks.
First, let your taps run to drain the main holding tank
(don't forget to shut off power to the hot water heater).
Next, drain the hot water tank (small drain cock at the
bottom and lever vent at the top). Remove both water lines
from the tank and devise a method of connecting them
together (using an elbow from the tank etc). The reason for
this will become clear later.
Now go to your pressure pump and holding tank (they will be
close together). If possible, remove the line that runs from
the tank to the pump (at the tank end). If the line is long
enough, merely redirect the line into a jug (or pot, or
bowl) of plumbing anti-freeze. If it's not long enough, find
a way of making it so. Turn on the power to the pump and
open only one cold water
tap until the system primes itself. Allow it to run until
anti-freeze comes out the tap. Shut off the tap and turn on
the hot water tap until anti-freeze appears (this will take
slightly longer as the path is usually longer). Repeat this
procedure for every tap (hot and cold done separately)
and shower (and the toilet if it's part of the pressure
Don't forget about the ice maker in the fridge, the
sink in the v-birth, or the shower or external tap on the
stern of the boat. Make sure you keep your anti-freeze
supply above the hose end to prevent you having to reprime
the system. When you're done, turn the pump off and
reconnect the line from the pump to
the tank -- job done (leave the hot water tank by-passed
Now you're probably asking why we haven't put
any anti-freeze in the hot water tank or the main water tank
and the answer is simple -- we don't have to. Both tanks are
sufficiently drained such that they will not incur any
freezing damage, and by not filling them with anti-freeze,
we don't have to worry about tasting the stuff for the first
month(s) next year. Non-toxic or not, the stuff tastes and
smells awful. To start the system up in the spring, merely
fill the water tank with fresh water, open all taps one at a
time to clear the anti-freeze, then hook up the hot water
tank hoses again.
system is completely purged of all anti-freeze ensuring no
lingering smell or aftertaste. This method is not only
quick, it's also the best way (by far) to winterize your
plumbing. Stay away from marinas who merely pour gallons and
gallons of anti-freeze into your holding tank. Not only will
it get diluted by any leftover water (and thus not
adequately protect) but the taste
will linger forever in your water. My method will use less
than 8 liters (2 gallons), where some marinas will use up to
a case (or two) under their method.
Since the toilet is usually supplied from a sea cock (erotic
sounding, eh?) in the hull, we must find and access it. Once
found, undo the hose clamp and pull off the hose. If you're
still in the water, don't forget to close the seacock.
Place the hose in the anti-freeze jug (engine anti-freeze
works fine here and is cheaper to use). Go to the toilet and
operate the pump until you have sucked out all the
anti-freeze out of the jug and passed it to the holding tank
(which you hopefully had pumped out while it was still at
the marina). Reconnect the hose and you're done (leaving the
sea cock closed if you're in the water, open if you're not).
The floor is yours Peggy if you'd like to add more here.
I strongly recommend the batteries be removed entirely from
the boat, but if you're one of those types who leaves them
in, at least disconnect them (ALL CABLES). Turning the
battery switch off is not good enough. Next, clean the
terminals and tops of the batteries as any moisture or dirt
will allow cross discharge between the posts. The batteries
should be stored in a cool, dry place. Warm humid storage
will promote cross discharge through the air. Charge the
batteries at least every two months. Watch your water levels
and top up as necessary.
FYI, I store over 250 batteries in an outdoor building
(unheated). I ensure the batteries are fully charged prior
to storage, and charge them only once in January. I have yet
to lose a battery over the winter and have had some last up
to 9 years before I gave it the boot. A good battery will
give a least five full years of service. One more thing to
try and kill an urban legend: storing your battery on a
concrete floor will not hurt your battery, PERIOD.
I'm gonna leave this up to you guys to yack about because
it's more of a regional thing. Where I live, the water is
clear and the algae growth minimal (God's country). We don't
even bother cleaning the boats until spring, and even then,
a good scrubbing and spray brings them back to nearly new.
will recommend hydrochloric (muriatic) acid for those
stubborn stains and water lines, but be careful -- that
stuff is mighty toxic to the lungs and corrosive to skin.
Apply it with a paint tray and roller, let stand for 10
minutes, then rinse off. Water will quickly neutralize the
acid. Don't forget to store your boat bow high and remove
all drain plugs. It would be a shame if you found a split
hull in the spring (well, not for me and my fellow marina
If possible, store your tops in a warm place at home. While
the new synthetics are quite durable, the older vinyls and
viewtex (clear plastic) don't like the cold. Obviously, a
good wash and rinse is recommended before storage. If the
boat is going to be outside, it's not that tough (or
expensive) to build a wooden frame (using the tent pole
method with bailing twine to support). A suitable sized tarp
is the best investment you can make and it can last for
years if properly tied when on (to prevent flapping in the
wind) and properly stored during the summer. Shrink wrapping
is expensive, and not reusable.
Have I missed anything?
Now, about your bill...............
Brown's Marina Ltd.
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Brown's Marina Ltd.
1641 Chaffey's Lock Road
Elgin, Ontario, K0G 1E0 CANADA
Tel: 1-800-561-3137 (toll free)
Tel: 1-613-359-5466 - Fax: 1-613-359-6376
Comments: send me email: firstname.lastname@example.org