Winterizing Drain Plugs

[62cruiserinc]

I am going to winterize my MCM 260 Mercruiser for the first time.

I see the two drains on the block (one on each side).

The manifolds each have 3 small (1/8" NPT?) drain plugs at the bottom. There are also 2 or 3 large (3/4" NPT?) plugs in the middle of one of the manifolds. Do these have to be removed for drainage or are they extra tap-offs for something else?

The risers (located at the end of the manifold) only have these large plugs in the middle and one of the risers has a smaller plug (3/8" NPT?) at one end. Do the risers have to be drained also or do they automatically drain into the manifold and exhaust?

My boat also has a water heater that works on electric or on engine heat with hoses attached to the engine cooling system. I traced these hoses and they are connected in series with the power steering cooler. Will these drain by gravity or do I need to use compressed air/ wet vac to get the water out?

Thanks
Steve

 

[alldodge]

With all those plugs I'm going to need a pic of the exhaust. The hot water heater should not run inline with power steering cooler (need pic), don't see anyway to heat the water.

 

[wellcraft-classic210]

Pretty sure you only need to remove QTY 2 1/4 NPT threaded pugs on the manifolds and also the QTY 2 1/4 NPT threaded pugs on the block. As you might expect these are at their lowest points. As ALLDodge has indicated pics will help provide a solid answer.

ALSO PRETTY SURE The power steering cooler should be plumbed into the inlet water coming from the impeller -- And that needs to be drained or back flushed with anti freeze. ( You may want to retrace your line to sure that's not the case and send pics if its not as some work may need to be done )


The Hot water heater needs to be drained as well -- I like opening both lines using compressed air -- But the experts may have other options for you as well.

 

[Bondo]

I am going to winterize my MCM 260 Mercruiser for the first time.

I see the two drains on the block (one on each side).

Ayuh,.... Remove both of them, 'n poke the holes free of debris,...
Also pull the Big hose off the circulatin' water pump,...

The manifolds each have 3 small (1/8" NPT?) drain plugs at the bottom. There are also 2 or 3 large (3/4" NPT?) plugs in the middle of one of the manifolds. Do these have to be removed for drainage or are they extra tap-offs for something else?

Most log type manifolds have 1 drain, but if ya got 3, pull 'em, 'n poke the holes clear of debris,....
The larger square drive plugs are castin' holes used in the castin' process, 'n don't need to come out, ever,....

The risers (located at the end of the manifold) only have these large plugs in the middle and one of the risers has a smaller plug (3/8" NPT?) at one end. Do the risers have to be drained also or do they automatically drain into the manifold and exhaust?

Same as the manifolds, pull, 'n prod the tiny plugs, leave the big ones alone,....

My boat also has a water heater that works on electric or on engine heat with hoses attached to the engine cooling system. I traced these hoses and they are connected in series with the power steering cooler. Will these drain by gravity or do I need to use compressed air/ wet vac to get the water out?

Yes, that All needs drainin', however you can do it,...
'n as AD says, the heater should be fed Hot water, from the intake manifold, not cold water from the P/S cooler,....

 

[crazy charlie]

Buy a 5gal Camco kit if you have an outdrive.Pull the stat and run 5 gals if AF thru the entire system.This will also do the however heater.Done this for the past 20 years and swear by it.Never an issue.Post back if you want detailed instructions using this kit and fogging at the same time.Charlie

 

[62cruiserinc]

Thanks guys.

I pulled all the plugs and let everything drain. I removed the thermostat from the housing. Then I used a shop vac on blower setting to blow out any water that was left ( there was some). Disconnected the heater hoses from the water heater and drained them. I poured AF into the open thermostat housing until it came out the block drain petcocks and then closed the drains. I reinstalled the manifold and riser drains and poured the AF into the thermostat housing. Will the housing fill up with AF or will it start going out the exhaust first? I poured 3 gallons and it still wasn't coming out the heater hoses or filling the thermostat housing.

BTW, I was wrong earlier, the water heater hoses are connected to the engine (manifold and water pump), not the PS cooler area.

We are getting a big freeze in a few days and I am working long hours at work so I only had evening hours in the dark (with lighting). I won't be able to run the engine, so how can I fog it without running it? Do I need to fog it?

Steve

 

[alldodge]

Opinion:
Fogging is good to do but will not hurt if you don't do it. Having a bit of oil on everything for the winter is nice, but the issue will always be it won't get to or stay on everything

The AF might start going our the exhaust but probably not, the risers are higher then the housing. It might start coming out the manifold drains if left open

 

[wellcraft-classic210]

Sounds like your making good progress !!!!

If you have not already done so -- You want to be sure to pour some antifreeze through your power steering cooler hose or drain it as it can trap water and get damaged in a freeze.

Next year you may want to fog BEFORE you drain the engine as its risky to run it with no coolant. ( But as AD said its an optional step )

 

[62cruiserinc]

Finished the winterizing last night.

I poured in AF until it filled the thermostat housing (4 gallons).

I also winterized the water system (tank, water heater and lines to sinks)

My power steering cooler doesn't have any separate hoses with water in them. The intake line from the outdrive has a steel section (about 6" long) in the middle of the hose that the power steering hydraulic lines attach to. Sort of like a auto trans cooler in a car radiator.

Steve

 

[62cruiserinc]

Forgot to mention that I also removed the outdrive and going to store it in my heated workshop.

I bought a HF motorcycle jack and converted it to an outdrive holder/dolly.

Steve

 

[wellcraft-classic210]

Steve
FYI -- The power steering coolers have a low spot that traps water -- Flushing the water inlet hose with Anti Freeze from the engine side will force the water back and out though the drive or in your case the water inlet. I have now seen several leek on spring start up when overlooked.

 

[Lou C]

Good point, I always disconnect that raw water intake hose from the transom, that is in line with the P/S cooler and point it down in the bilge to drain it. Then put the drive down all the way and fill the that hose with -100 marine AF till it runs out the water intakes of the outdrive or in this case the water inlet in the transom mount. This will push out the water and eliminate a freeze risk. My P/S cooler has a drain plug on it but there is a high likelihood that you would drop it into an inaccessible area of the bilge as its tough to get at. Since I changed the OE batwing style exhaust on my old OMC to a center riser set up it is easier to get at by far because the old exhaust manifolds kind of wrapped around the rear of the engine (to save space I guess) but I still do it the same way. Easier and always works, I've had temps down to zero and have never had the P/S cooler freeze up.

 

[62cruiserinc]

I disconnected the inlet hose at the PS cooler, blew air into the thermostat housing to blow the water out of the cooler, and then poured the AF into the thermostat housing until it ran out the cooler. I then plugged the open end of the cooler and added AF into the thermostat housing until the housing was full. Finally, I blew air into the intake hose going to the transom untill any water in the hose blew out the hole at the now-removed outdrive.

Thanks to everyone for the help and suggestions.

Steve