2001 GT40 - Remove RWP when winterising?

Leave the RWP in place.

Compressed air is not needed - draining will do it. In fact, I doubt blowing air through the water jacket will remove any more water than just draining.

If you have raw water strainer--Do not forget to empty that-- Many do-Place some dryer sheets in the baot along with moth balls,,Mice can destroy seats...seen that happen more than once----Linda.

2001 san----- I just empty it.. I do not drain water, out- I run Af through the whole engine until I see it come out of exhaust..I run 5 gallons through-- ......My uncle has a 38 ft carver twin ,he runs af through that and all has been good...

eljayrx wrote: I do not drain water, out- I run Af through the whole engine until I see it come out of exhaust..I run 5 gallons through-- ......

Oh boy. Here we go.

M3Fan wrote: Two general assumptions that I see people get wrong on a regular basis are that 1. the T-stat needs to be open to let fluid into the engine and that 2. the exhaust is the "end of the line", such that if something is coming out of the exhaust it must have circulated through the entire motor. Both are incorrect.

There are a few different ways to get antifreeze into the engine (some much more complicated and hokier than others), but none can be guaranteed to provide an ounce of freeze protection if the water is not drained out first. To suggest otherwise would imply a gross misunderstanding of how the cooling system works.

Long story short: If you havent suffered freeze damage yet using your method, then youre very lucky!

Linda,

I am fine with your method and did it that way myself for many years, well maybe not quite, I think I drained first. But anyway, your first winter here, you didn't realize that this discussion comes up every year and there are those that say, don't drain, just pump through. Then there is a very large and vocal group that says that is bad, that without draining there is residual water in the block that remains there, even when pumping through AF, that can freeze and bust a block. There is one member that provides an accound of a cracked block using that method. But then there are a number of members that report "well I've done it that way for years and its always been ok". So my comment was just implying that you may have started that discussion up again, which is always good for getting a comfy chair and a bag of popcorn and watching.

"my weekend was great, thanks for asking" (still skiing comfortably down here....which has been a pleasant change this year, having just moved from 22 years in NY and then MA) Where in NY are you?

EDIT: Tim posted while I was typing....

eljayrx wrote: So our family has been lucky for say 30 plus years? so if-the exhaust is not the end of the line then what is??,,,,, TR?

Lucky? Yes.

In most simple cooling systems, there are 2 basic paths fluid takes through the motor. They are:

1. RWP-->thermostat housing-->circ pump-->block-->heads-->intake-->thermostat housing-->exhaust manifolds-->out the back of the boat

2. RWP-->thermostat housing-->exhaust manifolds-->out the back of the boat

The thermostat controls the flow out of the engine. If the thermostat is open, water will follow path #1. If the thermostat is closed, fluid will follow path #2.

Unless you remove the thermostat or intrinsicly know it was open (no idea how you would do this), if you do not drain the block, you have no way to determine which path the antifreeze took. It is entirely possible that it took path #2, and the block remains 100% full of water. Its also possible that its full of antifreeze, or a water/antifreeze mix of anywhere between 0% and 100%. If you are using marine/RV antifreeze, you know that it is not meant to be diluted, so anything less than 100% antifreeze offers diminished freeze protection.

So, like I said, without draining first, you can have no guarantee as to what % of antifreeze is in your motor, nor if it is sufficient to prevent a freeze. That is not the type of gamble I take with my boats, as draining takes about 3 minutes... but YMMV.

If you do not drain, after you run your 5 gal of antifreeze pull the block plugs and check color, better yet capture in container and test. As Tim stated it will be somewhere between straight water and a mixture depending on thermostat

I loosen my belts during off season and I detach all hoses to make sure water is not sitting anywhere. When I do that I hand rotate the RWP to get any water left in the housing out. Spring Means new Impeller for me this year. Gets about 180 at idle after a long WOT run. Thats my indicator.

MI-nick wrote: don't forget the two drain plugs on the V-drive. i always pour in AF...only need 2 gallons vs. 6 for the run through method...and pouring in is easy...

What kind of vdrive? Not being smart, had a Walters and only ever pulled the hose. Wasn't aware of any plugs

Just draining alone is fine if that's what suits your fancy. I've seen boats done each way for decades and they are fine either way.

No, the PCM Ford cooling system is amongst the most basic and my points above were most applicable to it. Its a great system- very easy to troubleshoot and runs very consistently. Its also very easy to maintain- surely your research has turned up the engine manual that describes the proper winterization process (ie, drain and fill)?

The path to fill the block (in the thermostat housing) is always open... and this is why the block can be filled even when the thermostat is closed. However, if the block is already full, and the thermostat is closed, the fluid in the block has nowhere to go, so no new fluid being introduced via the thermostat housing can enter. Instead, it gets dumped out the exhaust. The fluid in the block remains static until the engine is up to temp, at which point the thermostat opens and allows it to exit (intake-->stat housing-->exhaust-->out the back of the boat), and the engine again fills with cool new water supplied to the stat housing (from the RWP).

If water was constantly circulating through the block, then the thermostat would serve no purpose and the engine would never come up to temp.

I seriously feel sorry for you folks that have to winterize your boats.
Winterizing mine means remove the bimini, take the ice out of the cooler and put in warm water, put the drysuit and fleece and uggs in the skibag.

ok - thanks all. i think i'm good to go.

say i don't fill with AF and there is a little water in the RWP. I could purge this by running the engine for a few seconds after draining?

darren.