Do you remove the thermostat before winterizing?

[mysticowner]

I'm worried about the thermostat closing while pumping in the antifreeze.
It's a 454, I know warm it up completely then pump it in. How do we know for sure it hasn't closed?
I'm 99% leaning toward removing it.
What do you guys do??
I'm in Pa so it gets dang cold outside.

 

[Bt Doctur]

Should you wish to persist in this method, you should really drain the water from the block and manifolds first.
After removing the plugs and probing with a wire/nail/drill bit to ensure draining you could just pour it in thru the hoses.

 

[Jay Bird]

I have always pulled my thermostat before running the antifreeze through the muffs. It is cheap insurance to make sure I get complete circulation. I also feel better knowing I have a new thermostat every year.

 

[Jimmy Buoy]

You have a valid concern. I did have a raw water cooled 454 in the past and winterized it myself for 8yrs without any issues. I didn't involve warming up the engine at all. It was all done once the boat was out of the water.

First, open all the block, oil cooler, and manifold drains (also poke a small wire in each drain to ensure no blockages from rust or scale). Remove the raw water supply hose from it's fitting on the outdrive collar.

Second, remove the thermostat and close all drains now that the water has drained.

Third, pour antifreeze into the thermostat housing and raw water hose until both are full.

Finally, crank the starter without starting the engine just a couple of quick shots (just to ensure that the belt driven raw water pump gets filled with coolant). You can then reinstall the thermostat and cover.

One final thing - if you have a hot water heater tied in to the engine's cooling system you will have to remove the hoses, drain, then fill with antifreeze too!

This process has worked well for me in the past, and another friend's boat too. If you're frugal, in the spring you can open the block/manifold/oil cooler drains and collect the antifreeze as it flows out of the open drain in the bottom of your hull too - you might have to use a coffee filter, but it seems a shame to toss antifreeze that is perfectly fine to use again.

Good luck!

 

[paulswagelock]

You can run on the muffs until AF comes out the exhaust. That will fill your manifolds, PS cooler, outdrive, and raw water pump. Then drain the block, remove either the Tstat housing or the main hose and pour AF in until it comes out the other opening. Bump the starter and pour some more in. You are now certain it went in. As mentioned, fill the hot water heat exchanger manually if you have one. Lastly, I drain my entire system when done and leave it empty for the winter layup. Air doesn't freeze...

It is really helpful to look up your cooling system flow loop online. You can follow the circulation path to be certain whatever method you choose gets everything.

 

[CV-23]

An empty block/heads/exhaust will rust quicker than a full antifreeze engine. I always winterized my Alpha1/350mag with the antifreeze pumped through the muffs but the Bravo1/454 I drain and fill manually. The raw water pump just seems to high on the engine to pump antifreeze from the outdrive out of the water. I agree draining the block seems the best idea after filling with antifreeze but you loose all corrosion protection inside the motor. It may not be that big of deal either way, Mike.

 

[Lazy Daze]

This comes up a lot around this time of year, for obvious reasons. There are tons of threads about this, but I'll just keep this short and sweet. The most assured way to protect your investment is to drain the block/mani's (no need to run the engine unless you were fogging it beforehand) and then fill everything back up using the hoses that are attached to the t-stat housing. You will use less AF this way and also be guaranteed of it being full strength. It's a 10 - 15 minute job, tops. And, yes, keep the pink in there.

 

[alwhite00]

I drain everything, Pull the t-stat, put it together w/o the t-stat and run it through the muffs till it comes out the exhaust. There are some hoses I can not drain completely so I feel better doing it this way. Then in the spring a new t-stat & gasket & done.

LK

 

[Gunn]

One final thing - if you have a hot water heater tied in to the engine's cooling system you will have to remove the hoses, drain, then fill with antifreeze too!

This comes up a lot around this time of year, for obvious reasons. There are tons of threads about this, but I'll just keep this short and sweet. The most assured way to protect your investment is to drain the block/mani's (no need to run the engine unless you were fogging it beforehand) and then fill everything back up using the hoses that are attached to the t-stat housing. You will use less AF this way and also be guaranteed of it being full strength. It's a 10 - 15 minute job, tops. And, yes, keep the pink in there.

Dennis, I took your advice last year and used your method to winterize my 4.3's. But I failed to think about the hot water heater exchanger that Jim mentioned above. Would your description cover the bases on that too? Obviously I had no issues this year with it, but...

Tom

 

[Lazy Daze]

Dennis, I took your advice last year and used your method to winterize my 4.3's. But I failed to think about the hot water heater exchanger that Jim mentioned above. Would your description cover the bases on that too? Obviously I had no issues this year with it, but...

Tom

Hi Tom,

No, it won't totally take care of the heat exchanger in the hot water tank. For that, follow the two black rubber hoses from the tank to the engine. It's simply held onto a nipple with a hose clamp. Take the two rubber hoses off their respective nipples. Blow through one of them, while letting the other hang down into the bilge. This will get most of the water out. Then, just hold one of the hose ends higher than the heater and pour some AF into it till it comes out the other hose. After you do this the first time, it takes about 5 minutes. Might take 10 the first time.

If the hoses haven't been off the nipple for a while (and no grease was put on them), use a slip joint pliers (or similar) and gently twist the hose till it "cracks" free. You'll know what I mean when it happens.

If the hose connections on the heater are higher than the lowest hose connection point on your engine, then most of it will drain by itself.

 

[CV-23]

BTW....I don't pull the thermostat unless it's not working. Just changed the one on my 454 and it was fine. Freshwater does not seem to hurt them but since I just got the 270 last year....I now know what's in it. I drain my hot water hoses into the bilge and then fill them with the pink stuff, Mike.

 

[Clam Bake]

This comes up a lot around this time of year, for obvious reasons. There are tons of threads about this, but I'll just keep this short and sweet. The most assured way to protect your investment is to drain the block/mani's (no need to run the engine unless you were fogging it beforehand) and then fill everything back up using the hoses that are attached to the t-stat housing. You will use less AF this way and also be guaranteed of it being full strength. It's a 10 - 15 minute job, tops. And, yes, keep the pink in there.

Thanks Dennis, I want to try your method this year. Is there any reason why the drain plugs - with the blue plastic knobs - would be permanently sealed off? I took my blue plugs out and tried to clean the holes with a wire and it does not go through. I then tried a screw driver pushing as hard as I could and it would not go through... I have not had the block drained in years, I always used the muffs method before this. Have you ever heard of the drain plugs being clogged this tough? I don't want to put a screw driver in and hit it with a hammer if there is some other reason the hole is not opening up. Do they ever have to be cleaned out with something drastic like a drill?

Regards, Pete.

 

[Lazy Daze]

Hi Pete,

Yes, it is possible that there is just so much sediment and scaling built up that it's totally clogging the holes. If you happened to notice, the blue plugs don't go directly into the block. They screw into an adapter. The adapter is screwed into the block. I'd suggest removing the adapters as that will provide a larger hole to try and get the crap out of there. Spray some PB Blaster on the fittings a few times (over the course of a few days to a week) before you start.

The longer that the scaling is left in there, the more it will build up (and catch more sediment) and clog the cooling passages.

In the meantime, try using a drill bit in the fitting that's on the port side. Your starboard fitting is a "Y" fitting, correct? That one makes a turn as it goes in so anything that is straight and unbending won't work. Twist the bit by hand and then look at what you have on the threads. It will probably look like black, flaky rust that will turn your fingers black when you rub the stuff between your fingers.

 

[electricaldoctor]

Once you get all of the crap removed, you can clean up the threads with the proper sized pipe thread tapping tool. Don't forget to use oil liberally when doing this and don't be in a big rush. Screw the tap in a few threads and then back out. If it gets too difficult to screw the tap in, then remove it and clean all of the crud off it. Repeat this until the tap goes in and out freely. Good luck.

~Ken

 

[Harmon]

Allright, I'm new to this winterizing alltogether. How do you run AF throught the muffs with out pressure?
Sorry of rthe simplistic questions but I'm a babe in the woods now:smt100

 

[alwhite00]

Allright, I'm new to this winterizing alltogether. How do you run AF throught the muffs with out pressure?
Sorry of rthe simplistic questions but I'm a babe in the woods now:smt100

I have a 4 gallon bucket with a fitting to accept a short hose on it, I set it on the swim deck and hook it up to the muffs, The impeller will suck it in.

LK

 

[Gunn]

I've used something very similiar to this available at West Marine on my 175.

I put it above the engine on the swim deck. Difference is I have a T fitting with a value so on one end I have the garden hose supplying water. All I have to do is turn the valve on for the A/F, turn off the water and the A/F starts to flow via gravity and suction.

On my 280 now I remove the hoses from the thermostat and fill them and discussed by Dennis above.

Tom

 

[Ms. Mymoney]

I drain the manifolds and blocks while its still warm, remove the hose from the FW strainer and attach to this horrible looking bucket I made. Suck in 5-6 gallons of the pink stuff and fog the engine until it dies. No thermostat removal. I do however have nearly a 15' beam which makes drain plugs very accessible. On smaller boats you may not be able to drain everything while it is still hot.