David1187: How long do you run antifreeze through the engine?
Mark Jones: We prefer to reinstall the plugs and run antifreeze through the engine. This does 2 things; First it protects the internal engine coolant passages from corrosion. Second it prevents freeze damage in the event that it displaces any retained water in the event that the engine did not completely drain.
Leon Nephew: Is it ok just to leave the blue plugs out untill next spring
henry cole: Stern drive type Boats should all be "closed loop" cooling system. That's what the engines designed to be. And you won't need to winterize ever again. Plus your motor will last much longer.
Mark Jones: Leave the antifreeze in the motor until next spring. This helps to prevent corrosion.
sonnygon: do you drain the antifreeze when you are done ? do you leave it in the motor until next spring ?
jduplan: Great video! After reading comments, I am still puzzled. I have observed at my local marina that the guys fog the engine as they are taking the boat out of the water. Only later do they winterize the engine eg. get antifreeze into the engine. How the heck would they go about doing that without running the engine???? Can this be done DYI ???
Performance Product Technologies: This boat is equipped with MerCruisers patented Manual Single Point Drain System. By turning of the blue knob and letting it sit for a minimum of 5 minutes you will drain the cooling water out of the engine block, manifolds, coolers, hoses and the all of the rest of the cooling system. Therefore this engine doesn't have nor require the removal of the traditional 'drain plugs'. We always back this up with running propylene glycol through the engine to insure that the engine will be protected.
Performance Product Technologies: his fuel supply line. We've winterized hundreds of boats this way for years and years and have never had any complications or issues what so ever. I have been in many 'most correct way to winterize' and 'fill up the gas tank before storage or keep it empty' discussions at MerCruiser training facilities with dealers from all over North America and they have all ended with; If what your doing is working at your dealership in your market… then keep doing it. Sorry for any confusion.
Performance Product Technologies: and then dumps out the exhaust. I also agree with you that by the book(MerCruiser Service Manual #31 page 1B-86) that MerCruiser suggests making a 5 gallon 'fuel stabilizer roostertail' with 2-cycle oil, fuel system treatment and stabilizer to run through the engine to stabilize and fog the fuel system and cylinders. Our method outlined in the video has proven to be just as effective and easier for the DIY boat owner to accomplish without having to purchase a external fuel tank and disturb
Performance Product Technologies: I agree it is a little confusing that the video is laid out so that the fogging comes before the Antifreeze. But we are actually pumping antifreeze into the engine while fogging it in the video. We didn't think you could see the antifreeze start to cycle through the engine and then dump out the exhaust, due to all the smoke, so we shot the last part without fogging to show how you need to make sure the antifreeze cycles through the cooling system
bon vivant: Yes, you should fog the engine last. Plus, they didn't remove the plugs?
lakewood85: Glad I don't have to go through this hassle.
RadioguyJ: Nice video, but......why are you fogging the engine then running the engine on antifreeze? You're just burning off the fogging oil anyway, not to mention fogging an EFI is no longer recommended.
Winterizing a Mercruiser 5.0L MPI Marine Engine and Alpha St5
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