[kriswd40]

I'm planning to finish winterizing my boat this weekend. I was planning to put muffs on and run anti-freeze through them into my engine, but I saw a video today saying you could simply remove the plugs and let the engine drain of water then pour in antifreeze in the thermostat housing and it will fill the engine just the same. Is that correct? That sounds like a much easier process and wouldn't waste antifreeze that will inevitably spill on the ground using the muffs.

[kriswd40]

Hmm... took a closer look at the engine and I'm not really sure where the thermostat is on the 4.3 either. Maybe this isn't a good option after all.

[kriswd40]

See this video around the five minute mark... this seems like so much an easier way to do it than using muffs.

https://www.youtube.com/watch?v=_bxpqmT1S3c

[ShabahZ280]

Interesting... Eddie from Long Island Boaters has some great tutorials which I've used many times, but I'm not sure about this method. I'd just stick to the standard way of winterizing with the muffs, it's tried and true... Plus it seems way easier.

If you're concerned with antifreeze spilling on the ground, go pick up a plastic baby pool to catch everything! This will help keep things clean.

[kriswd40]

Originally Posted by ShabahZ280

Interesting... Eddie from Long Island Boaters has some great tutorials which I've used many times, but I'm not sure about this method. I'd just stick to the standard way of winterizing with the muffs, it's tried and true... Plus it seems way easier.

If you're concerned with antifreeze spilling on the ground, go pick up a plastic baby pool to catch everything! This will help keep things clean.

Well, I ended up doing it this way. No replies until today and I needed to get it done yesterday (freezing weather and snow on the forecast for today). I don't have a heater so it was simpler than Eddie's video, just popped a couple hoses off and filled them up. I verified coolant was where it should be so as far as I can tell, I think this should be fine.

I don't like my muffs at all, they seem fine for the larger water volume from the hose but not good for the coolant, they seal fine on one side but terribly on the other (i hear people like the round ones better, I got rectangle ones). I didn't really have time to order a different set and wait for shipping. I tried the standard method and it just wasn't sucking in coolant very well so for me, this way worked way, way better... you know, assuming coolant did in fact go everywhere it should have gone and my boat isn't a wreck come spring

[grommett]

I changed to this method this year as well. The problem with using the muffs is getting your fogging oil to stop the engine at the exact time the coolant is about to run out. I also spoke to my guy who supplies my service items (and services engines) and he told me that using the thermostat housing does a more thorough job of getting antifreeze into the engine. This was my sequence.

Add stabiliser to fuel tank.
Run engine up to temperature and do an oil and filter change.
Change fuel filter.
Run engine again and use a whole can of fogging oil, getting the engine to stall as the can runs out (or have someone turn the engine off for you as soon as the can runs out.)
Drain water from engine (two drain plugs - one on each side) and manifolds. Use a small screwdriver or similar to aid removing any debris from block/manifold as water is draining but mind your fingers, it is hot.
Remove hoses from thermostat housing then remove thermostat housing from block. Mine was held with 2 bolts that go through an engine lifting point.
Refit drain plugs.
Pour 50% antifreeze mixture into the block until it comes out the exhaust also pour it directly down the hoses. (Adjust mixture depending on how cold it gets where you live).

Having done it this way I did feel it was better than the muff method.

I also did distributor and HT leads, next job is to remove the battery and put it on a maintenance charger. And fit my new control panel when I get it back from being powder coated!

[nglauer]

I purchased a kit from winter flush. It circulates coolant through your motor while running. Best purchase i made while I owned my diablo. Kit came with fog, stabil, lower unit oil, tools etc.