can coolant pass elbow into engine

[bobomara]

OK, I have winterized several times before with the muffs and 5 gallons of anti-freeze through the sea pump. Then when I pulled the plastic block plugs to check for anti-freeze coverage and screwed one back in and it broke, and I lost all the anti-freeze in the block, cause of the little fricken hole in the plug.
So I read some instructions about pulling the hoses from the thermostat and pouring in to fill, after pulling the exhaust ones and pouring in, I could not get the others off. Took a break and read some more. Then I ran across one post that said what I just did with the elbow was a bad idea because the fluid will pass its way back into the engine exhaust and enter the cylinders. Is this true?
I thought the elbows had coolant chambers separate from the exhaust. What are the chances of this happening with elbows only 3 years old. (no rust through internal walls yet)

 

[bruceb58]

Re: can coolant pass elbow into engine

The elbows are higher than the thermostat housing so unless the laws of gravity are different where you live, you won't have a problem. Of course if you lifted the hose above the level of the riser and you did this, there is a possibility.

 

[Bt Doctur]

Re: can coolant pass elbow into engine

It would be much safer if you drained the block and manifolds first because if the therm didnt open you would have A/F in the manifolds and pure water in the block.

 

[bobomara]

Re: can coolant pass elbow into engine

I think this post:
Mercruiser Winterizing Question #1,378,456 by ChrisCraftJohnny
answered my question. The document with the cross-section helps too.
But anyway, I appreciate any feedback