Exhaust manifold, riser and elbow - flow path?

[saaristo]

Hi all. I’m dealing with 2005 MAG350. For winterizing purposes I have drained all the engine and poke the holes and everything. However, just to be sure I thought I will pour antifreeze through the exhaust manifolds. If I pull the hose indicated with red arrow and pour antifreeze via the opening into the elbow it should flow downwards and exit from the bottom of exhaust manifold, correct? Even when on that side the gasket has restricted flow hole and on the opposite side is a full flow hole, the antifreeze is routed inside the elbow to the opposite side and everything should flow down and still exit from the bottom and it shouldnt end up in the cylinders, correct?

 

[Scott06]

Hi all. I’m dealing with 2005 MAG350. For winterizing purposes I have drained all the engine and poke the holes and everything. However, just to be sure I thought I will pour antifreeze through the exhaust manifolds. If I pull the hose indicated with red arrow and pour antifreeze via the opening into the elbow it should flow downwards and exit from the bottom of exhaust manifold, correct? Even when on that side the gasket has restricted flow hole and on the opposite side is a full flow hole, the antifreeze is routed inside the elbow to the opposite side and everything should flow down and still exit from the bottom and it shouldnt end up in the cylinders, correct?
View attachment 420572

yes I usually pull the hoses at the thermostat housing lift them up and pour the AF in the hose. Some will leak out the exhaust as the elbow is open to exhaust as well as water flow up from manifolds.

 

[saaristo]

It just happened that I ended up with a gal of antifreeze and thats not enough for the “traditional” way of doing it. So as my bilge is spotless I poured that gallon through different parts of the engine, catch it and use it again. For example, I have water heater which heats up with engine cooling water, and it’s taken from the top of the block, so I poured the antifreeze into these openings and catched it from the distribution housing and block openings on the sides.
But I got a bit thinking whether pouring it into manifolds is a good idea when the exhaust gases are not pushing it out and whether it can drip back to cylinders.