Mercruiser 3.0 Intake Manifold Question

[DocDoug]

While winterizing my Mercruise 3.0, I added antifreeze to a plug hole next to the exhaust riser. I expected the antifreeze to trickle from the block drain plug but it didn't. Any idea what the hole is for where I added antifreeze. I fear intake or exhaust. (I added 2 quarts in this hole.)

Thanks, Doug

 

[Bondo]

Re: Mercruiser 3.0 Intake Manifold Question

Ayuh,... Welcome Aboard,... Got a picture,..?? you might be right...

 

[DocDoug]

Re: Mercruiser 3.0 Intake Manifold Question

Ayuh,... Welcome Aboard,... Got a picture,..?? you might be right...

UPDATE: Tried to crank engine and guess what... hydro-locked. Ughhhh, 1/2 gallon antifreeze went into intake manifold. I removed the spark plugs and cranked away. Got all of the antifreeze out, I think. Cleaned spark plugs and started engine. It runs! :redface:Ran for 20 minutes then fogged engine and cylinders. Checked oil on dipstick. No indication that antifreeze got past rings into pan.

Lesson learned: After removing block and intake manifold water drains, ONLY introduce antifreeze via ear muffs at out-drive!!!

It looks like I escaped a $5,000 mistake. Lesson well learned.