MErcruiser 140 water cooling question

petrey10

Petty Officer 3rd Class
Joined
Jul 1, 2007
Messages
82
where is the water supposed to exit on my 1971 Mercruiser 140? I keep having water get pumped into the boat from the engine and I believe the previous owner might have forgotten to put the drain plug back in after they were done and I am curious as to what you guys think
 

Bondo

Moderator
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Apr 17, 2002
Messages
71,357
Re: MErcruiser 140 water cooling question

Have you opened the hatch,+ Looked,..??........
 

petrey10

Petty Officer 3rd Class
Joined
Jul 1, 2007
Messages
82
Re: MErcruiser 140 water cooling question

yes i have but I don't know what is what because the manual doesn't show the schematics very well....I am not completely stupid
 

Dakota47

Senior Chief Petty Officer
Joined
May 22, 2007
Messages
722
Re: MErcruiser 140 water cooling question

Did you put the drain plug in?? its under the outdrive on the outside of boat?? quarter size hole, should have a metal/rubber plug turned in there..
 

Dakota47

Senior Chief Petty Officer
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May 22, 2007
Messages
722
Re: MErcruiser 140 water cooling question

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cheburashka

Senior Chief Petty Officer
Joined
May 28, 2005
Messages
715
Re: MErcruiser 140 water cooling question

I believe he's asking about the location of the drain plugs that are pulled when the engine is winterized.

On that motor there are two. One is a petcock that sticks out of the block on the same side of the motor as the manifold. On mine it's about level with the floor of the boat. The second is in the bottom of the manifold, and it's just a brass plug that threads in. There are quite a few small tapped holes in the bottom of the manifold, so it may be difficult to find the right one. The best way to do this is to run the engine on muffs and watch for drainage out the bottom of the manifold.

Another possibility is that there's a crack in the block. Keep your fingers crossed.
 

petrey10

Petty Officer 3rd Class
Joined
Jul 1, 2007
Messages
82
Re: MErcruiser 140 water cooling question

i am talking about the drain plug underneath the manifold...thats all I needed to know was that it is a drain plug and not something else.... I will go to hardware store tomorrow and get another 1/4'' plug....thanks a bunch!
 
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