Drain plugs on a 99 Mercruiser 4.3

[dmountaintop]

I can only find 4 blue drain plugs. I have a 1999 Bluewater Mirage with a 4.3 and the engine serial number is L361169.
I only found 1 on the side of the block, on the right side. I would think there would be one on the left side as well. I found 1 on the exhaust manifold on each side and 1 on the hose coming off the water pump. Any help? Did I miss one on the left side of the block? Thank you.

 

[Fun Times]

Hi there, welcome to iboats!

Yes you have missed one drain plug on the left side (portside) of the engine block, and if your in the path of that big cold storm coming out of Canada, you are going to want to find it soon. http://www.boatinfo.no/lib/mercruiser/manuals/mercruiser25.html#/58

Item # 7, Be sure to poke the holes in case there is any debris build up. Good luck.

 

[Bondo]

Ayuh,.... If ya got a knock sensor, the plug is hidin' behind/ below it,...

 

[dmountaintop]

I guess I am wrong on which side of the engine block I found the plug. I was looking (facing) the engine. Sorry about that. I found one on the port side of the boat. I didn't find one on the starboard side of the engine block on the boat. Is there supposed to be one on the starboard side of the block? I found 2 on that side, one on the exhaust manifold and one on the water pump. Thank you.

 

[Fun Times]

Is there supposed to be one on the starboard side of the block? I found 2 on that side, one on the exhaust manifold and one on the water pump. Thank you.

Yes, there will be 2 on each "side" (block & manifold) and one at the "front" of the engine on the starboard side like you already found for the water pump.

So for how you are describing this, 3 on the starboard side of boat, or on your left if you're facing the engine.

 

[dmountaintop]

Bummer. Where would the one for the block be on the starboard side? I looked and looked and looked...

 

[Fun Times]

Can you take some pictures of the starboard side of your block and post them. Under the exhaust/above the oil pan area.

 

[dmountaintop]

No Title

Here are 2 photos. The blue line is the water line for the shower on the stern.

 

[Fun Times]

Thanks, that made this easy. The red hose (whatever it's for on your boat setup?) has been converted from the block drain port to something else such as a hot water system or heater maybe.

Pull off the red hose and stick something into the brass fitting to ensure there is no blockage like sand for example. It should drain water for over a minute or two. Sometimes it's best that you keep poking the hole as it drains. Recheck/poke the other engine block drain just to be safe.

 

[dmountaintop]

Thank you! That was it. And a lot of water came out. (whew) Now, I noticed another concern. the shower on the back of the boat. There is an electric water pump mounted in the back. Does that need to be drained? I took the shower head off and drained that line. I don't see any plugs on the electric pump. And it is tucked way in the back behind the fuel lines, etc. I just bought this boat this year and there isn't an owners manual. So it's a learning process. Thanks again!

 

[Fun Times]

Yes you need to be sure any and all "water" is out of all the water systems by running the pump/s until it's dry. I don't believe there is any plugs on the pump though.

See if this video helps you any. https://www.youtube.com/watch?v=PA_LePaLy0E

Where do you live?

 

[dmountaintop]

Thank you for the video. It was helpful and good information. Thank you again for all your help. I live in Post Falls, Idaho. And it got cold, quick! So I'm glad nothing got damaged.