How many drain plugs on a 4.3 v6 merc

dalton565

Seaman
Joined
May 9, 2007
Messages
66
hey guys, had my boat already winterized but took it out today for a final run. I managed to locate 4 blue drain plugs and let the water out. However cudnt see any more, just wondering if i got them all or is there another one hiding somewhere.

Would like to get it sorted before the cold weather. its an 05 mercruiser 4.3 s/n ow325312
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: How many drain plugs on a 4.3 v6 merc

Do you have a closed cooling system? or is it raw water cooled? Power steering? I can assume you don't have a service manual or owners manual?
To answer your question, somewhere between 3 and 7
 

dalton565

Seaman
Joined
May 9, 2007
Messages
66
Re: How many drain plugs on a 4.3 v6 merc

she is raw water cooled and yes has power steering. I sucessfully removed 4 but didnt see anymore.

What do you think ?
 

imported_TheMan

Petty Officer 1st Class
Joined
Oct 19, 2006
Messages
224
Re: How many drain plugs on a 4.3 v6 merc

You will want to disconnect the hose from the power steering cooler..

Otherwise water will remain trapped in there and could burst the cooler.
 

Gary H NC

Fleet Admiral
Joined
Dec 1, 2005
Messages
8,972
Re: How many drain plugs on a 4.3 v6 merc

Should be at least 2 on the manifolds,2 on the block,one on the steering cooler,plus pulling hoses and draining them and the engine water pump too.

I take it a shop winterized it for you?
It needs to be done again and the engine fogged...Let a pro do it or you will be posting here in the spring,why is my engine leaking,overheating or water in the oil....
 

nathanfromal

Recruit
Joined
Aug 11, 2008
Messages
4
Re: How many drain plugs on a 4.3 v6 merc

Dalton,
just did this for the first time today after speaking with a technician. There are 5 on my 4.3L Mercruiser (2006 Tahoe Ski boat). Looking at the engine in from inside the boat, there are two on each side under the block and one (steering I think) in the front close to you halfway down to your left. They are blue plastic screw pins that are hand tightened. I drained them all and can still take the boat out if we get some warm days in December.

Oil/filter change and stabilizer in the fuel - call it good for the winter. Will service the lower unit in spring when I take it off the lift at the dock.

Nate,
Nashville, TN
 

Mikefc626

Cadet
Joined
Oct 31, 2008
Messages
7
Re: How many drain plugs on a 4.3 v6 merc

Would like to get it sorted before the cold weather. its an 05 mercruiser 4.3 s/n ow325312

I have the same engine, 2005 4.3L MCM, s/n ow324734. At least, I think it's the same; the s/n is very close.
If so, you have 5. The thermostat housing on the front of the engine has a c-shaped hose on the left (side with the fuel filter). At the base, there should be another blue plug. You have to squeeze your hand alongside the serpentine belts to get to it.
If you happen to not have one, unclamp the hose to get the water out.
 
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