Where are the plugs i need to pull to drain a 4.3L Mercruiser I/O?

Question

I just bought a Bayliner Capri and the owner told me to tighten the plugs and that they are under the manifold. I have no idea where that is.

Answer 1

The plugs that he is talking about are actually ptcocks for draining the water out of the engine block and exhaust manifolds. One is located on the right (starboard) side of the engine block, just in front of the starter. One is exactly oposite that one on the left (port) side of the block. There should also be one on the bottom of each exhaust manifold, right about center of the manifold.

Answer 2

You better make friends with a good boat mechanic!

The plugs to "drain" you asked about are on the bottom of the oil pan, but you can't get at it! To change engine oil, you have to pump it out through the dipstick tube!

The "tighten the plugs and that they are under the manifold" could only refer to the spark plugs. Why would he say tighten them? They don't as a rule "loosen" but do need to be changed as a maintenance item.

I got a feeling you should have had somone inspect that boat before you bought it. I buy boats (and jet skis, and cars,and so on) with problems all the time, but I know how to repair, and what needs to be repaired. You may have bought a lot of trouble, hopefully not. Find a mechanic (boat tech).