Jump to content
My Monterey

MOST - Blue Plug on Engine

Recommended Posts

I have a 2001 302 with twin 5.0 Mercs. In the bilge, I found a blue plug (a T top with a screw bottom - picture attached). I see several of these plugs located on each engine (one in front and one on each side). At first I thought this plug is used to drain the water from the engine during winterization. But when I start the engines, I see no water running into the bilge and the engines do not overheat. Can you tell me what this plug is and where it may be located on the engine? Does it have anything to do with the outdrive? I ask because I seem to be loosing gear lube from the reservoir tank (from the full line to the fill line) each week when I am away from the boat and it is not in use.


Share this post

Link to post
Share on other sites

I have a Monterey 248 lsc with a 5.0 These plugs on my engine are only for draining the water.

Is it possible that someone may have dropped it in the bilge while they were draining the water

On the out drive there are 2 screws with washers they are used to drain the outdrive fluid. If you can take your boat check those screws




You can go to Mercurys website and in the upper right hand corner you can add your engine and look at all the parts.





Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...