How many drain plugs in GM 4 cyl?

[swabby61]

With -6 degrees expected in a few days, I drained the water out of my 1980?GM 4 cylinder 140 hp. I have no manual with this newly acquired boat so I'm working by sight and feel. So far I have only found 2 water drain plugs. One under the intake/exhaust manifold and one near the bottom of the block on the same side. Does anyone know if there are any more? Thanks!

 

[Bondo]

Re: How many drain plugs in GM 4 cyl?

Ayuh,..........

You make No mention of What you're working on,.... So I'll Guess....

If it's a Merc. of that vintage,....
There'll be another Drain on the lower aft corner of the exhaust Riser.....

I'd also pull the Big Hose from the circulating pump.......

 

[Don S]

Re: How many drain plugs in GM 4 cyl?

When you are draining, once you take those plugs out, use a piece of stiff wire to clean the holes out of any corrosion, sand, mud, etc that may have accumulated over the opening.