Cylinder heads drain

[New2Boats]

I would like to thank everyone ahead of time for any help with this issue. I have a 95 1800 with a 4.3l. I just bought it and the previous owner said there was a leaky hose clamp. When we hooked up water to it to check out the leak I noticed on the left side of the motor there was a plug on the side of the head I could see water coming out. This was without the engine running. It appears to me to be a drain plug. It's a outer plug and then it has a threaded inside. I figured easy fix, so I brought it home. I could not get this plug out and that's when I noticed threads on the inside of the plug. I then thought it might be a drain for the heads. I checked the other side and its the same. I did not notice water coming out on that side though. My question is, are those supposed to be plugged up? Thanks again for any responces.

[mmwjr]

I’m not aware of a drain plug on the head. Do you mean the exhaust manifold?

[New2Boats]

No not the exhaust heads that stick up. There is 2 cylinder heads mounted on the motor just like a car motor. Water circulates through them. They are right at the bottom of the heads. About the middle I think

[New2Boats]

Ok, so correction, not on the heads but on the block. Just above the oil pan. Sorry for the confusion on my part. Trying to figure out how to post a pic.

[New2Boats]

https://photos.app.goo.gl/Msp925gGjFFoMAn27

[mmwjr]

Ok, yes these are drains on the block. The plugs should only be removed to drain the engine for winterization but be installed for normal operation. In your picture it appears you have a portion of a brass drain plug.

May be something like this:

https://www.ebay.com/itm/25740091644...yABEgKvFfD_BwE

[New2Boats]

Looks about right. Once again, sorry for the mix up. Thanks for all the help.

[mmwjr]

Originally Posted by New2Boats

Looks about right. Once again, sorry for the mix up. Thanks for all the help.

You’re welcome.

[shrew]

I just hook muffs up to a hose and run propylene glycol through the outboard. I don't bother draining the block. Then leave it stored in the Down position.

[HavreDeGrace2400]

Is that a picture of an unplugged block drain? You cant run with like that right? Unless the drain is clogged which it seems they are prone to be.

[mmwjr]

Originally Posted by HavreDeGrace2400

Is that a picture of an unplugged block drain? You cant run with like that right? Unless the drain is clogged which it seems they are prone to be.

Yes the plug is missing in the picture. While the engine will run water will come out unless the plug is installed. Yes this drain is prone to getting blocked by scale from the cooling passage.