Cooling system on 1985 Merc 18hp

[Pascastel]

Hi,
I have this motor for 3 years now. It has been working perfectly. But I am wondering why water is not coming out of the pipe behind the sparkplugs (on the back of the motor when attached at the boat).

The motor is cooled, because water is coming out of the exhaust holes few inches below the back of the head. The motor never burnt, even when we were using it 20-30-40min in a raw. The impeller is in a very good state, like new.

It is normal ? Should I worry for this ?

 

[Bosunsmate]

Re: Cooling system on 1985 Merc 18hp

try putting some fishing line or wire up there while its running and see if it unblocks it, all sorts of things climb in there and get stuck or get blown through from the impeller and block it.
The smallest of particles seem to block it at times.
You can also pull it off and blow through it to see if its blocked.
I think that model has it above the top spark plug, so you do really want to check water is getting that far up the head

 

[Pascastel]

Re: Cooling system on 1985 Merc 18hp

Hi... Your advice worked. I cleaned the pipes with air. The water finally went out. It was just dust...