Evinrude 79 70hp cooling

ken2010

Cadet
Joined
Jan 26, 2009
Messages
9
I have a 79 Evinrude 70 hp with a tell tale cowling water outlet. When running the motor it streams water like I do after a 12 pack. No overheating issues. Im used to these older engines spitting water out the dual hole tell tales (which it has) but it barely even dribbles. Shouldnt both locations be spitting like mad? Thanks
 

jtexas

Fleet Admiral
Joined
Oct 13, 2003
Messages
8,646
Re: Evinrude 79 70hp cooling

Hey ken, welcome to iboats. That's a great motor. The two holes on the back are "exhaust relief ports". At idle (in the water) and at low speeds when backpressure is greatest, excess pressure vents out those holes. But on the muffs you won't see hardly any water at all. Honest with ya, I don't ever see much water coming out there. Trust the pee stream.

To test your overtemp horn, find the tan wire attached to the temp switch on the cylinder head; there's a connector a few inches off the head, covered with a rubber sleeve. Peel back the sleeve and touch the connector to the cylinder head (keyswitch "on") - a steady tone should sound.
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: Evinrude 79 70hp cooling

the taletell stream, is an indicator that the impeller is pumping water, it is not an indicator that the thermostat is opening and cooling the motor.
 

ken2010

Cadet
Joined
Jan 26, 2009
Messages
9
Re: Evinrude 79 70hp cooling

Thanks for the quick responses. And yes, I love the motor. It runs really strong and has a great "sound" to it. I'll definately give the temperature horn test a try. It doesnt make a sound when starting, isnt it supposed to? Have to check on the thermo also, is there a way to test it? Guess I need to pick up a manual asap.

Side note on this engine, is there really no air filter on these models?

Thanks!
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: Evinrude 79 70hp cooling

The horns with the automatic start-up test beep don't come in until around 1989, but you could convert to one if you wanted. The horns with the automatic test beep have a second ground circuit for the test beep when you first turn the key to run or start.

In the meantime, you test the horn by disconnecting the tan wire a few inches from the cylinder heads and grounding the control end of the wire to the engine block with the ignition key in the run position.
 
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