1983 DT40: Part question.

[Treed01]

First time poster so hopefully this thread is in right area.

I am in the process of restoring a 1957 Lonestar with a 1983 DT40 outboard.

My question: Is this hole an exhaust or water discharge point? Immediately to the right there is a small pee hole that is working properly. My old service manual labels this as a discharge port and want to clarify before running if I have an issue.

Thanks in advance for any help.

[Solarman]

Yes, it is a partial exhaust, mixed with water pump water. At idle there is a slight amount of water mixed with some of the exhaust. This exhaust port shows you the thermostat is cooling the motor, and should not get excessively hot.
The remaining exhaust and water exit through the prop.
The tell-tale hole shows that the water pump is pumping water.

Good luck, post back if other questions.

[Treed01]

Thank you for your reply.

So I should have some water coming out of the exhaust port as well? Currently I only have water coming from the small “pee hole” to the right of partial exhaust port.

[Treed01]

After researching some more through the forums it looks like I have answered my own question. I either have a blockage somewhere along the tell tale or bad thermostat. Impeller is new and was installed by an outboard mechanic (kinda pissed he missed the telltale issue however)

[Solarman]

As stated above, a slight amount of water from the midsection is normal. You said the tell-tale was working good? The water and exhaust at the midsection will increase when motor is in the water (back pressure on prop when submerged).

When the motor/thermostat is cold, there is less water cooling the cylinders/powerhead. When the motor heats up, the thermostat opens more, and you will get more water mixed with the exhaust. But at the midsection it might still be a slight mist, or a little more. When the motor is in the water, it could be more than a mist, depending on water flowing through motor at different speeds/rpms/forward movement?

Good luck, post back if still having problems.