1969 Merc 75 Cooling System Questions

Hello,

I recently purchased a 1969 Mercury 75, serial number 2534336. I started it briefly in a barrel of water but didn't see water spurting from any ports, so I shut it down. I am not familiar with the location of the water exhaust port(s) on this engine. Intake is shown in the generic manual I have, but exhaust is not. Can someone tell me where it is located? I've read in other posts that there are some small idle ports. Is this true?

Also, although my generic manual refers to a thermostat, I can't find one on this engine. Does it have one?

Lastly, there is a "Flush" port on the starboard side lower unit. What is this for and how is it used?

I'm working on getting a good shop manual but meanwhile could use a little help.

Thank you in advance.

Re: 1969 Merc 75 Cooling System Questions

http://www.youtube.com/watch?v=gSWCV2mJz8Q


run these tests budday drop your lower unit and check your impeller as well

Re: 1969 Merc 75 Cooling System Questions

Thanks for link to that video. I found another video by the same guy which shows how to use the flush port.

I still would like to check the thermostat. Can you tell me if this engine has one?

Thanks.

Re: 1969 Merc 75 Cooling System Questions

To answer my own question, this model does not use a thermostat.