Merc 1997 40 2 cycle . Where is the thermostat???

[psc653]

Replaced the impeller and other repairs to lower part of cooling. Afraid there are impeller parts in cooling system somewhere. My manual is in the mail!! How do I locate and remove/replace thermostat? See poppit valve on diagrams but not impeller. Overheat alarm is going off almost as soon as I start her up. Water flowing from prop hub and telltale coming out @ 100 deg

 

[Laddies]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

If it's a 4 cyl it don't have one and if it's a 3 cyl it and the popit valve are at the top of the exhaust plate.

 

[hkeiner]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

You did not provide a SN of your motor, so I do not know if the attached pic applies to your motor or not. It is for a 40hp Merc with SN OG531301 and above.

 

[psc653]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

Sorry. The serial ## is 0G493408

 

[hkeiner]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

That is the only pic I have for a 40hp Merc motor. Perhaps the thermostat location did not change much in the newer SN motors. I guess you can always take a look at that spot on your motor to see if it looks the same as the pic. Good luck.

 

[psc653]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

Well, went looking for manuals for this motor and other than spending $80.00 for a clymer, I found a merc manual on CD ROM from a guy in Australia on Ebay for $20.00 w shipping. Will see how that works and let you know. Most of the books I saw went up to 1989 or started w 2000.

 

[Laddies]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

Goto the cyl. block and crankcase section
http://www.usboatsupply.com/Mercury_Mercruiser_Parts_Catalog3a.php?mc=01&ms=3290&si=2435

 

[psc653]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

Yeah, but this is a 4 cilynder engine.

http://www.usboatsupply.com/Mercury_Mercruiser_Parts_Catalog3a.php?mc=01&ms=3310&si=543

 

[Laddies]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

If your engine is a 4 cyl. then I answered you question in my first post. Why is this thread still going on and on?

 

[psc653]

Re: Merc 1997 40 2 cycle . Where is the thermostat???

This thread is going on and on because I was assuming the presence of a thermostat. Without that option it would be nice to know where the next best place to check for potential blockage might be. I would like to solve the problem myself as knowledge gained is always valuable but don't want to break down entire motor. Just looking for voice of experience, I thought the mission of this site.