18 hp Mercury 1984,Do I have a thermostat?

[OLJOCLARK]

This is as plain as I can put it.It's a 1984 18 xd.I'm waiting for my new impellar,and someone mentioned ,have you checked the thermostat? I'm not seeing one .Can anyone tell me if mine even has one?Or can you put me on a site with my motor parts breakdown.Thanks in advance,,OLJO FROM ALABAM

 

[Texasmark]

Re: 18 hp Mercury 1984,Do I have a thermostat?

Look at the rear of the powerhead where the plugs mount. If it has one rather than the water jacket being flat across it will have an extra cover held in place with a couple of screws on top of the jacket. I had an '84ish 85 hp 4 cyl that didn't have one. Merc didn't have them till they started upgrading their engines to new castings. I assume they thought the 40kv plug power would fire the plugs regardless of temp and a stat was just something else to fail....and they were right. Two of the few malfunctions I have had with my OB engines over the years were stats stuck shut; one a 70 hp OMC and the other the current 90 3 cyl Merc.

Mark

 

[OLJOCLARK]

Re: 18 hp Mercury 1984,Do I have a thermostat?

Thanks,Texasmark,all it has is the fitting that hooks to the pee hose that I can see.

 

[Faztbullet]

Re: 18 hp Mercury 1984,Do I have a thermostat?

If it has the raised cover(size of half dollar) on rear water jacket it has a t-stat. Most of the earlier ones did not and most of the XD series where equipped. That is the chrome bore block and is very sensitive to colling, if your going to use it in cold water like duck hunters do, I restrict the pee tube with a yellow butt connector as this will add about 20? to engine and help prevent colds seize of piston on chilly mornings....

 

[sidbre]

Re: 1984 60 hp do i have a thermostat

Re: 1984 60 hp do i have a thermostat

do I have a themastat on a 1984 60 hp mercury 3 clyender

 

[Texasmark]

Re: 1984 60 hp do i have a thermostat

Re: 1984 60 hp do i have a thermostat

do I have a themastat on a 1984 60 hp mercury 3 clyender

Your 3 cyl is probably a later design that incorporated numerous upgrades. Once upon a time the 60 hp Merc was a 6 cyl tower of power....when it came out back in the 50's. They just added a 2 cyl block to what was already a 2 cyl addition (20 hp to 40 hp) and wala, you had a 60. I have access to a picture of Roy Rodgers having one (he bought into Yellow Jacket boat co) on a 16' Yellow Jacket boat with all his kids in it. Was cheaper for Merc to build a 3 cyl and in the process added some new technology. Laddies can probably tell you when the 3 cyl came out.

I just pulled a '97 sales brochure and it said the 20 hp had an optional stat. 18 was very similar to upgraded 20. Again, no bulge on the back water jacket cover, no stat.

Mark