Thermostat question

ub54

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May 14, 2018
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I'm now on my 69 Johnson 40 HP. Motor. It has a thermostat .My question is will water come out of the hole as soon as it starts or when it gets up to operating temp? And because this motor is new to me where does the water get sucked in at ? Thanks
 

racerone

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Exhaust comes out of that exhaust relief hole on the lower cowling.------After start up water will mist out of there too.-----After thermostat opens more water comes out.-----When pulling a skier water pours out !!-----You must install a new impeller on a " new to you " motor !!
 

ub54

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Yeah, I'm going to but didn't know how much water should be coming out at idle .but I still can't tell where the water gets sucked in. Is it the gap about 6 inches above the cavitations plate that separates the upper and lower units ?
 

oldboat1

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The water intake is at the snorkle below the ventilation/cavitation plate. There is a filter screen in there that can be blocked up -- might check it without disassembly using a small brad to clear any visible blockages in the screen.
 

racerone

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Agreed----behind the propeller is the screen.-----And it is difficult to run these on a hose.-----In a test bucket you must make sure that water is 6" above the pump as they are not self priming.----Any pictures of this " gap " above the cavitation plate ?
 

F_R

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Yeah, I'm going to but didn't know how much water should be coming out at idle .but I still can't tell where the water gets sucked in. Is it the gap about 6 inches above the cavitations plate that separates the upper and lower units ?

The amount of water varies with thermostat state. The 'stat constantly monitors temperature and opens and closes as necessary to maintain proper temperature. So it is NOT an either-or question.
 

ub54

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May 14, 2018
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Unable to do pix, I have no skill in that dept. But there's nothing wrong with it just the way their made. I was looking for slotted are as for water intake , didn't realize it could or would be that small . I'm gdone for today but I'll get on it first thing and get back with you guys. You're really great help.
 

ub54

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May 14, 2018
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OK, got that checked out all is good . Now for a completely different subject ,on my 1987 Johnson 30 HP . I understand on the needle valves . High ,low and all that . But where are they located on this carb ? If you're facing the carb at about the 10 o'clock position there is a needle.At 6 o'clock there is the bowl drain . my question is where is the high or low speed needles and what are they to be set at ? I can see the one at 10 o'clock but don't know which one it it or what to set it at? Sorry for the dumb and confusing questions , but I need to get out on the water! Imy not as dumb as I seem .. Thanks again and again
 

F_R

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Model number? Anyhow, generally speaking the slow speed needle is above the main air intake opening. The high speed fixed jet is behind the drain plug. No high speed needle.
 

racerone

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There is no high speed mixture needle.----It is a fixed " orifice plug " in behind that drain that meters the fuel.
 
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