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Do I have water circulating? Don’t think so…

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bigtime_mcalpine

Regular Contributor
I’ve been a bit confused by where exactly the water is supposed to come out on my early 70’s Evinrude 9.9. At this point even though I have just replaced impeller I’m think I DO NOT have water circulating - do you guys agree? If I understand correctly I should see water coming out of upper exhaust port, right? See video below. also, is there a thermostat on these older (1974) 9.9’s? I don’t see one in parts list.

https://youtu.be/QI0Tu4VGmMs
 
Well it has a tell tale installed.----A 74 model did not have that from the factory.----And a 74 model was not white with a black powerhead either.----Yes these 9.9 all came with a thermostat from the factory.----Not sure what motor you have here.---Thermostat is clearly shown installed in the cylinder head.
 
racerone said:
Well it has a tell tale installed.----A 74 model did not have that from the factory.----And a 74 model was not white with a black powerhead either.----Yes these 9.9 all came with a thermostat from the factory.----Not sure what motor you have here.---Thermostat is clearly shown installed in the cylinder head.
Click to expand...

Damn, you don't miss much, do you, @raceroni. Correct, this is a frankenstein motor: powerhead from an early 70's, all the rest from a '77. With that in mind, the powerhead has no nub for a water outlet so the nub on the lower cowl is a dud. After I posted this I started to worry that maybe marrying the exhaust and lower unit with the older powerhead meant water has nowhere to go...hmmm. Would design of exhaust housing be any different I wonder?
 
No worries.-----The water that comes out the tell tale does NOT circulate through the motor.---It merely tells you that the water pump is working.----The tell tale does NOT indicate that motor is cooling properly.----So many , many folks do not understand the simple stuff.-----No difference in the exhaust housing either !---Cooling water on most outboards goes out with the exhaust.----Only a wee bit of water comes out the tell tale.
 
Ahhhhhhh, learned a new thing today. Thanks. So having said that, I feel / see zero water coming out with exhaust (where I’m pointing my camera in video clip). Water impeller is brand new so I guess I either screwed up the install and did not connect to brass pipe or water passages are clogged. Crap. Good news though is that it ran like a champ otherwise. Had a heck of a time starting it though. Took forever.
 
The service manual talks about wax crayons, you put a swipe on a specified part of the motor, & see if it melts.
That’s pretty old school. You can buy a thermal image gun for very cheap on sale.
simply point it at the factory specified point, & read the temperature...you’ll know whether it’s being cooled or not.
Tou should be able to hold your hand on the cylinder for a few seconds, if will get warm, but not so hot you get burned instantly.
 
Edchris177 said:
The service manual talks about wax crayons, you put a swipe on a specified part of the motor, & see if it melts.
That’s pretty old school. You can buy a thermal image gun for very cheap on sale.
simply point it at the factory specified point, & read the temperature...you’ll know whether it’s being cooled or not.
Tou should be able to hold your hand on the cylinder for a few seconds, if will get warm, but not so hot you get burned instantly.
Click to expand...

Well, took 'er out for a spin today. Good news, power was impressive (I've got a 15hp carb on there). Bad news is, even though I took an infrared temp gizmo with me and monitored multiple times at idle and regularly at speed, after I eased off on monitoring, it lost power and died. Last recorded temp was 154. It should be noted that I was using a cheapo temp gauge on head so it could have been off. Probably not too far off though as I had confidence that the idle reading at 133 / 135 seemed reasonable.

I hesitated to start it up again and got her going without issue about 15min later. Damn, guess I have to revisit my work on lower end and ensure that thermostat is not seized closed.

Thoughts? is 155 getting up there?
 
Others with way more experience than I would know. My service manual says two sticks are used, 100F & 163F.
At idle the 100F should not melt
At 5000rpm the 100F should melt, but the 163F should not.
So somewhere around 150F-160F seems to be the target.
I don’t have a service manual for the 9.9 or 15. The smaller motors were quite specific at where to measure, “lower port cylinder head screw”, & water jacket for the 8hp.
Holefully you chase this down. As Racer said, water comes out the telltale before it goes through the engine. Your pump could be fine, but a blockage elsewhere.
Have you gone through Leroys Ramblings... I think he addresses water circulation.
 
Edchris177 said:
Others with way more experience than I would know. My service manual says two sticks are used, 100F & 163F.
At idle the 100F should not melt
At 5000rpm the 100F should melt, but the 163F should not.
So somewhere around 150F-160F seems to be the target.
I don’t have a service manual for the 9.9 or 15. The smaller motors were quite specific at where to measure, “lower port cylinder head screw”, & water jacket for the 8hp.
Holefully you chase this down. As Racer said, water comes out the telltale before it goes through the engine. Your pump could be fine, but a blockage elsewhere.
Have you gone through Leroys Ramblings... I think he addresses water circulation.
Click to expand...
Thanks, that’s interesting. It would suggest I’m already running a bit hotter than expected at idle. Gonna pull the motor off boat ASAP and pull lower end off to inspect and blow some air through as well as pull water jacket off to replace/inspect thermostat. It seemed to start and idle fine 15min after the incident so I don’t think any real harm was done.
 
Update: pulled lower end. Water pump is working just fine. Tried to blow some air up the copper pipe though a d there seemed to be a restriction. Could a closed thermostat create this condition?
 
Update again: went to town on the powerhead, removed the water jacket and thermostat poked some zip ties through all orifices I could find and started the motor up. Water is most definitely coming up behind thermostat hole. It then spews out the back. Funny thing is, the back side of water jacket looks really dry. Here’s a pic of it below. Anyhow, Thermostat has been replaced even though old one was fine. Water jacket gasket replaced as well. Started reading up on Leroys ramblings and now he has me wanted to install a tell tale as per his instructions. There is still very little water coming out the rear exhaust holes. More of a drip of water from bottom edge. Mine is a long shaft with additional exhaust venting on the extension. I’m guessing most of the water comes out the bottom.
 
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