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'96 Mercury 40 Not Cycling Water, Lots of Smoke

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NickTheTrick3

New member
Just got done re-wiring the entire boat, adding new electronics and lights in all of the boxes. Did away with all of the old fuse panels and buss bars, and I replaced all wiring and updated all components to modernize everything. I completely redid the fuel system as well.
Here is my issue now. IT WONT CYCLE WATER, at all. I just replaced the water pump before I parked it, about two years ago, and it was pumping water great when I took it out last. Just to be sure, I took the lower unit out, took the housing apart and inspected the water pump. When I dropped the lower unit, I noticed two rubber washers/grommets/gaskets, one about 1 1/2" in diameter, the other maybe 1", sitting on top of the impeller housing. I did not think much of it. They were torn, so I just set them aside and forgot about them. I thought maybe I left it in there when I changed the impeller. Everything looked good, so I re-sealed the impeller housing, torqued it back down and put the lower unit back in. When I fired it up, it's smoking more than usual, blowing smoke and/or steam out the the pee hole, and I'm afraid to run it too long. So I am confused now. I need some advice here, and maybe an exploded view diagram of the cooling system. Why is this motor blowing smoke out like crazy, including out the the water outlet/pee hole?! I am an automotive technician, so I'm pretty good with these kinds of things, but boat motors are very different, from what I'm used to working on. I'll add some pictures of the bushings/grommets I found. Any advice would be much appreciated.
IMG_8593.jpg
 
The larger one goes on the driveshaft and just sits on top of the water pump, I'm not sure if it acts as a dirt shield or what but it isn't held by a clip or anything. The other one I'm not sure about, I can't say that all pumps are just like mine.
 
Thinking about the no piss stream thing, any possibility that the key that holds the pump impeller to the shaft is awol? It sounds like you have a lot of hot water so check that the outlet pipe from the pump to the power head is in place properly or you will just have a lot of water going no where useful.
 
I found a way to attach my drill to my shaft. When I spin the shaft with a drill, it spews water out of the copper outlet pipe, that goes to the powerhead, all over the place. So much so, that I can't even turn it at full speed with the drill, without getting soaked. So I would assume that the water pump is pumping, right? So perhaps my issue is with the seating of the outlet tube into the powerhead. Is there a seal or anything in between the copper outlet pipe and the powerhead, or does it just slide into place? Anyone know where I can get an exploded view schematic without having to subscribe to a site or pay for it?
 
Up at the top of this page is a link to engine repair parts, click on that find your engine, it shows all of the parts and their relative position. Yes it is likely that the outlet tube was not in the powerhead properly and you may find a use for your mystery seal.
 
Up at the top of this page is a link to engine repair parts, click on that find your engine, it shows all of the parts and their relative position. Yes it is likely that the outlet tube was not in the powerhead properly and you may find a use for your mystery seal.
 
As an afterthought, put the water pipe up in the powerhead first and then install the lower unit, it's much easier to see if your tube is in place or not. If the pipe won't stay up by itself the upper seal is missing or worn out.
 
Swagonmaster said:
As an afterthought, put the water pipe up in the powerhead first and then install the lower unit, it's much easier to see if your tube is in place or not. If the pipe won't stay up by itself the upper seal is missing or worn out.
Click to expand...

Great Idea. Thanks. And thank you to everyone else who replied so far! Lots of help. I'll keep you guys posted.
 
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