40 hp Yamaha water coming out of everything

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Douglasdzaster

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Location
Smithville,Texas
LOCATION
Smithville, Texas
I don’t know if or how bad a problem I have. I’ve turned wrenches for a long time but this is my first outboard and it’s been a project. I’ve had it running for a while now so I guess it was time. First thing I did was replace the water pump and change the lower unit oil. But that’s the extent of my knowledge when it comes to the lower parts. I was running it in a tank today to check out an idling issue. The hose popped out of the tank so I got down to put it back. Then I noticed water was coming from around the shift rod where it comes out of the lower unit. And directly in front of that is a hole I thought was for draining water when tilting the motor. Water was shooting out of that more than the tale tail. The upper exhaust port had a good amount coming out of it as well. The thermostat is new and the motor was running just under operating temperature probably because of the cool water I had running in the tank.I don’t know how normal any of this is but it doesn’t seem right to me so here I am looking for advice. If there’s a problem I want to fix it before going back to the lake or river. Any ideas or advice is always appreciated. Thanks
 
You could get a service manual. It will have pertinent info to help fix the issue.

Sounds like maybe the water tube isn't hooked up to the pump, just a wild guess here.

Maybe get a IR thermometer & check to see if the powerhead is getting hot.
 
CedarRiverScooter said:
You could get a service manual. It will have pertinent info to help fix the issue.

Sounds like maybe the water tube isn't hooked up to the pump, just a wild guess here.

Maybe get a IR thermometer & check to see if the powerhead is getting hot.

I was checking it with an ir thermometer. It never got up to full operating temperature. I think that’s because I had cool water running around the pickups the whole time.
After I’ve been researching each place the water is coming out I’ve read they’re all normal. They keep water from making its way up into the motor. I’m going to continue looking though and refer to the manual that I have. It’s not the best on something’s but it’s all I could find on this old motor. I’ve got a lot to learn about the lower unit and more about water circulation.
I appreciate the reply.
 
I don't know which 40 you have (there are about 4 different ones) but it doesn't sound unusual. Some of them had a little rubber gasket on the top of the foot that helped keep some of the exhaust water out of the shift rod area, but I don't remember which motors used that. May have just been the 25 twin carb 2 strokes since I saw a gazillion of those. Get the correct model for your motor and look up the diagrams on boats dot net to verify.
 
turbotodd said:
I don't know which 40 you have (there are about 4 different ones) but it doesn't sound unusual. Some of them had a little rubber gasket on the top of the foot that helped keep some of the exhaust water out of the shift rod area, but I don't remember which motors used that. May have just been the 25 twin carb 2 strokes since I saw a gazillion of those. Get the correct model for your motor and look up the diagrams on boats dot net to verify.

I’m sorry it’s a 1992 40 MSHQ. I’ve looked at parts diagrams but I’m not seeing anything to seal it. I’ve been reading everything I can look up and I’m seeing comments that it’s normal on different outboards . Maybe I just never noticed it. This water wasn’t warm at all though.
Not like it had been in the exhaust. I still may pull the lu tomorrow and check the water tube. Thanks for the reply it’s appreciated.
 
I've had several 2 stroke Yamahas. They will pump water up out of opening where shift rod is, they do have 2 open holes in lower casting that water flows out of. If you place fingers over holes, more will flow out of shift rod opening. I'd be more concerned with the level of water the tank got to for you to see this and possible temp of water recirculating as I've seen a water pump fried running in a barrel for hours. Just one man's humble experience and opinion.
 
Im with callison on this. If you have the correct amount of water in the tank, the water level should be so high that you can't see any of these noted leak points. If you fill the tank to be at least a few inches above where the water pump sits you should be safer and have a better idea of how hard it will piss when hanging off a boat at idle in the lake. I don't really put too much stock into the powerhead temp when running in a tank. They can run cool in a tank and then heat up a good bit more at wot in the lake and then others may even run a little warmer in the tank and then a little cooler aft some high speed runs. As long as they are not getting super hot in that tank Im happy and will just IR gun the motor on the water to see if its cooling properly.
 
The tank is cut a little short. The water just covers the cavitation plate. I keep a hose running in it to keep the water level up. Sounds like I need to stop using it. I usually flush with muffs but wanted to get back pressure on the exhaust. All I did was let it run out of the other holes since they weren’t submerged.
I replaced the fuel tank fitting today and it idled better. Still has a miss. After a while it went down on rpms again this time I gave it a little rev and it started behaving. I wonder if my carburetors or a carburetor is loading up with fuel at idle. I’m thinking of taking them back off for another cleaning and checking the floats. There was a little bit of fuel in the overflow on two carbs but not completely flooding. Ever since I tried using one of the new EPA tanks that pressure up I’ve had problems. It did flood the motor once. Got me an old tank with a vent now. I’ll refrain from using that tank anymore. I’d hate to mess up the water pump or something worse. I really appreciate y’all’s advice and you sharing your wisdom. I still have a lot to learn about outboards but it’s been a fun adventure.
Oh I’m planning on running it in the lake Monday and I’ll have my ir gun with me.
 
Here is what is happening.
What comes out of your overboard indicator is just a tiny portion of the cooling water sent to the powerhead to cool it. The vast majority flows through the cooling system after which it is dumped below the powerhead back into the exhaust housing and out of the thermostat relief and through the exhaust relief (depending on the make, model, etc.)and through the propeller hub. This is a LOT of water!
Some will pool up and eventually come out of all the places you have mentioned.
This is normal so you can relax.

Second.
Most water pumps are not self priming. Make sure you have the water pump covered with water when running in a bucket, small tank, etc.
 
Pappy said:
Here is what is happening.
What comes out of your overboard indicator is just a tiny portion of the cooling water sent to the powerhead to cool it. The vast majority flows through the cooling system after which it is dumped below the powerhead back into the exhaust housing and out of the thermostat relief and through the exhaust relief (depending on the make, model, etc.)and through the propeller hub. This is a LOT of water!
Some will pool up and eventually come out of all the places you have mentioned.
This is normal so you can relax.

Second.
Most water pumps are not self priming. Make sure you have the water pump covered with water when running in a bucket, small tank, etc.
Thanks Pappy, I appreciate your input. I’ve worked on a lot of equipment but this is my first outboard and it’s a whole new world for some of it. I’ve learned a lot just getting it running but I still have a long ways to go. I’m enjoying it for the most part then there are days I’m saying now what!
 
Look at the diagrams on boats.net.

Lower drive 2 section

Seal, damper and guide (#1 and #2 ) make sure they are installed. Those help keep some of the exhaust water out of the shift rod area.
 
turbotodd said:
Look at the diagrams on boats.net.

Lower drive 2 section

Seal, damper and guide (#1 and #2 ) make sure they are installed. Those help keep some of the exhaust water out of the shift rod area.

Will do thanks for the information it’s much appreciated.
 
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