63' Evinrude Speedifour Exhaust issues

[wagemaker1]

Hello all,
I have a 63' Evinrude Speedifour that is giving me fits. When I run it in the tank, with the cowling off, there is a tremendous amount of exhaust coming up from around the powerhead (down inside the lower cowling). If the wind is blowing right, you can see the exhaust being sucked into the carbs. and the motor begins to bog down. Then when I put the cowling on, it pretty much stalls out. What could this be? I pretty much ripped apart this engine last summer, and thought I checked everything, guess not.......

Also inside the outer housing, mid shaft, there is a foam (or neoprene) gasket. It is pretty beat up and torn. Was this to prevent water from going up into the engine, or for exhaust?

Any help or insight is greatly appreciated!

 

[flintcreek]

Re: 63' Evinrude Speedifour Exhaust issues

Between the power head and mid section there is a exhaust gasket, baffle and exhaust gasket but they are both hard gaskets. I am replacing one on a 65 18 hp right now with some of the same symptoms. Also you have the side exhaust plate and baffle with 2 gaskets. My motor is actually missing the baffle and one of the guys on here told me it is not really necessary, helps keep any water from getting to the bottom crankshaft, but not necessary. Hope this helps. I will try to keep a watch on your post, if I learn more I will share.

Flintcreek

 

[wagemaker1]

Re: 63' Evinrude Speedifour Exhaust issues

Thanks Flintcreek, I do appreciate your time. Sounds like I have more work to do to the engine......

 

[wagemaker1]

Re: 63' Evinrude Speedifour Exhaust issues

To those who are having similar issues like I had, here is an update. I tore the engine down again, and discovered a failed gasket. It ended up being the powerhead adapter gasket. I replaced that gasket, put the engine back together, put it in the tank, and still had a huge amount of exhaust "rolling" up to the carburetors. Upon further investigation I found the culprit. The little oval opening to get to the shafts going to the lower unit, didn't have a plate inserted. When I first received this engine, it didn't have that plate, which I thought was weird......but ohh well. I went to one of my 1955 big twin engines, removed the similar plate and found it fits perfectly. Fired the engine up again, and the exhaust is now exiting the engine where it should. Just another item to put in my oops log.