Just look at that hole!!

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Sinkingfast

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I bought a 1976 Evinrude 15 in a box, all apart. I am using these specs as I assemble, sans carb restrictor .

Has anyone ever seen this hole in the water feed tube in a stock motor? It is hole "P" at .040in.

As with most all outboards in a box there is a story to it.

It is going on a 1232 Jon boat. I'm sure by the end of summer '15 there will be a another story to tell.

Any thoughts on that hole?

https://www.racenbra.net/OMC_15A_Class_Engine.html

forgot pic...
 
Check out reed control plate or stop at .642in high? Item "M". Mine hits the crank at that height.
 
That makes sense..since the wet leg goes away with the short exhaust tube.

Thank you....I must aim that hole then..
 
"Check out reed control plate or stop at .642in high? Item "M". Mine hits the crank at that height."

Item M is the distance between top of the piston ring and the top of the piston in the specs.
I believe that funny looking M could really be a misprinted H which is 0.256+/-.020.

I have the same reed plate assembly as you do on a newer model. I port matched my intake and gasket to my reed plate openings, feathered some edges of my reed plate openings, installed boyesen reed valves, and bent my reed stops back a bit.

Both of the specs stated seem suspect. I would call the governing body's tech inspectors to get the correct spec. I'm sure this isn't the first time someone has run into this issue. I would also talk to someone very familiar with racing in this class if I could.
 
Ya know I almost tapered the back of the reed plate at each reed for flow but wasn't sure if that would make the reed less stable. I used 518 for the transfer cover, sans gasket. did some work on that lower cylinder reed offset and cleaned all flashing. Its going on a 1232 90lbs jon.

Now what to do with that open exhaust hole on the lower mid. After 1977 or so the mid had 3 5/8 or so holes with both exhaust tubes available it seems. I will be using a 5.5in tuner and will probably need that water tube spray to keep the mid cool.

Any other thoughts?

And thanks for the replies, no street cred here yet..
 

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