Evinrude 25hp 1977 exhaust conversion?

[OutboardDave]

Hi, all I'm new to the board and fairly new to OMC motors. I have acquired a 1977 Evinrude 25hp. I have always owned mercs and a few rudes in the past but am not real familiar with this motor. It does not have thru-hub exhaust. I would like to put an "Outboard Jets" jet pump on it. I am very familiar with the outboard jet pumps as I have owned a few in the past. My question is, they only manufacture jet pumps to fit this year and size with thru hub exhaust. Since this motor is not Thru hub. Can it be converted? Is the center section any different other than a seperate exhaust tube inside or does the thru hub exhaust center section have an exhaust manifold cast into the aluminum? Any help or opinions would be appreciated. Thanks

 

[1946Zephyr]

Re: Evinrude 25hp 1977 exhaust conversion?

We need to see what your model number is. 1977 25's were the first year of the through hub exhaust and 1976 25's were not.

 

[OutboardDave]

Re: Evinrude 25hp 1977 exhaust conversion?

Sorry should have included model number. It is as follows 25702H. I believe it is a 1977 but could be wrong. Thanks

 

[OutboardDave]

Re: Evinrude 25hp 1977 exhaust conversion?

Also curious as to what the H on the end of the model number meant?

 

[1946Zephyr]

Re: Evinrude 25hp 1977 exhaust conversion?

Yep, you're right, it is a 77 model. Let me check and see what the H stands for.

 

[G DANE]

Re: Evinrude 25hp 1977 exhaust conversion?

The 25 did not come out with thru-hub exhaust before late eighties. Only the 35 and larger had thru-hub.