Johnson Evinrude Comparisons

[Brokeback Johnson]

We own both a 1968 Johnson model FD22 20 hp and an Evinrude model 18803 18. What are the differences that account for the extra 2 hp with the Johnson?

 

[tootallofwa]

Re: Johnson Evinrude Comparisons

We own both a 1968 Johnson model FD22 20 hp and an Evinrude model 18803 18. What are the differences that account for the extra 2 hp with the Johnson?

They have the same bore and stroke. Ring clearances are different, so they may have different pistons. Could be a different carb. Could be how their HP was calculated. "They're the same damned engine"

 

[DJ]

Re: Johnson Evinrude Comparisons

We own both a 1968 Johnson model FD22 20 hp and an Evinrude model 18803 18. What are the differences that account for the extra 2 hp with the Johnson?

Marketing.

 

[tootallofwa]

Re: Johnson Evinrude Comparisons

Paint color!!!

 

[F_R]

Re: Johnson Evinrude Comparisons

I think you will find that the 18 cylinder head is part number 378557, while the 20 head is 381151. The pistons, rods, and crank are the same. In other words, the 20 has a high compression head.

 

[tootallofwa]

Re: Johnson Evinrude Comparisons

I tried to make sense of that... I still think it's paint.

 

[Brokeback Johnson]

Re: Johnson Evinrude Comparisons

Always wondered about this one........normally the sisters were identical engines. Can you folks think of other models that were marketed with a stated hp difference?

 

[F_R]

Re: Johnson Evinrude Comparisons

I tried to make sense of that... I still think it's paint.

They dinked around with the compression some more by changing the pistons and made a 25 out of it. Yeah, paint too.

I haven't seen anybody that can tell the difference in performance between the 18 and 20. But it put a bit of a kink in our get-a-long when we were trying to sell the 18 when the Johnson dealer across town offered 20hp.