Mercury marine 165hp six

[Wesman07]

My wife just got the crazy idea to buy a 40’ house boat. All I know is it has twin 165hp mercury six’s in it. The boat is from 1977. I believe it’s a 250 CI?

Does anyone else know more about these motors?

 

[THE FRENCHTOWN FLYER]

V6 or inline?

 

[JackFish]

We had a Merc I/O back in the day and IIRC I think it was a Chevy motor.

 

[Max_Effort]

I know that Mercruiser I/O had 250 Cu/in, in-line six Chevy engines.

Also Chevy and GM, in-line 4 cylinder engines

 

[Firepower354]

For sure 250 I6 Chevy. Slightly hotter cam, and some had cast valve covers, fewer had cast lifter covers.