1991 mariner 2.5l powerhead

[chevy92]

I have a 1991 mercury mariner 150. Serial # 0D021990. I am in need of a new powerhead and while looking for one I see that my same powerhead is used as a 150 up to a 200HP what would I have to do to convert my 150 to a 200.

 

[Dukedog]

another power head... yours is a 2.0 150....... they are not anywhere near tha same..... they jus look alike at first glance... they're are only two 150 2.5 motors and they are tha efi and XR6.... even with either of those its not worth tha difference in modifying ta make 200 or buyin' a 200...........jmo

jan.... when lookin' ta buy a 2.5 200 ya need ta be able ta tell tha difference.... from '91 up they all look tha same to an unknowing eye... even tha 2.0 motors.

 

[chevy92]

Not to argue or doubt your information but how did you determine its a 2.0L? I have entered the serial # in multiple charts and websites and they all say it's the 2.5L.

 

[Dukedog]

https://webapps.brunswick.com/litera...yKbh4Qbi0QaNz0

 

[Dukedog]

tha ONLY 2.5 150's built are tha efi and tha XR6.... all other 150's are 2.0 motors.....most sites combine model group stuff but will designate a peticular part for for either tha 2.0 or 2.5 or by a serial number group... tha MercNet site above doesn't do that....

just ona side note... '91 was a "block change year".... all of tha 2.0, 2.4, 2.5's looked identical on tha outside and caused a lotta confusion to folks that had no idea of what ta look for to tell what was what... thats why ya gotta be careful when buyin' one without a serial number on tha block itself.............

 

[chevy92]

Thanks!!! You just saved me a whole lot of trouble