200hp powerhead on 150hp XR6

[mgjtkt]

2001 150 XR6. Seller says 200 hp replacement powerhead was put on when motor was rebuilt. What else would have to be changed to make it into a true 200hp motor? I'm not familiar with big Mercurys so what questions should I ask. Thanks

 

[Dukedog]

its a direct bolt on swap. your kinda "stuck". unless ya know some exact specifics ta look for ya can't tell tha difference. even then its possible for all "bolt on" parts ta be from tha XR6. there should be a serial number stamped on tha block (unless its Merc direct replacement block). on tha welsh plug on top of tha block or maybe on tha port side "block flange" where tha two block halves meet....

 

[mgjtkt]

Thats what I need to ask him ( exact specifics ). What parts beside block would have to be different between the 150 and 200 ?

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[Dukedog]

About tha only thing that would be easiest ta spot are carb numbers. '01 XR6 used a wmv 16. On tha linkage side carb body they should be stamped 16-1, 16-2, and 16-3. along with a few other numbers that don't mean much. Tha 200 same yr. had 18's....Other than that almost everything else bolt on is tha same for either one...

What year is tha 200 power head?