Merc XR2 thoughts opinions?

[Fr. Frank]

...I'm going to guess you built it for speed rather than economy.

It was actually nearly completed in being remanufactured when I got it. The best I ever got out of it was 6150 rpms at 46 knots on the GPS. (53 mph) At that speed/rpm and trim I was throwing up a 15' high rooster tail. Behind a Seafari, no less. Kind of funny if you think about it.

I bartered my work creating Mercury dealer's wireless computer network in return for the motor, for which they had been asking $5K. Previous to that, I had a Chrysler 120 on the back. No kidding.

...Is the 150 black max the same motor?

I don't think so. The Mariner Magnum of the same year is the same motor as the XR2/XR4/XR6/XRi. I think Black Max is just a marketing designation for all V6 Mercury outboards from the late 70's onward.

What should the compression range be?

My book calls for 125 to 140 lbs for the XR2 2.0L models. You also want all six cylinders to be within 10 lbs.

Also is there a difference between the blue decals and the red? I had once heard that one was aimed at salt water and the other fresh water not sure which is which can you shed any light on that and if there is any mechanical or material difference?

I honestly don't know.

[McGillicuddy]

Thanks again Fr Frank. Another question,
I was looking on Screamansfly for price comparisons and the things that stuck out about these motors was a.) their "bullet-proof" make up and b.) that they really generate their power in the upper end of their rpm band. Although I suppose this holds true for most 2-strokes.

Does the latter imply that they xr2s don't run well at lower speeds, or can they run effectively @ 3500 rpm and less? At idle or trolling?

Truth is with our big broad swells rarely would I have the opportunity or desire to run 35-45 mph offshore.