[rusty]

After several years away from boating,I'm back in it .I'm glad I found my Z210 and I'm glad there is this club(all the info is awesome).Anyway,the duo prop design is relatively new to me.I like it,which is a good thing because I have it,but I'm not as familiar with it as I am the single prop design.My question is simple-for you prop buffs-is a 28 pitch normal on the 5.7mag B-III much like a 19 or 21 is on a single prop style?

[WetWilly]

Hi rusty,

The short answer - Yes, if they're the original props.

Now the reason why - Our 7.4L has a set of 28P props so it's natural to think a 5.7L with the same pitch would be over propped, but in you're case, there are two factors that can makes this possible.

#1 is gear ratio, ours is 2.00 R (right-hand rotation). Look at the the silver strip at the bottom of the "Mercruiser" decal on the port side of your outdrive, you should see a number stamped in the decal, that's your gear ratio.

#2 is weight, your Z210 comes in around 2900lbs dry where as our Z240 tips the scales around 4100-4200lbs dry, 1200lbs makes a big difference in a boat.

The best way to tell if your Z210 is propped right is to record your RPM at WOT. For the carbed and EFI models the RPM should be 4400-4800RPM and 4600-5000RPM for the 350 (5.7L) MAG MPI.

BTW, I read somewhere, the WOT RPM test should be performed with two people aboard, no additional gear and a 1/4 tank.

WetWilly

[rusty]

Thanks for the info Wet Willy.I believe the props are original based on the fact that the pevious owner had all service records since day one.I've not had her at w o t yet but close.The rpm s were around 4700-4800,she felt like she still had a little more to go and it was already scary fast! The speedo was showing around 65.I'm not sure how accurate that is but she was movin'.
Once again,I appreciate all the info provided by everyone in this club,it has certainly added to the excitement of getting back into boating.

[WetWilly]

Hi rusty,

As our Speedos are really glorified air pressure gauges, their accuracy is questionable to say the least, though several members have stated that theirs were only a few MPH off from GPS readings at the upper end. Anyway, the '98 Mariah brochure does list your Z210 having the capability of 55-60mph with the 5.7 and that is still pretty fast!