Mercruiser Black Hawk drives

[TIMINATOR]

Has anyone had any experience with the Mercury Black Hawk dual prop surface drive? How much Horsepower will they RELIABLY take? Does Mercury still supply parts? Was there more than 1 drive ratio? How about effeciency compared to a normal drive? I've got a boat in mind to buy, but am REAL concerened about the drive deal. Thanks for any info anyone may have. TIMINATOR

[HavasuDreamin']

Well, I won't be of much help, but I think the writing is on the wall. Mercury made that drive as an option with a 502EFI only. They wouldn't put any more power in front of it. They also only made that drive for a short period of time.
Not sure if parts are available. Also, finding props at a reasonable price might be an issue. If it were me and this was going to be my only boat, I would opt for something with a standard bravo, XR, or imco.
HD :cool:

[dorC]

Actually, the 502efi was the only injected motor in the linup at the time. They needed the fuel injection to get a 500rpm idle to keep the off plane speed down.
Not knowing what engine you have, drive life is really dependent on you. You will damage the drive shifting at too high of a rpm. You will damage the drive with ham fisted throttling. You will damage the drive with full throttle planing. These are all issues with the bravo drive, just more accute with the bh.
I know of several bh's living happily behind hp500's. I believe they would live with close to 600hp-if you heed my above advice. I also know of several hp500's that have broken a bh. Of course, a hp500 can also break a bravo drive. It depends on the application and the driver.
Parts are still available-you just need to know who to talk too. Props are the greater concern. Right now they are out there, but hard to find. The last of the new old stock ones just sold. Expect to pay 800-1200 for a used set.
I believe there were 3 ratios available. 1.36, 1.5, and maybe 2.x
It's been said the drive will add between 7 and 10 mph to a boats speed. The bravo will swap right on, but be prepared for the speed loss. You can proably sell the BH for a little more than the cost of a used bravo.

[TIMINATOR]

Thanks to all! I hadn't even thought about props,been jettin for the last 15 years! This boat has a blown 572 w/intercooler, so I think I'll just can the whole idea. He has allready said that it idles at about 15 mph since the local boat "wizard" took the smooth idling 850 blower carbs off and installed stock 1050s, now it has to idle at 1100 rpm+. I think that since I don't know what else the wiz did,I'm gonna take a pass on it! Again, thanks for the info! TIMINATOR :) :)