Trojan Boat Forum

Hi all, I'm a new member to the forum and this is my first post, not a newbie to boating though. I bought a '72 F-25 FB at a great price, FREE! Just removed the Flybridge cause I'll never use it, too small.
However. the blown 350 Mercruiser that was in it was removed by the last owner (which actually saved me some time). I have purchased a newly rebuilt 318 raw water cooled engine and straight drive velvet trans (which I plan on removing and selling next spring) Here's my question finally: I do not know what rotation the engine is, I have looked at other threads here and found a few relating to putting an opposite rotation engine on my Borg-Warner V drive, removing the front pump and rotating it 180 degrees. I realize I have a 50/50 shot here next spring when I fire the engine up in my driveway and determine rotation. If I do have the "wrong rotation" and flip the pump, do I also have to do something with the reverse gear and I suspect a new prop? Where can I get the prop? Looking for some advice guys! Thanks, Rob.

Rob,
I am in the process of repowering my 1980 F25, replacing the seized 318 with a rebuilt 350. The 318 was apparently an automotive block and counter rotated. The BW drives in this class are 1:1 or pretty close so forward and reverse are comparably geared. I replaced my prop and have the old one, a 13x9. Look me up in the Spring if you need it.

Also I recommend checking the dimensions of your shaft and noting it in your maintenance log. Mine was not original and was 4" too short once the new engine and drive were in mock-up. This left the prop right against the strut, not good. I was lucky enough to not only find someone on our creek who was refitting an F25 but to buy his spare shaft that was the correct length.

Look at the Pump on the new engine's velvet drive and see what direction it is set at then make sure the v drive is set the same if not rotate it.

So there is no confustion I will add
Even though the the gear is the same Ratio foward and reverse you can not use the gear to reverse out put direction , It must be the same as the engine you rotate the pump to match the engine . You can not run it in the revese postion and use it as forward ( some gears you can but not a velvet drive)

Since he is useing the same gear( asume mounted in the same place) as came with boat shaft lenth sould not be a issue

RedBelly, saw the pics you posted. Nice project, I have the same here. Love this boat. Anyway, as Prowlerfish said shaft length wont be an issue cause my vdrive, shaft, stuffing box and strut havent been touched. I'm just doing my diligence because of Murphy's Law, 50/50 and I usually lose!
Prowler, I will check velvet drive tomorrow and post again. So break it down for a guy who has had stern drives all his life, and has mild learning problems!...."If my rotation at my flywheel is opposite of the arrow on the front pump of the Vdrive, my options are: A) Get the right rotation engine B) ?????

Good thing I ignored the mechanic and replaced it all then. It was originally suggested that I just replace the engine and reverse the drive. But I wanted a freshwater cooled rig and the 350 was cheap. Thanks.