14 Ft. Capri won't get up on plane

[David E]

I'm new to this forum but thought this would be a good place to get some advice on my problem. I have a 1987 bayliner Capri 14' with a 50 H/P Force engine that afriend of mine was helping me with as this is my first boat. In his seal to show me how much he knows about boats he left a line in the water the got caught in the prop. I got the prop repaired and it will still not get on plane. I marked the hub and prop and the marks are still aligned with each other. The boat will cruise around but when you accellorate it acts like the clutch is plipping and revs up. It goes into gear forward and reverse just fine with no wierd grinding or anything. As it runs it sounds fine. Is there another fail safe mechanism in these engines or am I in for a expensive repair? Thanks for your help.
David E.

 

[Frank Acampora]

Re: 14 Ft. Capri won't get up on plane

That's a little bit knotty. There is nothing internally to slip. gears are splined to the prop shaft and drive shaft is splined to the crankshaft. So: if you are experiencing slippage at full throttle and it definitely is not the prop hub, then the only thing I can think of is that you are getting ventilation/cavitation at full throttle. This will make the engine rev-up and the boat will seem to go slower. A lot of times, it will happen only in sharp turns. If it is happening on the straight-away, then look for the following:
1. Engine mounted too high on the tramsom. The cavitation plate should even or slightly (in your case, less than an inch) above the bottom of the hull (the point of the VEE). Too high, and at low speeds the engine will act normal but at higher speed as the hull rises on the water, it will suck air and ventilate the prop.
2. The cavitation plate should be parallel or nearly so to the bottom of the hull. If you do not have power trim, usually this will be acheived by putting the tilt pin in the second hole out from the transom. Tilted out too far can have the same effect as above. Tilted in too far just slows down the boat--engine will not rev-up.
3. Something protruding from the bottom of the hull in line with the prop, causing turbulence and cavitation at higher speeds. (for example, an improperly placed depth finder transducer)
4. Broken or missing exhaust snout (assuming it is not thru-hub exhaust) allowing exhaust to foul the prop and ventilate/cavitate.

I would expect a 50 on that boat to top out at around 25-28 MPH (maybe a little more) with one person and light to medium load and the boat should plane at about 15-18 MPH.