Engine revs high prior to going on plane.

[bart98stang]

Greetings everyone. I really hope your boating season is going extremely well. I have a '88 Sea Ray Seville 18' with the original Mercury 135 engine. Whenever I increase the rpm of the motor I always take it slow and easy. As I'm increasing the rpm's the bow raises as expected then all of a sudden the engine rpm's take off as if I'm "spinning the tires" and then the boat goes on plane and takes off. The numbers stamped on my prop are Quicksilver 48 13700 A40 19P. I'm a having a problem with my motor or maybe to much prop? Thank you for your time and assistance.

 

[Mark42]

Re: Engine revs high prior to going on plane.

Could be that the motor is trimmed out too much, or mounted too high and the prop is ventilating (sucking in air) causing it to rev up. Or the prop could be slipping on the hub (spun hub). That can be repaired.

Check the trim setting, and try getting on plane with less trim and see if that reduces or eliminates the problem. If not, bring the prop to a shop to have it checked for a spun hub.

How long have you had this boat? Did this problem just start or has it always done it?

 

[bart98stang]

Re: Engine revs high prior to going on plane.

Mark, thank you sir for your reply. I have only owned the boat for just a few months and it's done this just about everytime. I will definitely play with the trim the next time I take it out as I normally just lower the motor once I launch the boat and take off from there. Again thank you.

 

[ezmobee]

Re: Engine revs high prior to going on plane.

The proper use of the trim would be to start off with it all the way down (in) until you get up on plane. Once there, trim up (out) until the boat just starts to porpoise. Then lower it a little bit till it settles in.