Probably a dumb question

[mikeregas]

I am sure that this is a dumb question or at least a hmmm one. I have a 90 hp Mariner on a 16ft Action Craft. I have had the boat for about 9 years and I have never replaced the prop. I have noticed that my boat is slowing down and now I can barily get it on plane, but once on plane the boat seems to go just fine. I know that my hole shot is gone. Is it possible after all these years that I have worn down the diameter of the my prop or is it a motor problem? By the way it is a SS prop.

 

[LORDY611]

Re: Probably a dumb question

Just a WAG but I doubt SS is wearing down enough to effect anything. My suspicion is that the 'ole barge is slowly gaining water weight.

 

[Dhadley]

Re: Probably a dumb question

We need to clarify a couple of things so we know which direction to go. You mentioned the boat is slowing down - we'll assume you mean top end - but then you say once it gets on plane it goes fine. Do you mean the motor runs fine, the boat is just slower?

You say you can barely get it on plane and the holeshot is gone. When you try to jump on plane does it vent a lot and take longer to get on plane or does the motor struggle to get up the boat on plane without the prop venting?

Boats always get heavier with age for all sorts of obvious reasons. If the motor is fine and the set up wasn't maxed out 9 years ago and as it's gotten heavier you may have simply dropped out of the power curve. Yes, ss props wear. You will lose diameter and cup with time. The blades will indeed flex slightly.

 

[steelespike]

Re: Probably a dumb question

As said from your description I also suspect absorbed water in the boat.
You may want to check the compression and be sure it is running on all cylinders.I suspect boat is quite old You might observe the way it sits in the water if it has gained enough weight to affect perfprmance it will be sitting low possibly listing a little.you could also remove the extra gear and weigh the boat I couldn't find Action craft on the net so don't have a dry weright.
but you may get an idea if its seems over weight.

 

[mikeregas]

Re: Probably a dumb question

Well the boat is doing all of the above, loosing or lost the holeshot and lost top-end speed. I have been noticing that for a couple of years though. The boat is nine years old and I have, lets say gotten my money worth from this boat and motor. There are several nicks in the hull, but nothing major. I am not sure where to start and that is why I am asking you guys for all the help that you can give me.

 

[mikeregas]

Re: Probably a dumb question

The top end loss is nothing major though, however the holeshot is gone for the most part.

 

[Dhadley]

Re: Probably a dumb question

The holeshot is gone but in what way? Is it just slow to get on plane like the motor is laboring or does the prop break lose & the rpm goes way up and then finally grab again as it gets on plane?

 

[mikeregas]

Re: Probably a dumb question

the engine is laboring I guess, the rpms do not go way up. It just revs up slowly and slowly gets on plane, then it gets up to speed fine once it is on plane. The hubb is not spun.

 

[steelespike]

Re: Probably a dumb question

Water can get in the boat from rain or snow and can seep in right through the hull.Sometimes a glass boat the fiberglass breaks down.Water is absorbed
into the flotation foam under the floor and in worse case can be absorbed into the fiber glass.If you think its worth your time pull up the floor and check things out.Sometimes its just years of rain and snow absorbed in the foam
pull it out and check the stringers and transom might be able to just replace the foam.