got a 25 horse merc i have a ??? about.

Birdhousepdx · 08-03-2009, 07:25 AM

I have a 15 foot smokercraft with a 2000 merc 25 horse big foot. i noticed on saturday when out on the willy just cruising around that from time to time the motor would rev up, kinda like on my quad when i loose traction. and it would really only do it when other boats have passed by and im going at 3/4 throtle, is this because the prop lifted from the deeper water or is there something going on with my motor. any and all help would be great just trying to figure stuff out first time boat owner you know, there is alot to figure most has been trail and era...

Maddie'sDaddy · 08-03-2009, 08:34 AM

Quote:

Originally Posted by Birdhousepdx

I have a 15 foot smokercraft with a 2000 merc 25 horse big foot. i noticed on saturday when out on the willy just cruising around that from time to time the motor would rev up, kinda like on my quad when i loose traction. and it would really only do it when other boats have passed by and im going at 3/4 throtle, is this because the prop lifted from the deeper water or is there something going on with my motor. any and all help would be great just trying to figure stuff out first time boat owner you know, there is alot to figure most has been trail and era...

Sounds like Cavitation to me, thats where a pocket of air gets in the prop area and causes the prop to spin free for a moment, I dont know the cure, maybe the motor needs to be lower in the water?
http://www.tropicalboating.com/power...propeller.html

MD

Mud Duck · 08-03-2009, 08:56 AM

I can"t tell you the problem or solution for sure. I have a kicker motor on my driftboat and it runs great, except it will lift or bounce thru another boats wake and do the same thing OCCASIONALLY. I think it may be cavitating, and lowering into the water may fix it, As suggested elsewhere. I can't however, it's a long shaft that doesnt get longer LOL. I"ve lived with it, it doesn't seem to hurt anything? Hope you enjoy the boat.

Dan Feller · 08-03-2009, 09:06 AM

I have the same motor on my 14' Zodiac. I had cavitation problems when I first installed it on my boat, lowering the motor solved it. Before you lower the motor you could fiddle with the angle of the motor trim and see if that helps.

Birdhousepdx · 08-03-2009, 02:41 PM

That what i was thinking, its a long shaft motor and the guy i bought it from have the transom built tall so it would get up on a plain fast? dont really no much about boats but it sure does catch fish though first day i got it me and the wife and buddy went on the willy down by the sellwood area after some sturgeon. The wifes first time fishing. 13 shackers and a keeper put in only 5 hours went back the weekend after same spot 2 shackers in 8 hours.... well the boat has not been aced out yet..