1984 Stern drive

[dad_t]

Hope you someone can give me a hand. I just got a seaswirl with a 3.8L motor the boat runs great. The only problem that I have with it is at low speeds the boats stern drive seams to walk from right to left and it is hard to keep in a straight line. As it gains speed the problem no longer there could it be out of line or is there an adjustment to be made? Is there a manual that can help with solving this problem? The model number from the stern drive is a OMC #983159.<br /> Thank you in advance

 

[twwmm]

Re: 1984 Stern drive

Ive heard this called the drunken stagger.<br />I had volvo duoprop that did a similar thing at low speed it was hard to keep in a straight line. i think it is more to do with the boat design if there is not much keel theres not much to keep the line as speed increases what keel is there becomes more effective and more control. I found that when there was a wind from the side it would stay straight, so i dropped one trim tap fully and the other up to give some drag to compensated against, this helped must change the thrust angle. I could sort of liken it to balancing a broomstick on the plam of your hand (vertcally) the bottom moves all over the place while the top stays steady. probly also to do with weight of boat etc etc. It did come good at about 1400pm. There is a trim adjustment on the leg but this is usually course adjustment at high speed and will be off left or right but not both. By nature a prop will tend to paddlewheel at very low revs in the direction of rotation but again only one way.<br />Cheers

 

[Trent]

Re: 1984 Stern drive

Bet this is a V-hull boat? If so...normal (boat design as was said above)

 

[dad_t]

Re: 1984 Stern drive

Thank You for the help, and yes it is a v-hull boat.

 

[DJ]

Re: 1984 Stern drive

Fun in the sun,<br /><br />You are experiencing "V-Hull Wander". Perfectly normal. The phenom. tends to make the operator of the boat overcompensate by adding to much corrective steering input, thus exaggerating the situation.<br /><br />There is no 100% solution. Sometimes, a fin on the cavitation plate (Doel Fin, Stingray, etc.) helps. Also, trim tabs, as mentioned above, can be helpful.<br /><br />Best to just learn to try to not overcompensate.