2 issues: Boat "rocking" and Motor not long enough?

[Hukeedo]

I have a 1957 Glaspar Avalon 16 ft walk-around V-hull Fiberglass cruiser. It has a 50 hp merc 500 I put on it. The Boat seems to "rock" alot when I enter the boat, and I have to constantly have people equal the weight out or it leans alot.
Also, The motor seems to sit high in the water, it jumps a bit like it's coming out of the water. The top of the cav plate at WOT is exposed some and throws water out the sides. The transom is about 22 inches and the motor is a long shaft, so I believe it's the right shaft size. It's peeing water good, so it's getting water. Anyone have any ideas on these two things and how to correct them? I'd like to get this boat more stabile in the water side to side.

 

[allpoints360]

Re: 2 issues: Boat "rocking" and Motor not long enough?

Look into some trim tabs. This might help both issues.

 

[Bondo]

Re: 2 issues: Boat "rocking" and Motor not long enough?

I'd like to get this boat more stabile in the water side to side.

Ayuh,... It's a 16' boat,.... Get a Bigger boat...

 

[Jeep Man]

Re: 2 issues: Boat "rocking" and Motor not long enough?

With a 22" transom, you may have to look at an extra long 25" motor.

 

[tmcalavy]

Re: 2 issues: Boat "rocking" and Motor not long enough?

Rocking is normal in a sharp, deep V-hull. If your cav plate is even with the keel or within an inch or so, you should be all right...as long as it gets water to the pump intake at speed. When it's set too high, the prop bite will slip and the boat will lose forward momentum. To set it deeper, you can A.) cut out some of the transom top, or B.) make/install a jackplate for your motor. Tashasdaddy has a good diagram on the forums showing how he did this. What year is your Merc 500? I had a 73 on my first boat and it was a real champ.

 

[ezmobee]

Re: 2 issues: Boat "rocking" and Motor not long enough?

Takes some pics of your transom from the back and from the side. We'll be able to tell you if your motor is too high or too low. I would also be interested to see how much deadrise (how deep the V is) on your boat because I also have a 16' but it is fairly flat on the bottom and I've always been really impressed with how stable it is. My 230 lbs can step squarely on the gunnel getting in or out and it barely rocks from side to side.

 

[ziggy]

Re: 2 issues: Boat "rocking" and Motor not long enough?

i went from a 72 tri hull to a 75 v hull. so the listing was new to me. my buddy's newer v hulls don't seem near as effected by listing due to weight distribution. but my old boat sure does. i always have to adj. load evenly or i list to one side or the other... might be nature of the beast of old technology.. i also rock and roll a lot more than they do out in the surf. so far, only thing i've done about it is get used to it. i don't feel there's anything wrong with my boat..

 

[Hukeedo]

Re: 2 issues: Boat "rocking" and Motor not long enough?

I'd like to get bigger boat but all my time and money is in this one, so it's what I got, but I love it just the same.
I had a Tri-hull and went to this V hull design, so the lsiting is new to me and maybe I will have to get used to it. But, regardless, I am going to install Trim Tabs before next boating season.
I thought about cutting the Transom down, which on this boat would be a cake job. I only need maybe 2-3 inches and i think it would A-Ok. Getting an extra long shaft motor is not an option, first, they are very hard to find in my searches, and the motor I have on there now is a 72 merc 500EL 50 hp, fantastic running motor,fast and I don't want to part with it. If I dropped the motor down some, I'm thinking it may improve the stability a bit? What do you think?
I will post some pics of the motor position so everyone can see the cav plate position. As soon as it stops raining, I'll do that.
Thanks for all the replies guys and the great info.

 

[ezmobee]

Re: 2 issues: Boat "rocking" and Motor not long enough?

Yeah definitely get us the pics. But maybe a jackplate with a good amount of set back would allow you to run the motor at it's current height.

 

[jhs5150]

Re: 2 issues: Boat "rocking" and Motor not long enough?

I'd like to see pics of that. Those 50's 'glass boats were COOL!

 

[BLU LUNCH]

Re: 2 issues: Boat "rocking" and Motor not long enough?

1950's 16 footer needing 25 inch shaft? Something is not right the way the motor is mounted.......

 

[Hukeedo]

2 issues boat pics

2 issues boat pics

I have attached some pics, hope the motor shot is enough to see the position. the others are just other shots of the boat. Since these pics, the gray top has been added. Hope the pics show up on here.
Thanks.

 

[ezmobee]

Re: 2 issues boat pics

Re: 2 issues boat pics

Those aren't the best angles. But from the top pic, it looks like there's a good chance the motor is too high.

 

[BLU LUNCH]

Re: 2 issues boat pics

Re: 2 issues boat pics

Those aren't the best angles. But from the top pic, it looks like there's a good chance the motor is too high.

I agree, it sitting like 3 inches too high at least.........
Take a picture from inside at the mount and one from the side focused at the mount and transom..............

 

[ziggy]

Re: 2 issues: Boat "rocking" and Motor not long enough?

i think engine is to low and needs to be raised. but i've already been wrong once tonight...
the anti vent plate looks below the bottom of the boat. i thought it was supposed to be level or perhaps a shade above the bottom of the boat... maybe i don't understand..

 

[ezmobee]

Re: 2 issues: Boat "rocking" and Motor not long enough?

Ziggy, the camera angle is from a good bit above the keel. It actually looks close to perfect in the picture. But I bet if we got a shot from down on the level we'd see it was too low.

 

[Hukeedo]

Re: 2 issues: Boat "rocking" and Motor not long enough?

That is a bad pic of the motor position guys, i will take new ones from better angels and post . thanks guys.

 

[Hukeedo]

Re: 2 issues: Boat "rocking" and Motor not long enough?

Here is a better pic of the Motor and boat bottom. Would really like to know if the position is correct. I think it should be lower, but not sure.

 

[Hukeedo]

Re: 2 issues: Boat "rocking" and Motor not long enough?

Woul dthe motor being too high on the transom, cause it to be unstable, listing sideto side?

 

[tmcalavy]

Re: 2 issues: Boat "rocking" and Motor not long enough?

It's a couple of inches too high IMHO. Question is...do you want to hassle with trimming the transom down and remounting the outboard? An offset jack plate might be a simpler solution.