slow islander

[xltier]

does anyone know if i have foam in the hull of a 1986 starcraft islander 221.took out a 4cl and put in a v6 -..still struggels to get going.if so is it hard to remove if its saturated.

 

[oldjeep]

does anyone know if i have foam in the hull of a 1986 starcraft islander 221.took out a 4cl and put in a v6 -..still struggels to get going.if so is it hard to remove if its saturated.

When you put in the V6 did you also replace the outdrive and prop? 4Cyl uses a different gear ratio than a 6 cyl

 

[xltier]

I used a gen2 transom assem. and outdrive out of a 4cyl.i have a 14.5 x 19 prop on it.i also have a 151/4 x 15 spare.just seems like the bow wants to be up all the time.

 

[oldjeep]

Well then you did it wrong. You put a 1.93 gear ratio on instead of a 1.81. What was the engine/drive combo originally?

120 & 140	4 cylinder	1991 thru present	1.93 / 20-24
175 & 4.3	V-6	1991 thru present	1.81 / 17-19

 

[xltier]

I guess I Assumed that the lower gear ratio would just wind up more and I could go with a higher pitch prop.plus I want to mput a fiberglass roof on with rocket launchers.

 

[xltier]

the engine came fro\m a 1989 4.3 mercruiser 19ft. boat.i think a stingray.the transom assem and outdrive came from a 2005 bowrider.17ft.not sure of brand.

 

[airshot]

Easiest thing to check is have it weighed, if your a few hundred pounds heavy then you have a water logged hull. All the flooring must be removed to get the old wet foam out. Numerous rebuilds in that forum area to show you what your looking at. Could also be the weight distribution inside your boat...nothing will be right until you get the correct ratio and prop and go from there. I have an 83' Islander with the 140 hp 3.0 and she will do 34/35 mph by gps with 2 adults with all the fishing gear, full tank of fuel and a kicker motor. I have my weight distributed well as she planes fairly quick.

 

[xltier]

so they are filled with foam.?

 

[Bondo]

Ayuh,.... They are,....

 

[Watermann]

I did a conversion to 4.3 as well. If the boat has been left to the elements over the years and rained in while bow down with the plug in then the pour in foam could be saturated adding weight. You do need the correct upper gear case ratio like said.

What HP is the 4.3? and did you check the health of the motor with a compression check?

 

[Alumarine]

Does your tach work?
You should be able to easily over rev that with those props.

Even with the wrong ratio if you put on a 21 or 23 pitch prop it should get up on plane. Will probably still be able to over rev though.

Unless of course you're way overweight.
You do have the motor trimmed all the way in?

 

[xltier]

thanks bondo---I think I am marc.ill order a new one.----thanks waterman yes the boat that it came from was a friends and it went very well.got crashed thou.i think I need to check for wet foam and move some equipment forward somehow.everything is screwed to the transom.maybe some trim tabs after I check the foam.