650 MERCURY WITH DOEL FINS

[slimeyminnow]

Ok i just bought this 15 foot larson all american with a 650 mercury. It has dole fins on the motor my problem is when it starts to plane out or at WOT water shots off the sides of the fins and the water comes in to the back of the boat.I Want to take the fins off but is held on with bolts what should i use to fill the holes. Was thinking of using jb weld.What is causing the water to shoot off the side of the fins i did try to adjust the motor but didn't help. i had the del fins on other motors i never had this problem....

 

[phatmanmike]

Re: 650 MERCURY WITH DOEL FINS

take the doel fin off and toss it in the trash.<br /><br />get smart tabs.<br /><br />yes, u can use jb weld or marinetex.

 

[Fastjeff]

Re: 650 MERCURY WITH DOEL FINS

Don't bother filling the holes (unless you want to do it for esthetic reasons). They won't bother a thing. If you do want to fill them in, chamfer the holes (vee them out) and fill with Marine Tex or equivalent.<br /><br />Jeff

 

[Kenny Bush]

Re: 650 MERCURY WITH DOEL FINS

Tossit and leave the holes.... You will be fine as stated earlier....

 

[slimeyminnow]

Re: 650 MERCURY WITH DOEL FINS

Thanks for the replys i think i'm going to just going to try to taking the dole fins off i hope this will fix the water problem.

 

[emckelvy]

Re: 650 MERCURY WITH DOEL FINS

Do you have a longshaft motor on a shortshaft boat? If the motor is sticking down too far it'll cause all kinds of spray regardless of whether there's a fin on there or not.<br /><br />I've run these planing aids on lots of boats with no spraying problems, but you have to make sure the boat is set up with the motor at the proper transom height.<br /><br />The anti-ventilation plate (the big plate on the lower unit commonly mislabled the cavitation plate) should never stick below the bottom of the keel of the boat (centerline all the way aft).<br /><br />The ideal transom height depends on the hull. Having the anti-ventilation plate 1/2" above the bottom of the keel would not be an unreasonable starting point for your boat and it certainly shouldn't spray.<br /><br />If the motor is too long the easiest way to fix without buying a new motor is to build up the transom height.<br /><br />HTH and let us know what you figure out.........ed

 

[slimeyminnow]

Re: 650 MERCURY WITH DOEL FINS

I did look at anti-ventilation plate for the problem the plate is about 1/2 inch may be an inch away from the keel....

 

[JB]

Re: 650 MERCURY WITH DOEL FINS

Above or below?

 

[slimeyminnow]

Re: 650 MERCURY WITH DOEL FINS

That would be below the bottom of the keel it's more like half inch below the transom

 

[gatorred]

Re: 650 MERCURY WITH DOEL FINS

it should be even or close

 

[slimeyminnow]

Re: 650 MERCURY WITH DOEL FINS

I'm going to try to post a pic this is not a good one...but i hope it helps<br /><br /><br /> <br /><br /><br /> http://img443.imageshack.us/my.php?image=dsc001124ed.jpg

 

[Kenny Bush]

Re: 650 MERCURY WITH DOEL FINS

You look good boss. Get that doel fin off (I think the Stingrays are better).

 

[slimeyminnow]

Re: 650 MERCURY WITH DOEL FINS

To that i hope i'm ok the doel fins kinda look small for the motor..Will take them off to see if it improves any.

 

[Kenny Bush]

Re: 650 MERCURY WITH DOEL FINS

Those old Doel'fins slide over the rib of the cavitation plate(top and bottom). The bottom portion is the part giving you trouble because it is below the cav plate. Stingrays are totally on top and cheaper too.

 

[slimeyminnow]

Re: 650 MERCURY WITH DOEL FINS

What size of smart tabs sould i look for.. I think i'm ging to stay away from the fins..

 

[scotty c]

Re: 650 MERCURY WITH DOEL FINS

keep the doel fins, all you gotta do is trim back a bit, and the spray will stop.<br />they are cheap and they work !<br />trim tabs will set you back a bunch and <br />you prolly don't need them on a 15' boat.

 

[slimeyminnow]

Re: 650 MERCURY WITH DOEL FINS

I did try triming the motor didn't do much but i' m thinking of gettting these.<br /><br /><br /> http://www.iboats.com/mall/index.cg...=835110046&**********=465870862&view_id=39283