12' aluminum v-hull won't plane

[smurphys1982]

The original motor was a 8hp evinrude, so I upgraded to a 15hp evinrude. Still no luck. Could it be extremely bad luck and I got stuck with 2 bad motors? They both seemed to have ran perfectly fine. Or is it a weight factor? The old man that owned it before me outfitted it with 3/4 plywood front and back, carpet, two batteries and and two wooden boxes/compartments the one has the batteries the other contains misc items. Should I strip it and see how it does? Am I dealing with a weight factor or a motor issue?

 

[jigngrub]

Re: 12' aluminum v-hull won't plane

It may be both, post some pics of your boat. Your motor may not be at the right height on the transom (cavitation plate too low).

We need to see your transom, the bottom of the hull, and the foot of the motor in the running position.

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

I made sure the shaft was the right measurement, as far as the cavitation plate in realitionship to the bottom of the boat. It's a short shaft motor

 

[tx1961whaler]

Re: 12' aluminum v-hull won't plane

Is it running on both cylinders?

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

I think it would be pretty obvious if it weren't, besides what are the chances of both motors lacking a cylinder

 

[jigngrub]

Re: 12' aluminum v-hull won't plane

What trim position do you have the motor in? If it isn't already, set the motor down in the lowest trim position.

Read this and see if it helps:
http://www.outboard-boat.com/index....boat-systems-and-set-ups&layout=blog&Itemid=1

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

Nothing I've tried all posistions. I'm wondering of its a weight issue, from what I described earlier does it sound like that could be the issue?

 

[tx1961whaler]

Re: 12' aluminum v-hull won't plane

I think it would be pretty obvious if it weren't, besides what are the chances of both motors lacking a cylinder

It's really not obvious at all. A motor will run smooth and idle well with only one cylinder firing, but just has half of the power.

 

[jigngrub]

Re: 12' aluminum v-hull won't plane

Nothing I've tried all posistions. I'm wondering of its a weight issue, from what I described earlier does it sound like that could be the issue?

Take all the added stuff out and see how it does then, if it still doesn't plane out it's either your motor or operator error.

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

I think it's running at full power

 

[pootnic]

Re: 12' aluminum v-hull won't plane

You said what it isn't doing but what is it doing?
Sound like the rpm's are getting up there?
Is it plowing through the water or is the bow high in the air?
What size prop and is it in good condition?
How about the bottom of the boat any big dents,especially right at the stern where the water hits the prop?
Like you said could be a weight issue though...

 

[Solittle]

Re: 12' aluminum v-hull won't plane

I think it's running at full power

If it were running full power you would be up on a plane very easily with a 15. To put it bluntly yur motor ain't runnin right.

I have a 12'er with a 1975 9.9 and it gets me at 200 lbs + hefty wife on plane.

 

[jigngrub]

Re: 12' aluminum v-hull won't plane

Post pictures of your boat, motor, and propeller!

We really can't help you anymore unless we can see what you're dealing with.

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

Will do, check back tomorrow and I'll have them here

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

May be a dumb question, but, how on earth do I post pictures lol I'm new to this forum and a new boat owner. Keep in mind that purchasing a boat (although nothing extravagant) was one of the best investments me and my family have ever made! The one problem we've discovered, is coming up with the funds to go to the lake every weekend lol

 

[5150abf]

Re: 12' aluminum v-hull won't plane

I am in the "motor isn't running right" camp, even with all the mods the PO did it should still plane out pretty easily with a properly running 15 horse.

Have you ever checked the engine smurphy, if so what did you do and find.

If could be a simple as a dirty carb,as tx1961 said, it is hard to tell if a 2 stroke is hitting both cylinders at or near idle.

My first boat was a 12' jon with '69 9.5, I had the battery gas ect ect and my 180 lb buddy in the boat and it would plane pretty easy, my point being, make sure the engine is 100% before you tear your boat apart

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

It all checks out good, the carb has been rebuilt, the cylinders are around 90 psi, spark at both wires etc also the chance of having two bad motors is pretty slim. It has a lot of weight

 

[series60]

Re: 12' aluminum v-hull won't plane

The original motor was a 8hp evinrude, so I upgraded to a 15hp evinrude. Still no luck. Could it be extremely bad luck and I got stuck with 2 bad motors? They both seemed to have ran perfectly fine. Or is it a weight factor? The old man that owned it before me outfitted it with 3/4 plywood front and back, carpet, two batteries and and two wooden boxes/compartments the one has the batteries the other contains misc items. Should I strip it and see how it does? Am I dealing with a weight factor or a motor issue?

My 1970 14' MirroCraft aluminum flat gets it when I turn up the wick on my 1959 18hp Evinrude. Boat empty might weight 120#s. With anchor, 6 gals fuel, 78# outboard, trolling motor and deep cycle battery, tackle, iced cooler and me the whole thing probably close to 500#. I would hit 20mph on the gps, (3500' elevation lake) that is until the ole' original prop hub started giving up the ghost. Slowly she started loosing speed with constant power. Back out of it and she drops off plane as normal. Could putt-putt around the lake fishing and then heading to the ramp - she wouldn't get close to plane.

Check the prop hub to see if it's slipping.

​

 

[smurphys1982]

Re: 12' aluminum v-hull won't plane

How do I post pics?

 

[series60]

Re: 12' aluminum v-hull won't plane

How do I post pics?

From Don:

First of all, you have to have your picture "On The Web" one method of doing that is to use a free service like http://www.photobucket.com/ to post your pictures. <br />Then you can use the URL from the picture and use the image button for posting, or just copy and paste the link and we can click on it.