Difficulty in getting plane with an evinrude v8

**alexvzx** · 02-02-2018, 06:24 PM

I have an evinrude v8 (20 inch) installed in a Boston whaler (19ft) outrage without a jack plate. This is the first time that this setup was tested because the boat and the engine was recently restored. The engine is set as low as possible. When I push the throttle down the boat starts to plane, however, at 3000RPMS the propeller is not engaging anymore and the engine starts to reverb like it is neutral. The propeller is a raker 26 pitch, some people mentioned that maybe the pitch is not allowing to get a grip, other mentioned that the engine is too high (that is strange because I saw some whalers in the internet with the engines set higher than mine), other mentioned that if I add a setback of 6 inches will solve issue, others mentioned that if I install a Stabilizer Plate will eliminate the issue. I check the propeller and is working fine, no issues with the bushing. Here is a picture of the lower unit and the bottom of the boat.

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What I am trying is not to spend some money in things that will not solve the problem. Any suggestions will be appreciated.

**jimmbo** · 02-02-2018, 07:20 PM

The V8 does have tremendous torque and the prop may just be too small of a Diameter to stay hooked up. A RAKER is a vented prop, try blocking the vent holes. More cup and Rake might be needed too. Here is one place a 4 blade might actually be of some use. Contact Mercury Propeller, they make some of the best props on the market. You have the motor mounted high enough on a boat without a pad, that you may actually need very a high performance prop to keep it hooked up.

Of course the rubber slip hub might be doing just that, slipping. 300hp on a 19ft is a lot, even a Whaler. Just curious, what is the Whaler rated for HP wise?

Can you post a pic with the engine trimmed out to where the Anti-Ventilation plate is parallel with the hull bottom. That would show the engine height better

**oldschoolnc** · 02-02-2018, 08:23 PM

Looks like the boat as a 25" Transom. Is that the case? If so, a 6" setback would help, but you would not need any more elevation. You need a 28p bad ass prop, four blades are real nice for hooking up and staying hooked up in turns...... Just my opinion...

**phillnjack** · 02-02-2018, 08:25 PM

you just need a bit of setback, about 8 to 10 inches should be fine. personally I would look for a 8 inch or 10 inch jackplate.
as it is its too close to the boat and getting miles to much air.. it realy is that simple.
your transom is obviously a 25 inch transom. ... with a nice setback you will be straight onto the plane and getting great top end speed with that motor.
no prop is going to work with the motor at that height right next to the transom.

once on the plane you might be able to go up a bit more and realy fly. .

**alexvzx** · 02-02-2018, 08:38 PM

I was taking in consideration a jackplate of 6” set back. However, I was wondering if the jackplate will case that engine be higher even in the lowest position. If the setback will solve the issue, then I would be able to use the same prop.

**vnemous** · 02-02-2018, 10:03 PM

I would think at that height and closeness to the transom the hull is actually pushing water away from the prop the faster you try to go. You deff have to go back some.

**skiboater** · 02-02-2018, 10:11 PM

What is the diameter of the raker?

**alexvzx** · 02-03-2018, 06:39 AM

Is a 14.5x26. If I install a jackplate with a 8" setback the engine will be little higher due to the design. Would that affect or the setback will compensate.

**skiboater** · 02-03-2018, 08:47 AM

What is the angle on your transom?

**phillnjack** · 02-03-2018, 09:33 AM

it is not an angle problem, its a 20 inch motor on a 25 inch transom. needs to go back.. just make a setback and see if it works, then when it does go buy a real nice one or make a real nice one.

lots of people have put Gill brackets on whalers with big motors.
this page link below will help you see what others have done also see what Boston whaler made too.

http://continuouswave.com/whaler/ref...eBrackets.html

.

**alexvzx** · 02-03-2018, 07:13 PM

https://bobsmachine.com/product/mj8-...te-300-hp-max/

Hope this will solve the issue. The link is for the jackplate that I am checking.

**FMP** · 02-03-2018, 07:33 PM

Hydraulic, take full advantage and lower it in heavy seas. Plus it looks cool at the dock.

**oldschoolnc** · 02-03-2018, 08:15 PM

Nice Bracket, but for your app I don't think the 2.5" min lift will help your situation much. On calm water with right prop might be ok, but in a swell it might ventilate excessively. Can you re-drill your transom holes 3" lower? Then use the plate ur looking at and have some adjustability if desired. Just a thought....

**phillnjack** · 02-03-2018, 08:31 PM

he wouldn't be able to have the steering right, the cable would have to bend down.
he just needs 8 inches of setback, but the problem is going to be a weight issue, the further back it goes more leverage and more of
an arse drop when stationary. those v8 motors are not light ha ha