Evinrude 4806E 4HP Weedless Prop Alternative ?


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Sep 27, 2023
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maitowoc, wi
Hello ! I've got a 4806E 4HP Evinrude with the Weedless Lower on a little 12' V-Bottom. I've only had it out once with this motor, and while it runs fantastic, it seems that it is not much more ooomph than the Evinrude 2HP that I had on it.

The weedless uses OMC # 0319004 2 Blade prop, and the prop really looks wacky. The blades only have a little lead in twist and then go really flat. The 2HP had a 3 blade on it that looked quite normal. I am curious if and how I can try a 3 blade prop on this 4HP, or at least a prop that doesn't look so abnormal. I already know that the non-weedless lower 3 blade prop is not going to be a direct fit because the diameter is slightly larger, but in pictures, it also looks like the spline side is much deeper. That rubber spline filler/adapter is the same part number, so if no one has an idea on what other prop might fit, I will probably order one and see if I can cut things to fit.

I'm not necessarily worried about weeds right now. Thanks for any help you can give !
Pretty simple. I know there were standard looking alternative 3-blade props that were definitely capable of making a difference in performance. Look around on Ebay and see what you can come up with. Do us a favor though and tell us the results if you would be so kind. Use a cell phone based speedometer app and you can see the difference. Any prop designed for the weedless gearcase should work.
Most mfgrs have a cross reference for going to a non needless prop. I agree with the lack of oomph on weedless props. My electric motor came with a needless and MinnKota recommended a replacement, said it wouldn't make much difference.....but it did !! Not in speed, but in power to move more quickly.
I have a 4hp with the regular lower unit and it does pretty good on the back of a 12ft boat, it don't get on plane but it does move me a lot faster than my trolling motor. I also have a 3hp, a newer model but that and the older 4hp are about the same power wise. I had an older 3hp, from the 60's with the weedless lower unit and it was pretty much useless unless on a super light boat with no current. I could paddle faster.
I'm not sure just changing the prop on those weedless lower units will work all that well, the thrust angle is wrong so they're rarely very efficient. The idea of the weedless prop is that it can operate nearly right at the surface trimmed up in shallow water and still produce forward thrust, but a normal prop will have too much cavitation at the surface and the wrong angle of thrust all the way down. Unless you need weedless drive, and if your swapping out the prop, that's out the window anyhow, go find a non-weedless 90 degree lower unit for it. and then run a good metal prop of your choice.
The thrust angle is not incorrect.
Trim the engine to the farthes pin hole and the thrust angle is roughly parallel to the bottom of the boat.and the gearcase sits farther back in clean water at that trim position. The standard 3-blade propeller is definitely quicker than the weedless. On a 14' Alumacraft model FD I could run around 6mph with a single 3hp on the back with the weedless so that was anything but "useless".
On my boat, when I kicked the motor all the way out, the prop was only 1/2" below the water's surface which gave me a ton of cavitation and little forward movement. The boat was 12ft Duracraft from the early 70's.
Most of the water we have here is shallow but moving, in the only lake that allows a gas motor there's a 30ft spillway and a fairly strong current leading to it. In the back creeks the water moves fast, and the 3hp wouldn't move the boat at all with the slightest headwind against the running current. It wouldn't move at all with the weedless prop.
My first time in the lake with that boat and motor I took my trolling motor as well, if I didn't I'm not sure I'd have gotten back to the dock up stream. When I swapped out the lower unit it was pretty decent even with the plastic prop it came with. It was very capable then of fighting the current and I was able to not worry about being drawn into the spill way current that runs through the middle of the lake.
Well your situation would be the exception and not the norm, wouldn't it?
OMC sold probably over a million of these little engines from around 1953 onward and they do perfectly fine. OMC engineering did not design the trim range to bring the prop within a half inch of the water surface at the end of the trim range, you can be assured of that. A 14' boat has more inherent buoyancy than a 12' boat does so there should have been no reason for the prop to be that close unless you were loaded very bow heavy. Have run bunches of these engines on various boats and at some of our antique outboard meets we have fun and hold 3hp races.
The point of this reply is to ask that we not discourage someone on a quest with a one-off exception to the norm situation. Thanks for your indulgence!
I converted mine from a weedless model to a conventional version years ago. The results were night and day. On 12ft jon boat with two people in it its does fine just so there's no current. If I get it into any serious current it has trouble making headway.
It was useless in fast moving water with the weedless lower and prop. I use the motor now a a trolling motor in the back bays and it got me home once when an impeller failed in the main motor but it was a SLOW ride home. If I was in the river, going against the flow it wouldn't have been able to move the boat against the current or wind. My 58lb thrust trolling motor actually pulls stronger in the current . I've had four of these and this one is he best one so far.


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