Trying to get rid of bow lift and get in shallower water

kungpaoshizi

Petty Officer 1st Class
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Apr 29, 2013
Messages
221
Motor and boat in my sig... Right now I *think the motor is properly positioned on the transom/PTT CMC plate... cavitation plate just above water input area is right around the bottom of the transom.. but the remainder of the engine is about a foot or 2 lower than the boat...

2 dislikes I'm having, I can go in 2 ft water, but I have to raise the motor quite high and it creates super bow lift...
This is while I'm doing like 1 mph 700-800 rpms... so the hydrofoil the PO has on the motor is useless at those speeds..

Can I trade the lower unit to a short shaft (is that even possible?) or can I bring the motor up?
I think I could probably only remount the cmc plate about 2" higher..
I was considering a jack plate, but don't really like the idea of losing controllability at high-er speeds..

Any ideas? I was putting around in 2 ft of water, I thought I had scraped bottom with the motor, but I realized it was the back end of the hull because of the amount of bow lift from having to bring the motor up far enough to not hit bottom, the boat isn't necessarily "flat" in the water...
 

BatDaddy1887

Chief Petty Officer
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Jan 18, 2009
Messages
463
Re: Trying to get rid of bow lift and get in shallower water

I don't think there is a swap out for a short shaft for that motor. I think you need to re-power with a short shaft engine. Other ideas would be put the trolling batteries up front to counter-balance some weight.
 

jimmbo

Supreme Mariner
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May 24, 2004
Messages
12,944
Re: Trying to get rid of bow lift and get in shallower water

Replace the lower unit with aftermarket jet drive assembly
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Re: Trying to get rid of bow lift and get in shallower water

pics
 

kungpaoshizi

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Apr 29, 2013
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Re: Trying to get rid of bow lift and get in shallower water

IMG_20130803_205934.jpg

I marked the top metal edge of the transom, the top left corner of the cmc plate, and the actual line from bottom of boat to level point on motor lower unit..
The engine is down level but the angle of the pic is off to see the bottom of the boat.
 

kungpaoshizi

Petty Officer 1st Class
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Re: Trying to get rid of bow lift and get in shallower water

IMG_20130803_205817.jpg

Here's another, but sure, I'll get some day pics
 

wired247

Lieutenant Commander
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Oct 8, 2011
Messages
1,557
Re: Trying to get rid of bow lift and get in shallower water

Sure, you can get a 15 inch mid and lower for a tower of power. Seen quite a few of them. Keep the prop shaft around 4 inches under the lowest point on the boat.
 

kungpaoshizi

Petty Officer 1st Class
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Apr 29, 2013
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Re: Trying to get rid of bow lift and get in shallower water

Know any good links for the towers specifically wired? (ty!:D)

Replace the lower unit with aftermarket jet drive assembly

Btw do you know of one that is compatible with the tower of powers?
 
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Chris1956

Supreme Mariner
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Mar 25, 2004
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27,036
Re: Trying to get rid of bow lift and get in shallower water

If the transom is 20" high, a short shaft motor will not work due to ventilation. You need to go to jet drive or a kicker.
 

wired247

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Re: Trying to get rid of bow lift and get in shallower water

If the transom is 20" high, a short shaft motor will not work due to ventilation. You need to go to jet drive or a kicker.

He has a 20" shaft on there now and its sitting far below what would be reasonable unless you are one of those people that likes to put as much of the motor in the water as possible. He also looks to have a jackplate installed and it is unknown whether he has that raised or not. I suspect not given that his anti ventilation plate appears to be at the keel line. Works great in ocean liners going 15 MPH but in shallow water or anything you want to go over 30 mph its a terrible way to run the motor. In any case losing 5 inches is not going to hurt him one bit.

First thing I would try is jacking that motor up to the point the prop shaft is 4-5 inches below the keel line. If its sticking way up in the air at that point...which it will be, then start looking for a 15 inch mid section.


Jet lowers are available and quite common for those TOP motors although there is no way he will be able to run one with his motor that low in the water. The jet will not work unless its basically at the keel line and his mounting is WAY to low even for a jet .


Heres a 15" mid. You'd need a drive shaft too or the existing one could be shortened.

http://www.ebay.com/itm/VINTAGE-MER..._Accessories_Gear&hash=item46117dfb1f&vxp=mtr
 
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Chris1956

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Mar 25, 2004
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27,036
Re: Trying to get rid of bow lift and get in shallower water

So by looking as one dark picture, you know his transom height? You don't think a '86 bass boat would have a 20" transom? That would be wierd, which is why I asked him to measure his transom.
 

wired247

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Re: Trying to get rid of bow lift and get in shallower water

His motor is not attached to the transom. It is attached to a CMC tilt bracket. That in itself will drop the motor 2 inches . If the CMC bracket is not in its top holes it will be too low for what he is trying to accomplish and even then it will be too high as a 20 inch TOP sits MUCH lower in the water than just about every other modern outboards especially in shallow bass boats. He basically needs a surfacing prop and a very high prop centerline. A 15 inch TOP lower puts the bottom of the lower unit at about the same location as a 20" johnnyrude or 20 inch modern Merc V6.

I get the same thing. Skooting along in the river in 100+ feet of water and then all of the sudden i look at the depth gauge and I'm skimming along in 1-2 foot of water on a rocky bottom. Not cool. To do that you have to get the motor up as far as humanly possible or you buy a few props a year.
 

kungpaoshizi

Petty Officer 1st Class
Joined
Apr 29, 2013
Messages
221
Re: Trying to get rid of bow lift and get in shallower water

If the transom is 20" high, a short shaft motor will not work due to ventilation. You need to go to jet drive or a kicker.

What's a kicker?

Otherwise I'll get those measurements and more pics tomorrow, works been crazy :(
Thanks fellas!
 

Chris1956

Supreme Mariner
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Mar 25, 2004
Messages
27,036
Re: Trying to get rid of bow lift and get in shallower water

A "kicker" is an old term for a gas-powered small outboard motor.
 
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