Help with tuning my 1455 roughneck

Joined
May 15, 2011
Messages
21
Hi

I am really new to boating and would like some help if possible.

I have a Lowe 1455 roughneck powered by a 25hp mercury seapro. It has a 20 inch transom and the motor has a 22 inch shaft. I have 2X 27amp batteries at the back of the transom. One is for my trolling motor and the other one is for my light, bilge pump, fish finder and back up trolling motor power. I myself weigh 235lbs. I usually go out with an extra person adding another 190lbs sitting about in the middle of the boat. I went out today and the water was like a piece of glass and I was getting a speed of 22MPH WOT. Motor was trimmed to the 3rd hole. I found its teh best for getting up on plane. I have a aerofoil on the motor and I get up on plane fairly quickly but would like to get more top end and better fuel efficiency. The prop on it is a 9.9 dia with a 11 pitch. I have been reading up on the jack plates but I would like to know if raising my motor 2 inchs will help that much? I hate to drill holes in the transom for nothing. Also, do I have the right prop? I don't know what RPM its running at as I have a no gauges. If I am alone in the boat I get about 25-26MPH. I have spent allot of time reading other post but would like to hear suggestions for my setup.

thanks!
 

just_crsn

Seaman Apprentice
Joined
Feb 29, 2008
Messages
49
Re: Help with tuning my 1455 roughneck

Those are good numbers for both . Not sure you will get any better out of a 25hp. Your boat is fairly heavy ad its a 14fter, which will take a little more to plane out compared to 16ft. I would not spend to much money.....you will not gain much on the top end...maybe 2mph. I have a 25 hp on a 16ft lowe rivited and get ( by myself) 29 mph with a boat half your weight.
 

lncoop

Vice Admiral
Joined
Apr 18, 2010
Messages
5,147
Re: Help with tuning my 1455 roughneck

+1. Not reasonable to expect much more out of your rig. If you want to experiment with having the motor higher you can run her with a piece of square tubing under the bracket and see how she does, but I wouldn't burn too much time or money on it. Good luck and welcome aboard.:cool:
 
Joined
May 15, 2011
Messages
21
Re: Help with tuning my 1455 roughneck

Thanks for the input guys. I am going to try raising the motor to see how that works. I wanted to pick up a spare prop so I may get a 13 pitch to try. I am going to play with the weight distribution as well. I will move my spare battery to the front and same with my gas can.

22mph is good enough for me but I took it up river 15 miles and that is what got me thinking more speed.
 

pootnic

Chief Petty Officer
Joined
Aug 11, 2007
Messages
447
Re: Help with tuning my 1455 roughneck

Have you ever tries it without the foil?
Is the foil out of the water when planed?
Thats a pretty wide 14' boat,those numbers seem to be close...
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Help with tuning my 1455 roughneck

Here is some info from another forum I posted in. This boat doesn't have any decks, batteries or trolling motor, yet. When I do, I expect to drop the prop pitch down.

===================================================================

Calculated Prop Slip on Jon Boats - What is a reasonable number?

I picked up a new project boat a little while ago. It is a DMI 1648 mod-vee jon boat (welded seams, but rivited supports), with a '98 25HP Merc 2 stroke.

With the merc prop (13P), I am getting 5600 rpms (wot rpm range 5-6K) with a gps speed of 26mph. This is two adults plus some fishing gear. Manual trim settings were tested, and best seems to be parrellel with bottom, but about 1.5" below. Raised it 0.75" with no measurable improvement. Water still going over top of cav plate. I cant raise it any more without drilling holes in transom or using a jack plate.

Using a calculator, and specified gear ratio, I get a 16% slip. That seems a little high, but this is my first jon boat. Speed seemed reasonable to me, based on semi-v and v experience. I have seen some people reporting speeds of 30-31mph with similiar boats and motor combos. Many people don't seem to use tachs on small motors, that and not having the engine gear ratio, kept me from being able to make a comparison. BoatTest.com doesn't seem to test these small combos, either.

My next testing will be with added weight to make sure I will still have decent performance after adding trolling motor, battery, front and rear decks, etc.
 

DonHof

Petty Officer 1st Class
Joined
Oct 19, 2009
Messages
318
Re: Help with tuning my 1455 roughneck

I have a 14.75 Lund V bottom. It has a 30Hp, it has floor and side console.
With the wife and I, I can get 25 mph. Has the same prop as yours.
Takes a little bit to get on plane but it dose.
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Help with tuning my 1455 roughneck

I checked some specs on your boat. Yours is 200lbs heavier, with 6" wider hull, but 2' shorter, than mine. I'd take the foil off and try adjusting trim again. The hole shot may suffer a little, but you won't have the drag at higher speeds. (cav plate is below bottom of boat) If you are just using the clamps, you can get 0.75 - 1" higher by blocking up motor.
 
Joined
May 15, 2011
Messages
21
Re: Help with tuning my 1455 roughneck

You think I should change the prop to a 13 pitch or keep the 11? I can't really block the motor up on the transom cause of the clamps. The inside of the transom is not flush. For some reason when they did it there is a 1/8th lip about 1 inch from the top of the transom. SO the clamps will not be flush if I raise the motor. I am scared the motor ends up on the bottom. I ordered a min jacker at bass pro and I will mount that and try it. I will also try removing the foil. I will hold off on the 13 pitch prop until further testing.

Thanks



I checked some specs on your boat. Yours is 200lbs heavier, with 6" wider hull, but 2' shorter, than mine. I'd take the foil off and try adjusting trim again. The hole shot may suffer a little, but you won't have the drag at higher speeds. (cav plate is below bottom of boat) If you are just using the clamps, you can get 0.75 - 1" higher by blocking up motor.
 

Mi duckdown

Commander
Joined
Apr 14, 2007
Messages
2,575
Re: Help with tuning my 1455 roughneck

rougneck Pics would be helpfull, of your motor setup as is.
from the transom both sides. inside and out.
Motors are 15 inch or 20 inch. something is not right.
Show pics of lowerend in relation to the bottom of transom. side shot/pic
 
Joined
May 15, 2011
Messages
21
Re: Help with tuning my 1455 roughneck

You are right pics would help but as for the motor it is a 22 inch shaft. The regular merc engine is 20 but
The seapro is 2 inchs longer. Look it up on specs. My transom is 20 inchs.
 

5150abf

Vice Admiral
Joined
Aug 12, 2007
Messages
5,808
Re: Help with tuning my 1455 roughneck

Getting the engine up and out of the water will help alot, looked up your baot and with the lay out you have moving weigh forwad is going to be achallenge but that would be the second biggest thing you could do.

With you, gas, the engine and 2 batteries all in the back of the boat it way out of balance so if you can figure out how to move anything heavy forward that is free speed right there.

I agree with holding off on the prop until you try everything else, just raising the engine will do alot.
 
Joined
May 15, 2011
Messages
21
Re: Help with tuning my 1455 roughneck

here are some pics of the motor and boat. I took one of the batteries and put it in the front cargo on the left and I will put my gas can in the middle of the boat but right up againts the front storage. That should take some weight out of the back right there. The next thing is I am going to get on the treadmill and lose 40lbs lol..

If you guys need more pics let me know. I will post my results tomorrow as I am going out again.

Thanks for all the help.

http://s710.photobucket.com/albums/ww101/mochacon_2009/roughneck 1455/
 

pootnic

Chief Petty Officer
Joined
Aug 11, 2007
Messages
447
Re: Help with tuning my 1455 roughneck

That mini jack plate,could be the ticket.
Looks like you could raise the outboard up atleast acouple inches.
 
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