Trim and Prop Questions - 18' Bass Boat

[alexalee]

Hello everyone, Im a new owner to a bass boat (but not boats in general) . I have a 18' -1984 Hydrasport with a 80's Merc 1150.

Ive had it on the water now several times, the first time It was just me and my son, probaly a combined weight of 200lbs for us.. and very little gear. Empty livewells, a full tank of gas and 4 batterys in the back. This first time it blasted acrossed the water and got to plane right away.. very smooth ride. The prop is a bit banged up from the previous ownwer so I Decided to get a new one, This prop has no identification on it whatsoever. But the previous owner included a newer prop that was also banged up..and looks very close to this current one..and is identified 13.25, 17pitch. But I cant confirm the 2 are the same since they are different brands.

What I got as the new one is a 4 blade Solas Rubex with 19 for the pitch. I had seen similar setups on youtube using the same prop I figured I couldnt go wrong. What I got was at the hole shot seemed like it wasent grabbing water like the previous prop..it took alot of power to get out of the hole, once It got to plane it started porpusing badly no matter how I trimmed it. But at this time I also had my mother and son with, and the rear livewell filled. The water was moderate..

I want to get the correct prop for this boat so Im looking for guidance, I Can post up a pic of the props I have. And dig up any information available if someone is willing to help.

Also..
I went back to the prop that was originally on the motor ..and this past weekend it was very windy and choppy water.. I trimed the motor all the way in and I was still bouncing in waves that were only 6-12" high and it felt a bit sketchy but it handled them. I feel it should have handled them better, since my old 16ft alum crestliner with 25hp motor would cut through that stuff no problem.

Here is a picture of the trim settings on the motor

Should the pin be lower? it doesnt look like it has ever been moved lower. Im afraid to do this as I dont know what will happen. Also When I trim the motor up..say to fish shallow waters with the trolling motor.. it will eventually sink back down after 15-20min.. Should it do this? Normally with hydraulics this would be bleeding off caused by a bad seal in a cylinder or pump I believe.


Thanks for any help

 

[Texasmark]

Re: Trim and Prop Questions - 18' Bass Boat

I think your Solas was just the opposite. With 2" more pitch and an additional blade, you are grabbing too much water and lugging the engine in the hole producing sloppy performance and an engine that doesn't like it.

A live well full of water can do funny things to your trim. Don't expect the same results as dry. Four batteries right in front of the transom along with gas is a bad enough load back there then adding the live well. No wonder you were porposing.

Porposing is caused by the engine being too far out for the speed. To stop porposing you reposition the load, putting more in/toward the bow, tuck the trim in till it quits, or speed up till it quits.....simple as that for a simple answer....no hull hook and all that.

If your trim leaks down as you say, obviously your seals are leaking and cannot even keep the engine up. When you hammer down on the throttle, the pressure on these weak seals is probably an order of magnitude higher so it just gives up and goes down to the tilt pin setting (which you showed us) and that is where it stays. Not seeing everything else, your pin seems to be in a good spot and you shouldn't get porposing at that low of a position per se....but as I mentioned above, you have a lot of stern weight to overcome.

HTH,
Mark

 

[tommy8604]

Re: Trim and Prop Questions - 18' Bass Boat

I would agree with Texasmark, just the four batterys in the back of the boat is alot of weight. i had a ranger with only two batterys and if you put three in it, it would take a year it seemed like to get on plane. sometimes i would even have to send someone to the front to get it to plane and that was with the same motor you have. A 19 pitch shouldnt be a bad pitch for you but if you know you are leaking down i would suggest getting your seals fixed. With that much stern weight it would help if you could trim all the way down and also when your leaking down you will never be able to hold the trim you need at speed.

 

[alexalee]

Re: Trim and Prop Questions - 18' Bass Boat

2 of the batterys are Large Deep cycle marine batterys (same size as semi truck batterys) I got them linked together for 24vt on the trolling motor. the other 2 are standard size marine batterys (size of a car battery). I have room in the front to make a compartment.. Im thinking I can place the 2 larger batterys linked for 24vt in the front/center, then place the 2 small ones one on each side of the rear to even it out. This should help right? Its alot of work to do. I guess I was missinformed long ago.. I was told to keep the weight out of the front of the boat and more towards the center/rear


The motor doesnt leak down right away.. Id say 15-30min it will start to settle down. When im at WOT in the boat and trim it up I havent noticed it settling down.

 

[Texasmark]

Re: Trim and Prop Questions - 18' Bass Boat

2 of the batterys are Large Deep cycle marine batterys (same size as semi truck batterys) I got them linked together for 24vt on the trolling motor. the other 2 are standard size marine batterys (size of a car battery). I have room in the front to make a compartment.. Im thinking I can place the 2 larger batterys linked for 24vt in the front/center, then place the 2 small ones one on each side of the rear to even it out. This should help right? Its alot of work to do. I guess I was missinformed long ago.. I was told to keep the weight out of the front of the boat and more towards the center/rear


The motor doesnt leak down right away.. Id say 15-30min it will start to settle down. When im at WOT in the boat and trim it up I havent noticed it settling down.

Since your TM is in the Bow, moving your main TM batteries forward (and shortening the interconnect wiring) to equalize a porposing problem seems like a logical choice if it affects nothing else that bothers you.

On the trim, it's your boat and I only know what I was told. 30 minutes isn't that long....a week maybe, but 30 min??? Still, if it does bleed down, it goes to the tuck in state which lowers the bow and reduces the tendency to porpoise so that may be a moot point.

Mark

 

[tadams55]

Re: Trim and Prop Questions - 18' Bass Boat

I don'tknow if you got yours figured out nut I have a Tide Craft with 85 HP Evinrude and it seems to not want to plane as well. I have put the motor all the way down and it seems like it does not want to gain speed, when it does i can trim it up and it helps but still does not seam right. This is my first boat that has trim on controls so it is different. Anyone got any suggestions.

 

[steelespike]

Re: Trim and Prop Questions - 18' Bass Boat

You should post your own Thread. There is red tab for a new thread at the top of the prop forum.
Get us the prop size (near the base of the blades or under the prop nut) the wot rpm and gps speed lightly loaded.
Get us the size,weight and year of the Tide Craft.

 

[steelespike]

Re: Trim and Prop Questions - 18' Bass Boat

2 of the batterys are Large Deep cycle marine batterys (same size as semi truck batterys) I got them linked together for 24vt on the trolling motor. the other 2 are standard size marine batterys (size of a car battery). I have room in the front to make a compartment.. Im thinking I can place the 2 larger batterys linked for 24vt in the front/center, then place the 2 small ones one on each side of the rear to even it out. This should help right? Its alot of work to do. I guess I was missinformed long ago.. I was told to keep the weight out of the front of the boat and more towards the center/rear


The motor doesnt leak down right away.. Id say 15-30min it will start to settle down. When im at WOT in the boat and trim it up I havent noticed it settling down.

Try different weight arrangements before anything permanent.
I don't think you can have a basic setup for every boat.
If you think about it adding 200 lbs at the stern;it wouldn't be good for hole shot.

 

[edwardz71]

Re: Trim and Prop Questions - 18' Bass Boat

I pretty much have the same set-up as you, 1986 Hydra-Sport 1150 Mercury, I have a 19 pitch 3 Blade and mine runs about 45mph, gets to plane pretty quick and decent hole shot. I don't have but 2 batteries in back though.

Edward

 

[edwardz71]

Re: Trim and Prop Questions - 18' Bass Boat

Dang I didn't realize this thread was started a year and half ago.