New power & a higher bow

[captchuck]

Have had the boat back from repower for about a month and loving every minute of it. just to recap the changes 26' seaway straight inboard. repowered with a 5.7, 300hp, mpi, fwc mercruiser and a 2:1 ZF tran. Spinning an acme nibral 18x17x3 with cup.

Boat runs really nice with the changes and i feel that the prop is tuned properly as she comes out of the hole nicely & 3200 rpms she cruises @ 19 mph (which is about 2mph faster than the old setup) and she is topping out @ 4700 & 32mph which lands in the acceptable specs.

however right from my first run I could tell that she is squatting more than she did. Which isnt the end of the world but i feel i need to have the ability to get the bow down depending on sea conditions and weight distributuon. Right now if I run @ 2500 I am throwing a ferry wake.

This weekend fishing it bacame glaringly obvious to me while running home from fishing. I glassed into the transom an ice box and livewell which were both full and 3 of my crew were leaning sitting up against the transom having a pop what have you and I could barely see over the bow and as is I have a platform for my short ass.

My thoughts are either traditional tabs or lifting rails along the chine (the boat is a hard chine)

Would love to hear some feedback/ other thoughts

 

[El Mar]

No brainer, add trim tabs.

There is no negative effect from adding them, so why not.

 

[traditions]

Try tying a piece of 3/8ths pot warp around the stern.I use sink rope,its easier to get it in place.Tie a bowline in one end and let it sink under the stern and use a scrub broom to push it under there .Tie it up tight and tie the loose end to a cleat so if it comes out you don't lose the rope.Its amazing how much you can drive the bow down.I piece of 5/8ths will put the bow down to the chocks.It give you an idea of how much you need to bring it down.The power trim tabs are nice,but a lot of work boats just glass on a couple wedges on both sides of the stern.Take a 2x 10 and split it edge wise corner to corner making a wedge.About 2 feet long on each side.

 

[Brooksie]

Did you have a cupped prop b/4 ? Cupping can raise the bow. I think tabs are a great idea on a boat this size where variable loads are a higher % of total weight than on larger vessel.

 

[captchuck]

Did you have a cupped prop b/4 ? Cupping can raise the bow. I think tabs are a great idea on a boat this size where variable loads are a higher % of total weight than on larger vessel.

My previous prop was 18x18x3 no cup brass

 

[Brooksie]

My previous prop was 18x18x3 no cup brass

Try it. Since it is almost the same, you could find out if the cup raised your bow...

 

[captchuck]

Try it. Since it is almost the same, you could find out if the cup raised your bow...

My first sea trial was with my old wheel while we were waiting for the new one to come in. With my old wheel I would end up outside the acceptable rpm range for the motor.

 

[JimRP31]

Try tying a piece of 3/8ths pot warp around the stern.I use sink rope,its easier to get it in place.Tie a bowline in one end and let it sink under the stern and use a scrub broom to push it under there .Tie it up tight and tie the loose end to a cleat so if it comes out you don't lose the rope.Its amazing how much you can drive the bow down.I piece of 5/8ths will put the bow down to the chocks.It give you an idea of how much you need to bring it down.The power trim tabs are nice,but a lot of work boats just glass on a couple wedges on both sides of the stern.Take a 2x 10 and split it edge wise corner to corner making a wedge.About 2 feet long on each side.

I have thought about trying this on my SISU 22 but I am afraid of the pressure a rope would put on the lifting rails. Do you have any picture of the Chock set up?

 

[MBILL]

My 2 cents is to add trim tabs and don't look back. You sound like you really need the ability to trim the boat for differing loads and conditions.

 

[finaddict]

Just added the Volvo QL trim tabs to my boat. Can't wait to get that bow down. Previous year added a 60 gallon live well in my transom, so that weight and a few crew members sippin a beverage against the transom made for a horrible ride.

Will let you know how the low profile tabs work. Just wired em up yesterday and launching in a week

 

[Brooksie]

My first sea trial was with my old wheel while we were waiting for the new one to come in. With my old wheel I would end up outside the acceptable rpm range for the motor.

I understand that its not the right prop for your new power, but did the bow lift as much? If not then maybe it is just the cup that is causing it...
Maybe you changed your CG, new power heavier? moved aft? More tankage?

At any rate, install trim tabs, you will love them. It may not cost any more than removing the cup and repitching your prop.

 

[MDI45]

Try tying a piece of 3/8ths pot warp around the stern.I use sink rope,its easier to get it in place.Tie a bowline in one end and let it sink under the stern and use a scrub broom to push it under there .Tie it up tight and tie the loose end to a cleat so if it comes out you don't lose the rope.Its amazing how much you can drive the bow down.I piece of 5/8ths will put the bow down to the chocks.It give you an idea of how much you need to bring it down.The power trim tabs are nice,but a lot of work boats just glass on a couple wedges on both sides of the stern.Take a 2x 10 and split it edge wise corner to corner making a wedge.About 2 feet long on each side.

Iam with Traditions on this one......TRY THE DOWNEAST TRIM TAB....it works!!!....I have done it on J.C's ,H&H's and Wayne Beals and a few other hulls

 

[petrel]

You can always have a couple different size pieces of line for when you need a lot or a little trim. I have seen some pretty small stuff make a significant difference when there wasn't a lot of weight in the back, but we just wanted to roll through some headseas in a skeg boat. It's simple, cheap and can be installed in seconds.

 

[captjohn]

My boat used to run bow high, I had gotten used to it but when I had the props redone by the shop I mentioned it to them. The prop guy recommended going with more diameter, claimed that would add lift to the stern. He actually added metal to the tips of the blades, and they looked perfect when he was done (it wasn't very expensive). Put them back on the boat, ran it, and sure enough, the bow is lower. Might be worth talking to the shop, see if they have a larger prop to try out, can't hurt to try.