More power

B

Bammy674

New Member
Jun 26, 2009
3
Falconer, NY
Hey all, Ive got a 26' '84 weekender. It seems like it has the power but just doesnt wanna go like it should. It only has a 260 hp Merc but something just doesnt seem right. Also it just doesnt seem to wanna plane out either. Am I doing something wrong? Would a different prop help with the power? Id appreciate any suggestions
 
Please give us more detail.

When you say you have a 260 hp Merc I assume you have a 5.0L V8 with carbs, right? What drive?

When you are wide open throttle, what are the RPM’s? What is the speed of the boat?

Do you have power trim and after you get on plane do you trim the boat, meaning you raise the trim until that bow rumbling sensation is minimized.

What type and pitch of prop do you have? How is its condition? How is your hole shoot? From a dead stop how long does it take you to get on plane?

Do you keep the boat in the water like in a slip? Is the bottom clean our fouled?

Engine maintenance questions: When was the last time you changed ignition components like spark plugs, plug wires, rotor and cap?
 
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One summer after launching my nemesis, a 26 footer with a 350 cid 260 hp Alpha One it would plane and run badly. A few weeks later with a boat load of guests, she wouldn't plane at all turning 3200 @ WOT, until the hub spun. Limped back to the dock and ran to drove over to a dealer to get a new prop. Replaced the prop and the boat ran normally.

Apparently the "exact replacment" but less expensive Michigan prop I got at Boat/US was crap and the only thing that worked right was a Merc prop. Try a different prop that's the right size first. Then begin looking for problems.

Best regards,
Frank
 
That 260 hp should be a 350 with a four barrel carb.

A 268 is a lot of boat for that engine. Take Frank's advice and check the prop.

Also, is the bottom clean? What is the WOT RPM and speed?
 
Ok, here is what I know so far. It is a 5.0 V8, not sure what drive. At full throttal I am running about 4500 RPM's. I do have power trim but I think I had them backwards in my head, which was prolly most of my problem. It should be bow up at start them bow down as you get up to speed right? I believe it has a 15x15 prop but have not verified that for myself yet and looks like it has a few dings in it but not in terrible condition. It is kept in the water and was already in the water when i bought it, so im not positive of the condition of the bottom. Unsure when the last maitnance was done on the motor but can find out. The previous owner did keep up on everything and took very good care of the boat so i would assume he had regular maitnance done prior to launching this season. I dont have a speedometer but my max speed seems to be about 25mph. Is that normal or is there anything else I should do or change. Thank you all for your replies.
 
A 5.0 in a 26' Sea Ray? OUCH! Say it isnt so.
With a 5.7 There's a 40% chance you would still feel underpowered.
 
Bammy674,

If you have the 5.0 V8, then you're rated at 228 hp. way underpowered (I have the same engine in my 225CC and that is underpowered). if you have 260hp (as your first post indicates) then you have the 5.7 V8, and should at least be adequite. Both engines were most likely mated to an alpha one drive (if you have mercruiser).

As frank said, try new prop, maybe even a 4blade to get the hole shot you're looking for (or you can try a fin).

Good luck!
 
Bammy674 said:
Ok, here is what I know so far. It is a 5.0 V8, not sure what drive. At full throttal I am running about 4500 RPM's. I do have power trim but I think I had them backwards in my head, which was prolly most of my problem. It should be bow up at start them bow down as you get up to speed right? I believe it has a 15x15 prop but have not verified that for myself yet and looks like it has a few dings in it but not in terrible condition. It is kept in the water and was already in the water when i bought it, so im not positive of the condition of the bottom. Unsure when the last maitnance was done on the motor but can find out. The previous owner did keep up on everything and took very good care of the boat so i would assume he had regular maitnance done prior to launching this season. I dont have a speedometer but my max speed seems to be about 25mph. Is that normal or is there anything else I should do or change. Thank you all for your replies.
Click to expand...

You have it backwards allright. Try this...put the drive all the way in the water and see what you get:thumbsup:

Witha 260 in a boat of that size you need to leave the drive down and work your trim with the trim tabs...they should be all the way in also. After you get the feel for it, you might pick up a MPH or so with a light load but don't count on it. If you have a 5.0 litre Small Block Chevy in that boat the engine has been replaced and it is grossly under powered. Sea Ray never offered that package for that reason. Get a cheap hand held GPS and check your speed. If you are getting 25 MPH at 4500 RPM with a 15" prop you are doing ok. You have a very heavy boat and without Big Block torque and a Bravo drive you are at your limit with a Small Block Chevy.

Make a note from Tail Chaser's signiture...he's replacing a 260/Alpha with a 8.1 Mag/Bravo 3. That will be a sweet package.:thumbsup:
 
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I agree the size boat sounds like the 350 is a little sluggish as I have experienced similar in my 23 weekender fully loaded in 20knt seas. Im currently rebuilding 454 bravo which i should fit over next couple of weeks, Little concerned with fiiting inside hatch with slight mods in shifting fuel tank further forward to maximise space
 
keokie fit both 454 and 502 in classic 26' Sea Rays
The serpentine belt on the 8.1. Makes the engine a little longer? Looks like the 8.1 will hit my tank by 1/4". Trimming the tank 4" will drop my capacity to 80 gals like the new 26'ers. I'm adding a 40 gal belly tank for ballast and more capacity.
Extending your main tank down 6" in the center to the V bottom is good for 10 gals. If your fresh water. you could get more capacity going snug to the bottom. Wouldn't want salty bilge water on the tank.

I couldn't believe Sea Ray did not glass both sides of the stringer at the motor mounts. Inside and edge only toward engine, not even sealed on the bottom:huh:
Get the saw out. Make sure the rest of the ER is not the same. Glad I'm not doing all this work for another 5.7
Think I will add more stringers also. Build it like a 50 mph boat :grin:
 
Hi Guys,
Which would be the best suited prop for my application in my weekender 23 with the Bravo 454 The searay web site says 17 mirage. Lots of props have come out since.
Any recomendations
 
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