Performance expectations for FV 250 with Merc 5.0 MPI and bravo 3

jason

Hello all,

This is our first year with our boat.  I would like to understand what are reasonable expectations for performance from our boat.  Normal crew is me, my wife and our 7 year old son.  I am curious to know, how long should it take to get on Plane, and what should our top speed be.  Also, how would this differ if we had 4 adults and 4 kids?

Any insight or personal experiences would be greatly appreciated.

Regards from Lake Simcoe, Ontario,

amajamar

I have a 2004 FV 250 with the same setup.  I was having some planing issues with four adults and two kids a couple of weeks ago. (see my earlier post in this forum)  With every one aft, the boat was really having a tough time staying on plane once up, it seemed like the swim platform was catching the water and pulling the boat back until it fell off plane.  It was better when I moved the kids below and my largest passengers slightly forward,but there were two to three foot seas and I wasn't too impressed by the boat's performance.

Last weekend just my wife and I were out in calmer water and the boat got right up and planed nicely at 3400 rpm and 25 MPH or so.  I felt better then, and since I'm new to the boat, I know that there is a learning curve that will take a bit to master.  Frankly, I would opt for more engine in my next boat, but other than that and a few minor nitpicks, I am happy with it.

TikiHut2

Jason, welcome to the forum. As for our '04 270 w 5.7 300hp merc and B3, it takes some finesse to get our RV of a boat on plane quickly and a bit more if i have more than 3 souls on-board. Do a search in the archives and you'll find other discussions but basically: 

Assuming calm seas and 3crew, from idle, tabs full down, and OD trimmed fully down. Ease on the throttle for a couple seconds to gain some momentum and then roll it on to about 90% throttle. As my boat reaches about 20mph I pull the tabs fully up and the boat gains speed quickly. At that point I set the rpm to about 3800 and raise the OD just until the boat starts to begin to porpoise then trim it back down slightly until it settles. All this should only take about 6-10secs

At this point I'm at about 3800rpm and 27mph+/-  using fuel at about 1.8gph at optimum trim.

As mentioned, some '03 and older Rinkers had the swim platform mounted low enough that they hindered performance. Luckily that was changed on our 270's model year and newer. Keeping weight like coolers/crew/gear off the stern will greatly help in planning time. Stow everything amidship and/or forward.

Hope that's what you were looking for. Have a great season. Mike

Babyboomer

amajamar

TikiHut2 said:

Jason, welcome to the forum. As for our '04 270 w 5.7 300hp merc and B3, it takes some finesse to get our RV of a boat on plane quickly and a bit more if i have more than 3 souls on-board. Do a search in the archives and you'll find other discussions but basically: 

Assuming calm seas and 3crew, from idle, tabs full down, and OD trimmed fully down. Ease on the throttle for a couple seconds to gain some momentum and then roll it on to about 90% throttle. As my boat reaches about 20mph I pull the tabs fully up and the boat gains speed quickly. At that point I set the rpm to about 3800 and raise the OD just until the boat starts to begin to porpoise then trim it back down slightly until it settles. All this should only take about 6-10secs

At this point I'm at about 3800rpm and 27mph+/-  using fuel at about 1.8gph at optimum trim.

As mentioned, some '03 and older Rinkers had the swim platform mounted low enough that they hindered performance. Luckily that was changed on our 270's model year and newer. Keeping weight like coolers/crew/gear off the stern will greatly help in planning time. Stow everything amidship and/or forward.

Hope that's what you were looking for. Have a great season. Mike

Mike,

That's quite a procedure, but I'll give it a try myself!  Can you explain a couple of things for me though?  What does lowering the tabs first then raising them to pick up speed do?  Also, could you explain how to trim the outdrive to help with planing?  I would think that anything other than fully down would tend to lift the bow which seems counter-intuitive to me. Sorry for all the questions, but I too am new to boating and would like to learn how to efficiently trim the boat to plane.

Thanks!

TikiHut2

Assuming your boat has them, Trim tabs are both used in a downward angle(usually about 45*) to help lift the boats stern up on plane, or used independently to trim poorly adjusted weight in the boat. When both are trimmed downward they are quite efficient up to a certain speed(18mph +/- for us) at which point they become more drag than lift. Moving them into their upward position paralell to the hull eliminates that drag when the boat no longer needs their help as it's running at speed on the hulls surface in full plane.

Combined with the stern drive/OD trimmed fully down at the beginning of your run up to planning speed the OD is also slightly lifting the stern while pushing the bow downward on to planning position. This isn't an angle that is efficient or safe at planning speed as it's driving the bow down creating dangerous over steer. Trimming the OD slightly up raises the bow at speed creating a better ride and allowing the hull to balance more efficiently on the relatively flat sections of the hull. Trimmed up too much and the boat may bounce/porpoise seeking it's balance point which indicates you have the OD too far up.

Hydro dynamics aside just imagine your hand out the car window trying to create lift at slow speed just like a trim tab. A higher angle lifts your hand at slow speed but become unstable at high speeds, Trim tabs create work in a similar way. In addition when your hand is trimmed flat/balanced at speed there is little resistance and fuel efficiency/speed is improved. In another analogy the boat hull itself seeks balance like a surfer on a board. Too far forward or back on it's balance point and it's a mess. With weight and trim balanced it's nirvana and all the Polynesian girls are impressed.

Getting out of the hole and onto plane quickly/efficiently is the 1st goal. Re-trimming for fuel and steering efficiency is the very important 2nd phase once you're planning. Trimming for load mismanagement and sea conditions is another lesson that will come with time.

That may not make any sense but I hope it helped. Have fun and be safe. Mike

jason

Thank you all for the responses. 

Mike, I really appreciate the detail.  My 250 is currently taking at least 30 second or more to get up on plane.  I will stop watch it this weekend.  I seem to hit about 3000 rpm quickly and then gets stuck there for a long while, just inching up so very slowly.  I am using the trim tabs as you mentioned but I will pay closer attention to when I raise them.  Once on plane things are good.  She cruises at 24 to 26 mph nicely and will do 31 at WOT.

Based on your comments, I think I should expect better.  I will start with a tune up and go from there.  I will post the results as I go.

amajamar,  I can't agree more.  If I were to buy again I would go with more power, but we are so happy with the boat in general, that I wouldn't want to let her go.

Thanks all,
Jason

TikiHut2

Do you have the boat packed with heavy gear in the stern? Ditch the junk and move other heavy stuff forward. I rarely carry more than a half tank of fuel or water. It adds hundreds of pounds in the stern. Im slways amazed at how lively the boat is when its just me alone.

What year is it? Maybe its a swim platform issue.

Clean fuel and filters is an important start. They're thirsty and want plenty of high octane to get going.

Good luck and let us know how it goes. Pics are good too. Be safe and have fun. Mike

browncbr1

hey tikihut, 

what pitch prop are you using.. I have the same boat, power, drive, but 2005 model with 22 pitch props and really having to run her **** high rpms to keep up on plane...  wondering if you have the 24 pitch props?  thanks craig

TikiHut2

I typically cruise (assuming neutral weather/water conditions) at 3800rpm doing  27mph, tabs up and OD trimmed slightly back from horizontal using 1.8gph at best trim. Don't get me wrong about being minmalists re on-board gear and weight. We are packed for bear when we are out for a weekend and the boat still performs fine for what it is. It's about trim out of the hole and keeping weight out of the stern.

Here's what I have for props....Yeah they could be polished but happy hour always seems to fall right when I get to that point on the to-do list or my boat budget is shot. Hey, Good luck. Hope that helps. Mike

browncbr1

yep, we have the same props... I hit mine with some sand paper to get the scaling off... should be smooth today, and I just installed my new tach,,.. so i'll get some more accurate readings and see where i'm at.. thanks!

Craig

Maverick

Jason, my set up is the same as yours but with Alpha 1 gen 2. 30 seconds to plane seems too long. Great Hydrodynamics lesson from Tikihut 100%! The swim platform thing shouldn't be a problem with the 250, it's an older 270 problem. Weight and weight balance is the key, 1/2 fuel 1/2 water and weight further forward. Is your hull/drive clean? Tabs down and leg right down to start! I had 8 full size adults out last month (admittedly 2 sitting on the bow) but 3 on the back seat and we still planned in under 30 seconds! Interestingly my WOT is 4800 rpm and 31-34.

212rowboat

Four things on an engine can make that happen without a noticeable event leading up to it.. which, in short, is an engine reaching full throttle but after long bog.. this is just speaking of the engine, though, and not load or drag limitations..

Air in: bad induction due to obstruction... Check filter..

Air while in engine leaking out, such as vacuum leak.. easiest way to find one is a can of ether or starting fluid in aerosol can lightly sprayed around intake manifold while engine is running, but carefully avoiding air box.. for the love of God, turn the blower on, though!! :-)

Obstructed fuel vent.. you gotta have an open loop for the pump not to fight the vacuum it creates... A dying fuel pump will do this, too. Mpi is an electric pump, right?

Obstructed exhaust.. an engine may fight to expel at lower rpms, but achieve enough pressure once a suitable rpm is reached to negotiate the obstruction, as in, push it out of the way.. this is really common on engines with a catalytic converter, right before they clog up tighter than a drum.. I don't know if the newer marine engines have emissions, but if they do- first thing I'd look for.. running rich with cats for a while will do this.

browncbr1

Well, I went out on Sunday. 1/4 water tank. 1/2 fuel tank. And two of us until the in laws unexpectedly showed up uninvited and insistant to go out with us. Unfortunately, they are about 350lbs each. They also preferred the back seat at all times. Wind was 10-15, Bimini top up, tabs up, and cruise @ 3800rpm was 25-28. Water was not smooth. Maybe next weekend will have a clearer picture.

I also forgot to check the spark arrester.

tundra250

I have an 02 250 with 5.0 dual prop and 2 people in the boat 40 - 42 mph WOT......I've had  6 in the boat and got 38 mph.....Lake George NY.....some chop

amajamar

TikiHut2 said:

Assuming your boat has them, Trim tabs are both used in a downward angle(usually about 45*) to help lift the boats stern up on plane, or used independently to trim poorly adjusted weight in the boat. When both are trimmed downward they are quite efficient up to a certain speed(18mph +/- for us) at which point they become more drag than lift. Moving them into their upward position paralell to the hull eliminates that drag when the boat no longer needs their help as it's running at speed on the hulls surface in full plane.

Combined with the stern drive/OD trimmed fully down at the beginning of your run up to planning speed the OD is also slightly lifting the stern while pushing the bow downward on to planning position. This isn't an angle that is efficient or safe at planning speed as it's driving the bow down creating dangerous over steer. Trimming the OD slightly up raises the bow at speed creating a better ride and allowing the hull to balance more efficiently on the relatively flat sections of the hull. Trimmed up too much and the boat may bounce/porpoise seeking it's balance point which indicates you have the OD too far up.

Hydro dynamics aside just imagine your hand out the car window trying to create lift at slow speed just like a trim tab. A higher angle lifts your hand at slow speed but become unstable at high speeds, Trim tabs create work in a similar way. In addition when your hand is trimmed flat/balanced at speed there is little resistance and fuel efficiency/speed is improved. In another analogy the boat hull itself seeks balance like a surfer on a board. Too far forward or back on it's balance point and it's a mess. With weight and trim balanced it's nirvana and all the Polynesian girls are impressed.

Getting out of the hole and onto plane quickly/efficiently is the 1st goal. Re-trimming for fuel and steering efficiency is the very important 2nd phase once you're planning. Trimming for load mismanagement and sea conditions is another lesson that will come with time.

That may not make any sense but I hope it helped. Have fun and be safe. Mike

Fantastic Mike!  Thanks for the explanation!  I was out this weekend with four adults, low water 3/4 fuel and it seemed to plane much better.  I find that 1/2 tab down was the quickest to get on plane, but I think that I was leaving the tabs on that setting while cruising...  I'll have to remember to raise them up again after getting up and see how it handles.  That, and trying trimming the OD up a little at the same time... another thing I need to play around with.  It was a short trip out due to slightly rough water and in-laws on board...

TikiHut2

Glad it helped!! Yeah, trimming to get on plane is only half of the job, re-trimming for cruising speed is the 2nd half where the boat performance excels.

Have a great season. Mike

shdwridr

I may be late on this issue, but I joined this forum today about my fueling problem,

came across this discussion a little late, but have a mechanic coming out

Tuesday to find out why I can't get my 2003 fv250 with merc 5.0 mpi brovo 3

on plane. I even put 150 lbs of sand in my bow, still didn't help. I will let everybody

know if the mechanic finds any magical potion or anything like that

jason

Hello all,

I can't believe the seasons over and I have been totally delinquent in posting.  I just wanted to follow up to let you know what the source of my problem was and that the boat now gets up on plane in aprox. 10 sec. with a couple of adults on board.  BTW, the trimming advice from Mike is so much more fun to follow now.  Actually got a little feaked out the first time out after the fix because I was used to having so much time to raise the trim tabs and ease off the throttle.  So what was the problem you ask. 

Rotor!  See Picture below.  Notice where the center contact point 'should be'

My dad (retired mechanic) and I did a tune up the July long weekend.  When I pulled the rotor and showed him he said that he couldn't explain why the motor would even start.

Regards all,
Jason

Black_Diamond

You can clean those props up real easy, douse them with "The Works" toilet bowl cleaner (not the thick stuff) and rinse.  You'll be amazed.  Watch the concrete though..it will etch it.

TikiHut2

Great to hear about a solution that's outside the box. Somebody will check theirs because you posted. Have a good winter and start counting the days until its back in. Cya mike

Dream_Inn

Thanks for posting back.  As Tiki said, someone will learn from it.

Michael T

Re: prop crud cleaning. I was told by an old salt to tilt my drives down when using CLR, muriatic acid or the works type products as it was his opinion that they were semi-caustic and would damage the seals in the drives. He advised using a paint brush (not a spray bottle) putting a pan under the props and painting on the liquid in question repeatedly until the props were clean. He said just keep dipping your brush in the drip pan so you don't waste the cleaner. Sounded reasonable to me and I cleaned my b3s that way pretty fast - then just a wash the props with the garden hose NOT a high pressure washer. I cringe when I see some kid at a marina using a dialed-up pressure washer on drives! MT

Black_Diamond

@MT: The seals really should be ok, but not a bad idea, especially brushing it on otherwise you do waste a lot.  We end up using pressure washers around here though: zebra and quagga mussels hide in every crack and crevise and it takes a lot to remove them as they sick on like crazy glue.  Thank you Russia for that donation.

Piper

Hi, new to the forum (and to Rinker).  Have an '04 250 that can't get above 3600 rpm and about 25mph.  Had everything checked and replaced --- tstat, sea water pump, plugs, elbows cleaned out etc.  It's a bravo 3 5.7.  Also overheating after about 15 minutes running.

Now I'm being told the hull is a bad design and needs more power to move it.  Also looking at different props.The boat has been in the shop all summer and I'm at the end of my rope.  Any comments/suggestions?  I guess I need confirmation that Rinker is not a bad boat.

Black_Diamond

Welcome aboard!  A bad (corroded) circualtion pump can do that (the 'water pump' like on your car).  There is no way you are underpowered IMO.  More will chime in here!

TikiHut2

Piper, My '04 270 has the same engine/drive setup and is considerably heavier with no lack of power so it's something else. Maybe it's a defective mechanic..... just sayin'. Could be time to get to the root of the problem with someone else. Engine codes are all good and fuel supply is too?

Feel free to start a new thread that would help keep your issue from getting diluted by other owners slightly different problems too.

Welcome to the forum. Someone here will hopefully have your answer. BD had a pretty good idea there. Engine temps have to be right before props become an issue IMHO. Good luck, Mike

212rowboat

It could be grossly overloaded due to props with too much bite.. which would cause overheating.. or, bottom barnacled up..

comm1

my brother had an older boat with a 3.8 liter and had essentially the same problem and after a couple of grand $$, changing almost everything including redoing the heads, the culprit was a bad distributor and it was overlooked cause the previous owner had changed it before selling the boat, it will be a process of elimination!

Piper

Appreciate all the suggestions.  Bottom is clean, about 1/4 fuel, rotor replaced, think the "engine" pump was checked too.  Engine doesn't sound or run rough but going to try shorting out each plug to confirm all cylinders are firing.

The comment by the Mercruiser dealer about Rinker being a "bad design/bad boat" really rattled me.  From all I've read I thought they were decent boats.

Again, any comments gratefully received

Cheers

Black_Diamond

It is pretty hard to just 'check' the circulation pump, just saying, I bet hardly anyone looks for eroded impellors on them but it happens. You could pull the thermostat and run without it, the engine will run cold if all is well, if it overheats then you have more to look at.  Have they tried running the motor while on the hard with muffs?

 

I think you'll find a whole crew here who will dispute the 'bad design/bad boat' comment.