How to get on plane quicker? 89 Rinker 186 Captiva

newc048

Seaman Apprentice
Joined
Jun 28, 2011
Messages
41
Hey guys, just bought this boat last week and have had it out 3 times now and I've had the same problem each time. Its very tough to get the boat up on plane, I've experienced this with multiple different scenarios, with just me driving, one person up front and one in back and obviously with two people in the back. It helps a bit to have people up front obviously but i still don't feel like it should be this tough.

Ive tried multiple different trim levels and still havent had much luck...

What would you guys suggest? Adding some weight up front, trim tabs, different prop? Im open for any options. This is making tubing, skiing and wakeboarding tough with how slow the boat takes off...

The boat has a I/O 4.3 v6 with i believe a 21 pitch prop according to my buddy. I am a completely new boater and not sure how to check the prop. I know its a stainless steel prop the last owner put on, not the stock aluminum one.

Any help is appreciated!

Thanks so much!
 

boat1010

Senior Chief Petty Officer
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Mar 10, 2009
Messages
781
Re: How to get on plane quicker? 89 Rinker 186 Captiva

To tell if you need a different prop we would need to know what you WOT is. Is your stern drive all the way down when you are starting up? Is there water in the bilge? Check those things out and we ma be able to give you some ideas.
 

newc048

Seaman Apprentice
Joined
Jun 28, 2011
Messages
41
Re: How to get on plane quicker? 89 Rinker 186 Captiva

To tell if you need a different prop we would need to know what you WOT is. Is your stern drive all the way down when you are starting up? Is there water in the bilge? Check those things out and we ma be able to give you some ideas.

When you say WOT, do you mean RPM at WOT? If so then its right around 4500-4800. Stern drive, yes all the way down when starting up. I run the bilge as much as possible and seem to have it dry the majority of the time. Only gets in there when I'm beached or when slowing down the back end will drop in the water and the nose will go up a lot so a little gets in as I need to replace the exhaust hose that connects the lower unit to the hull.
 

TyeeMan

Master Chief Petty Officer
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Feb 27, 2006
Messages
849
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Welcome to iboats! As previously mentioned when you're taking off and getting on plane your outdrive must be all the way down, once your on plane then start trimming up. Also as previously mentioned in order to determine if you need a different prop we/you need to know what your wide open throttle (WOT) rpm is. I think for your boat WOT should about 4600. If you don't have an owners manual open the engine cover and there should be a sticker someplace easily visible with some specs on it like timing, idle rpm, WOT, etc.
If you are at wide open throttle, out drive trimmed up and you're not close to or in the range of the WOT spec, you probably need a different prop.
That said, do you have good fresh fuel, good fuel filter, when was the last time a tune up was done? Is your timing correct? If you have points and condensers when was the last time they were changed? Are your spark plugs, wires, cap rotor in good shape? If any of these items are questionable they need to be replaced, checked or adjusted.
Also make sure your flame arester is nice and clean. I've seen those things so caked full of crap it's a wonder the engin even ran.
 

TyeeMan

Master Chief Petty Officer
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Messages
849
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Looks like we posted about the same time. . .

I hate to say it but if you're getting water in the boat at slower speeds or when beached, you have bigger problems then the exhaust bellows or tube.
I'm not sure of the years or models, but some Mercruisers probably V-6's and V-8's did not have an exhaust bellows. They had a tube, one end was connected to transome sheild where the exhaust exits the boat, the other end that would mate to the out drive was not connected at all. Easy way to tell, a bellows has ribs on it and the exhaust tube is straight, no ribs or ridges and is probably 4-5 inches in length.
I'm betting you have a rip or tear in you drive shaft bellows, , this needs to repaired ASAP!
Something you might want to do is put your boat in the water, tie up to a dock or go someplace out of the way and have somebody else with you to keep an eye out or drive. At idle, not moving,open the engine cover and with the engine running look for water trickling in. Bring a flash light with you. You should be able to see where the drive shaft goes through the transome, look carefully in that area for water trickling in. Look where your shift cable goes through the transome, see if water is coming in there, it should be bone dry back there. Also check any rubber parts (I forget the proper names) of the exhaust system. If the hose clamps are loose they may leak. Your key there is if the water being pumped out is hot or warm, you have a hose leak or one of the rubber deals in the exhaust system.
 

newc048

Seaman Apprentice
Joined
Jun 28, 2011
Messages
41
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Welcome to iboats! As previously mentioned when you're taking off and getting on plane your outdrive must be all the way down, once your on plane then start trimming up. Also as previously mentioned in order to determine if you need a different prop we/you need to know what your wide open throttle (WOT) rpm is. I think for your boat WOT should about 4600. If you don't have an owners manual open the engine cover and there should be a sticker someplace easily visible with some specs on it like timing, idle rpm, WOT, etc.
If you are at wide open throttle, out drive trimmed up and you're not close to or in the range of the WOT spec, you probably need a different prop.
That said, do you have good fresh fuel, good fuel filter, when was the last time a tune up was done? Is your timing correct? If you have points and condensers when was the last time they were changed? Are your spark plugs, wires, cap rotor in good shape? If any of these items are questionable they need to be replaced, checked or adjusted.
Also make sure your flame arester is nice and clean. I've seen those things so caked full of crap it's a wonder the engin even ran.

I do not have an owners manual so I will have to check out in the engine compartment and try to find this stick you speak of. Fuel is fresh as i got it the day of, fuel filter i believe was replaced when the boat was summerized at the beginning of the year. Not sure on the timing and the points and condensers. I will have to check on the plus, wires and cap/rotor. i will also take a peak at the flame arestor tonight. Does anyone know where I can get a manual for this boat, something like a chiltons for the boat? Im fairly mechanically familiar just not familiar with this specific boat and would like to become more capable.
 

newc048

Seaman Apprentice
Joined
Jun 28, 2011
Messages
41
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Looks like we posted about the same time. . .

I hate to say it but if you're getting water in the boat at slower speeds or when beached, you have bigger problems then the exhaust bellows or tube.
I'm not sure of the years or models, but some Mercruisers probably V-6's and V-8's did not have an exhaust bellows. They had a tube, one end was connected to transome sheild where the exhaust exits the boat, the other end that would mate to the out drive was not connected at all. Easy way to tell, a bellows has ribs on it and the exhaust tube is straight, no ribs or ridges and is probably 4-5 inches in length.
I'm betting you have a rip or tear in you drive shaft bellows, , this needs to repaired ASAP!
Something you might want to do is put your boat in the water, tie up to a dock or go someplace out of the way and have somebody else with you to keep an eye out or drive. At idle, not moving,open the engine cover and with the engine running look for water trickling in. Bring a flash light with you. You should be able to see where the drive shaft goes through the transome, look carefully in that area for water trickling in. Look where your shift cable goes through the transome, see if water is coming in there, it should be bone dry back there. Also check any rubber parts (I forget the proper names) of the exhaust system. If the hose clamps are loose they may leak. Your key there is if the water being pumped out is hot or warm, you have a hose leak or one of the rubber deals in the exhaust system.

I believe mine has ribs on it and i know that it is ripped, so i need to try to find the part number to replace this. Think this is what could be causing the majority of the problems?
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Hold on:

1) Exhaust bellows can be totally missing and not cause any water to enter the boat. There is a larger, and ribbed, bellows directly above the exhaust bellows, this is the one (U-joint bellows) that can cause water intrusion and you need it right.

2) If you are taking water over the transom when you come off plane, then just give here a little bit of throttle right as she settles and that will solve that. You'll get it as soon as you try it.

3) If she is pulling a 21 inch prop to above 4500 RPM then I believe the performance is good. You need to verify the tach is accurate and I'd like to know the top speed you're seeing, very preferably by GPS. This will help us verify your performance numbers as they are.

Oh, oh, welcome aboard! If all of this checks out, then there are some other things that can be done to improve hole shot. How does she ride at top speed? Does she "porpoise" at all? That would be a sort of bouncing of the bow over and over. If so then you could shift some weight forward, but we never want to add weight, just maybe move what we have around some. We will also be wondering about soaked floatation foam under the deck (floor). That could be the entire issue.

And after we confirm all is right, then ultimately, trim tabs are the best solution for maintaining top speed and improving time to plane and bow rise. Once she's right, I'd go there no matter how good she ends up . . . ;)
 

TyeeMan

Master Chief Petty Officer
Joined
Feb 27, 2006
Messages
849
Re: How to get on plane quicker? 89 Rinker 186 Captiva

You probably won't find a manual for your specific Rinker BUT, if you get out of this section of the forum, scroll down to the engine repair part, scroll further down to Mercruiser I/O, inboard engine section, at the top you will find in the "stickies" a whole host of Mercruiser manuals that you can down load, thanks to Don S. I think you will need your engine and drive model numbers to down load the correct manual. These are the official Mercruiser manuals that will have all the info you need. Don't waste your money on a Chilton or Clymers manual.
 

newc048

Seaman Apprentice
Joined
Jun 28, 2011
Messages
41
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Hold on:

1) Exhaust bellows can be totally missing and not cause any water to enter the boat. There is a larger, and ribbed, bellows directly above the exhaust bellows, this is the one (U-joint bellows) that can cause water intrusion and you need it right.

2) If you are taking water over the transom when you come off plane, then just give here a little bit of throttle right as she settles and that will solve that. You'll get it as soon as you try it.

3) If she is pulling a 21 inch prop to above 4500 RPM then I believe the performance is good. You need to verify the tach is accurate and I'd like to know the top speed you're seeing, very preferably by GPS. This will help us verify your performance numbers as they are.

Oh, oh, welcome aboard! If all of this checks out, then there are some other things that can be done to improve hole shot. How does she ride at top speed? Does she "porpoise" at all? That would be a sort of bouncing of the bow over and over. If so then you could shift some weight forward, but we never want to add weight, just maybe move what we have around some. We will also be wondering about soaked floatation foam under the deck (floor). That could be the entire issue.

And after we confirm all is right, then ultimately, trim tabs are the best solution for maintaining top speed and improving time to plane and bow rise. Once she's right, I'd go there no matter how good she ends up . . . ;)

1) I will take a picture of what is ripped tonight to better explain. I'm a complete rookie at all of this so that will be the best way to show you guys.

2) I attempted to do that a bit yesterday and will keep working on that to see how much that helps.

3) I GPS'd it yesterday with just me in the boat on somewhat choppy water was 44mph top speed. I have a feeling on calmer water i could definitely go 46-48. Im happy with the top speed just would like to get up to that quicker and not ride a wheelie for 1-2 minutes before getting up on plane :p What would be the best way to test the tach? up and down the RPMs it seems close so i don't see it being off much if at all, but always willing to test to confirm.

Once it gets up on plane I'm very happy with how she rides. I'm sure some weight relocation couldn't hurt but overall I'm happy with the cruising speed and condition.
 

newc048

Seaman Apprentice
Joined
Jun 28, 2011
Messages
41
Re: How to get on plane quicker? 89 Rinker 186 Captiva

You probably won't find a manual for your specific Rinker BUT, if you get out of this section of the forum, scroll down to the engine repair part, scroll further down to Mercruiser I/O, inboard engine section, at the top you will find in the "stickies" a whole host of Mercruiser manuals that you can down load, thanks to Don S. I think you will need your engine and drive model numbers to down load the correct manual. These are the official Mercruiser manuals that will have all the info you need. Don't waste your money on a Chilton or Clymers manual.

Thank you TyeeMan! I will do some research and get a manual downloaded asap!
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How to get on plane quicker? 89 Rinker 186 Captiva

3) I GPS'd it yesterday with just me in the boat on somewhat choppy water was 44mph top speed.
BTW, choppy can sometimes be slightly faster . . . Can you verify the RPM you saw at 44? Tach looks right from my first glance. I am using a 1.84 gear ratio for that and assuming that the 21 pitch is right. How many blades?
 

newc048

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Joined
Jun 28, 2011
Messages
41
Re: How to get on plane quicker? 89 Rinker 186 Captiva

BTW, choppy can sometimes be slightly faster . . . Can you verify the RPM you saw at 44? Tach looks right from my first glance. I am using a 1.84 gear ratio for that and assuming that the 21 pitch is right. How many blades?

I would say the rpm was right around 4400-4500, 3 blade prop.
 

TyeeMan

Master Chief Petty Officer
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Feb 27, 2006
Messages
849
Re: How to get on plane quicker? 89 Rinker 186 Captiva

When your running 46-48 mph what is your rpm? With just you in the boat + gas, anchor etc you should be able to come up to max WOT, in your case 4800 and have to throttle back just a touch or you'll over rev, , , if you have the correct prop.
If you can only achieve say 4500 at WOT with just you in the boat then I would say you could easily drop at least 1 pitch size or 2. So if you currently have a 21" pitch you would drop to a 19" pitch or even a 17. Typically they go in 2 inch incraments. When you drop in pitch you typically go up in diameter of the prop.
Just in case you didn't know, when we say 21 inch pitch or 19 inch pitch, that means theoretically with every rotation of the propellar the boat will travel 19, 21, etc inches forward. In reality that doesn't happen as water has slip to it, but it's kinda close.
 

QC

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Mar 22, 2005
Messages
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Re: How to get on plane quicker? 89 Rinker 186 Captiva

I agree with everything ^^^^^ except:

When you drop in pitch you typically go up in diameter of the prop.
Diameter probably shouldn't change. A 19 may be the answer and then keep the 21 as your spare (you need one). Especially important that you go to the higher end of the WOT range when very lightly loaded, that will make the prop right with moderate to heavier loads.

I'm going to leave this thread here as an example of narrowing down the issue in the Boat Section and then we can nail it down in the appropriate section, i.e. Props. I think your top speed indicates decent engine performance pulling a 21 like that, so this seems like a get it right thing, not that there is an engine or prop problem. In fact that prop may be perfect with very little load, but she will be sluggish out of the hole as you have found.

One more thing, repeated, say it very slowly and then start searchin', T R I M T A B S . . . ;)
 

superbenk

Commander
Joined
Oct 27, 2008
Messages
2,022
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Yep, Smart Tabs is a simple & inexpensive fix. From what I read, rpms & speed all sound ok to me.
 

dockwrecker

Lieutenant
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Mar 10, 2006
Messages
1,392
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Fix the bellows and while you're at it the shift cable boot. Quit putting everything in the back, move crap forward. Smart tab it and be happy. The prop sounds fine.
 

superbenk

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2,022
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Do you guys think these smart tabs will do the job? http://www.nauticusinc.com/smart_tabs.htm Haven't decided between the regular metal Smart Tabs, or to get the plastic Smart Tabs SX's, what would you guys suggest?

I've been using them for the past couple years (plastic) just fine. They made a world of difference in the way my skinny old boat performs, tracks & generally handles. iBoats used to have factory blemished tabs at a discount. That's what I got & they were $20ish cheaper than perfect ones & I still haven't found what the blemish is - they look & work perfect as far as I can tell. Not sure if the blemish deal is still around.
 

newc048

Seaman Apprentice
Joined
Jun 28, 2011
Messages
41
Re: How to get on plane quicker? 89 Rinker 186 Captiva

Here is a picture of the ripped bellow, definitely the Exhaust bellow-
2011-08-16221246.jpg


Is it fine to run like this for a couple more months this year then replace during the winter? Could this be what is causing water in the bilge? The u-joint and shift cable bellows looked perfect and no rips/tears/leaks.
 
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