2004 Rinker Captiva 192...only 42mph on GPS....and overrev

[dgiles]

I just bought a 04 Rinker Captiva 192 with a 5.0 Mercruiser running a 832834A45P23 aluminum prop. Believe that's a 14"x 23P and its hitting 42 mph on the GPS at 5000rpm fully trimmed out. I am a little disappointed with the speed and I think I need to bring the rev's down a little. Any suggestions on what prop to start with? If I get a good suggestion, I might be able to try to test one.

I'm not exactly sure of which sterndrive it is running or gear ratio. Anyway to find out?

Appreciate any help.

 

[Lyle29464]

Re: 2004 Rinker Captiva 192...only 42mph on GPS....and overrev

something is wrong. tach? prop numbers? something. Maybe wrong gears in outdrive.

The numbers say you need a 27 inch prop. The engine with the correct drive should have a 19 or 21.

guess I would check the prop pitch then check tach. You can check you gear ratio by turning over the engine and watching the prop.

 

[Robbabob]

Re: 2004 Rinker Captiva 192...only 42mph on GPS....and overrev

I assume the engine is rated at 5000 RPM max. You are hitting that at WOT and only reaching 42 mph. Confirm the engine is not reving out and protecting itself; meaning, is there any room for more throttle after it reaches 5000 rpm.

Just for fun:
How heavy is your boat?
dry=
loaded passengers and supplies=

Good luck!

 

[jkust]

Re: 2004 Rinker Captiva 192...only 42mph on GPS....and overrev

Yep there is most certainly more going on here. a 5.0 and a 23 pitch prop in that boat would likely get you in the the low 50's under 5000rpms. I'm wondering if you have a tach problem or if your prop has been repitched by a prop shop which isn't uncommon. The sticker on your stern drive will generally denote which ratio it is right on the sticker but there is a standard ratio for the 5.0. If my recollection is clear it is a 1.62:1. Make sure the switch on your tach is in v8 mode and then try a verified prop.

 

[craze1cars]

Re: 2004 Rinker Captiva 192...only 42mph on GPS....and overrev

Here is why people are assuming there is a problem with data provided. They're basing it on prop calculators. Assuming all variables provided thusfar are correct:

5000 rpm
23 pitch prop
42 mph
1.62 ratio

Your prop slip calculates to 37%.

Unless that prop is chewed up to the point that it is missing about 25% of its surface area, that slip figure is completely unrealistic for a 19 ft runabout. Most will calculate between 0% and 15%, depending on cupping, number of blades, etc. NONE will be anywhere close to 37%.

Therefore one (or more) of the above numbers is flat wrong....by a substantial amount.

It's impossible to recommend anything with bad data. Need to figure out which of above numbers is wrong before anyone can recommend a prop.

Post up serial number of the outdrive and someone in the Mercruiser section can probably tell you what ratio it was built with.

 

[dgiles]

Re: 2004 Rinker Captiva 192...only 42mph on GPS....and overrev

Yep there is most certainly more going on here. a 5.0 and a 23 pitch prop in that boat would likely get you in the the low 50's under 5000rpms. I'm wondering if you have a tach problem or if your prop has been repitched by a prop shop which isn't uncommon. The sticker on your stern drive will generally denote which ratio it is right on the sticker but there is a standard ratio for the 5.0. If my recollection is clear it is a 1.62:1. Make sure the switch on your tach is in v8 mode and then try a verified prop.

Agreed that there is definitely an issue. Was planning to run a tachometer to verify the RPM, but I didn't realize that the tach would have V6/V8 switch. But, obviously the boat comes with both engines and it could easily be in the wrong position. The crappy part will be accessing the gauge as this boat has the gauge panel enclosed. Either way, I'll check, thanks.