New owner of a 2001 rinker 180!

mathiasg

Hello everyone, I am new to this forum and have done many searches to find the answer to my question but I'm having no luck so here it goes.  It's a 2001 rinker 180 open bow with the 3.0 merc.  The boat has very low hours, less than 20.  I have gone through the boat and gave it a full tuneup.  Here's the problem I'm having.  At wot I'm running at 4200 rpm and I should be between 4400-4800.  Its running at 41 mph on the speedo with 4 people on the boat and very light gear.  I know the speedos aren't correct but I don't have a portable gps yet.  My problem is getting on plane,  it's so slow out of the hole.  I tryed pulling my 200lb brother on a single ski and we stopped after two attempts because I didn't have the holeshot, it was just dragging him a slow speed,  I know the engine is strong with no problems (compression is within specs on all cylinders).  I have smart tabs on the way because I hear lots of good things on them but I can see mounting them is going to be a problem.  So is this normal for this boat or am I over propped?  My prop is a 3 blade aluminum 15x19p and has anyone ever put smart tabs on this boat.  Anything you guys have to say is greatly appreciated.  Thanks

Black_Diamond

Sounds like you are over propped.  You need to drop about 3" of pitch to move up where you need to go on RPM.  1" of pitch change is equal to about 200 rpm (less pitch = higher RPM and vice-versa).  Then you get into the wizardry of prop types...it's almost test drive to see what works for you.  There are several threads on here about prop sizing worth reading.

KYSEAN

I would highly recommend a 17P Mercury Spitfire 4 blade prop. It will get you in a good rpm range and your boat will plane fast. It's an aluminum prop with an affordable price tag. Can't go wrong with it.

mathiasg

Thank you for your help, I will look into that prop.  So stay with the 15 and change the pitch to  17?  15x17p spitfire 4 blade prop

midweste

Hi Mathias! 

Welcome to the RBOC, and congrats on your new boat! 

I have the same boat as you do and love it. 2000 180 bow rider with a Merc 3.0, Alpha One Gen 2 drive, 2.00 gear ratio.  I have a 14.5 x 19 Mercury quicksilver aluminum prop and have no problem getting on plane, pulling a tube or someone on water-skis. The prop size was recommended by Randy Rinker and at WOT my RPM is 4200. I don't have the top end you do (37mph clocked on Precision Star GPS speedo), but I like the current setup and it works well for me. Your RPM at WOT sounds a bit high for the Merc 3.0 motor. Sounds like you aren't propped correctly. I would try the OEM recommended prop size, 14.5x19.  

Getting on plane takes a bit if you have passengers and gear aboard, but I do it every time I go out. As long as you have the outdrive trim all the way down, give it full throttle, then have a few of the larger passengers sit in the front, you should get on plane with no issues. After you are on plane, you can ease the trim back a little and really dial it in. 

Fourth of July weekend:  I had seven adults, a 9 year old, two full coolers, fishing gear, tubes, etc.. and was able to get on plane and top out around 34mph at 4200RPM WOT. Our hulls are rated for 8 people. 

There are really good free GPS Speedo apps for smartphones available. I used a few of them before I upgraded to the Precision Star GPS Speedo. 

As my forum colleagues can attest: It is not uncommon for even the largest Rinker EC boats to shift passenger loads to the bow to get on plane quicker. 

mathiasg

Thank you midweste, that's good to know you have the same boat and that prop works good.  I forgot to mention the ratio of my alpha one gen2 drive is 1.81.  Do you think it would help at all to get your prop size but go stainless or just stick with the aluminum?  Thanks again!

midweste

No Problem! I chose the aluminum prop for now since the lake I frequent most has some sandbars. I found it new on Eb@y for $100 shipped! I am looking for a SS version around the same size as OEM right now, but haven't settled on one just yet. 

You'll be very happy with the OEM 14.5x19 Merc QuickSilver prop.

I'll let you know when I get a SS prop and how it behaves.. 

 

Black_Diamond

I would think the prop pitch should change from a 1.81 to a 2.0 ratio, that cuts the torque by 10% at the prop and the prop rpm by the same ratio.  You need less pitch, probably 1-2" (200-400 rpm increase) less that whatever you are running.

midweste

Mercury Quicksilver Black Diamond Propeller QA1916X 14 1/2 x 19 RH

midweste

+1 BD, I would check around to see what prop is OEM spec'd for that ratio drive for sure.. 

mathiasg

You Guys make a good point with the different ratio and going down in pitch to get out of the hole better and running in my wide open throttle range.  I'll keep researching and let you know the outcome.  Thanks again.

raybo3

Welcome to the RBOC and good luck with your new float. Lots of great info here.

lmaylen

I have a 2003 180 rinker. 3.0 mercrusier Alfa 1.  Was running 14x19  3 blade almum. Prop weak hole shot 4800 wot. 38 mph. Loaded was not good tried couple diff prop best ss 14x17 4 blade 4800 wot 38 mph lot better hole shot plus more power  loaded and this was recommended by a good prop shop for my boat very happy with this prop

midweste

Four blade SS sounds interesting... What brand is it? 

What gear ratio is your Alpha One?