Moderated Discussion Areas
  ContinuousWave: Whaler Performance
  Montauk re-power complete /advice on prop selection?

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   Montauk re-power complete /advice on prop selection?
Barnett Childress posted 09-07-2002 09:00 AM ET (US)   Profile for Barnett Childress   Send Email to Barnett Childress  
Have my re-powered Montauk back. Need advice on prop selection. New engine is Yamaha 90.

My normal load/setup; T8 kicker, 24gal fuel, 3 batteries in console, bow mount trolling motor and just me or one other. So fairly heavy. But once in a while I'll have a few others and/or will have to pull some tubes or maybe a skier.

Reccommended WOT is 4500-5500 rpm. Dealer originaly put on a 17" pitch but said boat would max at approx 5-5200 rpm. So he put a 15" pitch on and told me to try that. His reasoning is that I'd be better off with the lower pitch when I run heavier loads.

With the 15" and the same load mentioned above and just me, the engine will over rev slightly @ WOT to about 5700-5800 rpm. At 5500 RPM I'm doing about 42 mph clocked on GPS. Hole shot is also great, boat leaps onto plane.

I know I can just cut back on the throttle to keep WOT rpm's in the proper range but would like to know what others think? Am I under proped or just right?

John O posted 09-07-2002 09:17 AM ET (US)     Profile for John O    
where did you re power.I am looking to do the same and live in Ma. 2 or 4 stroke?
jimh posted 09-07-2002 10:37 AM ET (US)     Profile for jimh  Send Email to jimh     
On my 15-Sport I started with a 16-inch, went to a 15-inch, and ultimately ended up with a 14-inch prop.

I liked the stronger performance of the lower pitched prop, particularly when operating in rough water.

In your situation, I'd rather have a little extra power available for maneuvering when heavily loaded and in rough water. That is in contrast to having a few more MPH available when lightly loaded and in smooth water.

Of course, if you let someone else run the boat, you'd better advise them about the RPM limit.

Also, you could get two props. Change the prop as load and conditions require. You'll also have a spare propeller that way.

Barnett Childress posted 09-07-2002 12:51 PM ET (US)     Profile for Barnett Childress  Send Email to Barnett Childress     
New motors are Yam 2 stroke 90hp and 4S T8 hi-thrust 8hp kicker. I ended up going to Action Marine in Webster. I had a rather large re-power project that included main/kicker motor, dual binacle controls and all new guages. I also had a Merc 904S to trade. They were competive on price and gave me a good trade allowance as they sold both Merc and Yam.

Finally decided to go with them after meeting and speaking to the guy actually doing the work on my boat. He was great and worked very close with me to be sure everything came out the way I wanted.

I do like the performance of the 15 pitch prop and actually will rarely ever run at WOT anyhow. Just doing it now as part of motor break in. I prefer crusing at 3500-4000 RPM any day. I didn't know about the lower pitch being better for rough water!

Bigshot posted 09-09-2002 10:44 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
I ran a 17 and loved it. You may want to try one and see. The dealer will give you a 17. My WOT was right at 5500, even with 3 people it would pull 52-5300. I think the 17 is perfect.
Barnett Childress posted 09-09-2002 09:30 PM ET (US)     Profile for Barnett Childress  Send Email to Barnett Childress     
Thanks Bigshot,
Dealer did say I could try out a 17" prop if I want and keep either one. Yesterday I had the family over for some boating and a cookout. With 2 adults in the boat and pulling 2 good size teenage boys around in tubes (one is bigger than me now :>)I was at 5500 rpm and still not all the way to WOT but had to be very close.
andygere posted 09-11-2002 01:32 AM ET (US)     Profile for andygere  Send Email to andygere     
I get about 5200 with a 17 on my old V4 85 hp. I still get a great holeshot with a heavy load, and 39 mph at WOT. For me it's the ideal prop.
Seabrook posted 09-11-2002 11:09 AM ET (US)     Profile for Seabrook  Send Email to Seabrook     
1983 Montauk with a 1982 115 Johnson. Came with a 17"...too many RPMs. Repitched to a 19"...still too many RPMs. Bought a new OMC 21" with a single cup. Perfect. Sounds like a lot of pitch I know, but it works well on my boat. Top speed did not change from the 19" to the 21", but the RPMs went from 5800 to 5500. WOT is around 43-45, depending on load. Did not go to a higher pitch for top end as I usually only cruise around 30 MPH. I did it so that my cruise RPMs were a little lower.

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.