Minnesota Classic Glastron Forum

General Category => General Discussion => Topic started by: not2worried on July 05, 2010, 05:11:45 PM

Title: High Rpm, no acceleration when pulling tubers
Post by: not2worried on July 05, 2010, 05:11:45 PM

Went out this weekend. Boat ran good. But while trying pull the kids on a tube, the boat would begin to pull, start to incline. I began giving more throttle to level it out. The Rpms climbed, but was not going any fast.
Is this a prop issue? Air in the water?  The area in which this happened was somewhat weedy. I have pulled people on a tube before much heavier then my young kids. Didn't really experiment to much. It happen a 2-3 times..but not every time. Thoughts?

Title: Re: High Rpm, no acceleration when pulling tubers
Post by: Rich_V174SS on July 05, 2010, 05:32:02 PM

Sounds like you've spun the hub in your prop. I would try a different one and have the prop re-hubbed by a reconditioning shop.

Title: Re: High Rpm, no acceleration when pulling tubers
Post by: Rosscoe on July 06, 2010, 08:30:29 PM

Erik
Did this issue go away after out of the weeds and did it go away when not pulling a tube? Didnt even seem to notice there was a tube behind it a couple of weeks ago when we were out.

Title: Re: High Rpm, no acceleration when pulling tubers
Post by: not2worried on July 07, 2010, 06:37:02 PM

I didn't that much of a chance to check. Without the tube it was not there for sure. It seemed to be mainly in the weeds. Plan to try again this weekend. It was only a few times. and pretty much right after each other.

Title: Re: High Rpm, no acceleration when pulling tubers
Post by: Eric_Michael on July 08, 2010, 02:34:59 PM

Just an odd thought... 

Maybe this is simple prop cavitation.  The extra drag of the tube is causing the prop to cavitate easier.  This is not necessarily a bad thing, especially with a 2-cycle motor.  It allows the motor to get into its power band sooner instead of struggling at a low RPM.

I have two props that I use.  The big wheel has been cupped so it cavitates easily.  It keeps the motor from lugging down when starting out.  The little wheel is not cupped and will launch the boat like a bullet (although I don't like to stress the transom that much).  It will bite the water better which makes it suited for the lower speed towing.

As an aside...  The big wheel will hit 61mph or so at right around 5000rpm.  The little wheel comes really close at a 59mph, and 5500rpm.

(Sorry, memory eludes me on the numbers for each prop.  I will have to check if someone wants to know.)

-Eric

Title: Re: High Rpm, no acceleration when pulling tubers
Post by: Hyperacme on July 08, 2010, 03:52:08 PM

Might just have been weeds wrapped around prop ?

Title: Re: High Rpm, no acceleration when pulling tubers
Post by: Rosscoe on July 09, 2010, 01:08:30 PM

Hopefully it was just weeds. Sure sounds like it if it went away. Next time (if there is one) stop right away and lift the motor and check.