backing up

[rowermike]

I have what may seem to be a rather curious question. I need a prop that backs up better than the one I currently have. I coach crew (competitive rowing). I recently started using an old 1983 Merc 9.8 2 stroke. It is running like a champ and pushes my launch along quite briskly. However with the current stock prop it backs up very poorly.
As a coach I am frequently required to slowly move around and approach very near to the shells. The need to backup firmly and with control is important. The current prop goes forward great but seem to slip a lot in reverse. The hub does not appear to be slipping.

Any suggestions would be appreciated.

 

[steelespike]

Re: backing up

Welcome,
Motors with through hub exhaust sometimes have a difficult time reversing.
The exhaust causes ventilation.
If your running a 2 blade a 3 or 4 blade may help.
It does appear you will have a difficult tiime finding a prop.Iboats doesn't even list the motor.
There are props with reverse cup but not for small motors they are internded for houseboats
and such. A prop shop may be able to add reverse cup if they have heard of it.
If you search the net you may find a 3 or 4 blade.

 

[rowermike]

Re: backing up

Thank for the suggestions. Motor currently has a 3 blade prop on it. If I can't find a better alternative before the end of the rowing season I'll probably send it some place to have it repitched. In the meantime I'll just have to be more cautious.

 

[Silvertip]

Re: backing up

Don't spend hard earned money repitching a prop that won't make it back up any better. Look at the blades!!! They are designed for efficiency during forward propulsion and are very inefficient in reverse because the blades have a scimitar shape to them. The only prop that will work reasonably well in reverse is one that has blades that aver very uniform in shape looking at the prop from the hub. The blades will be large and very rounded much like looking at a four leaf clover (only a three blade would be a three leaf clover). These props will have very little "sweep" to the blades.