Finding the correct props for my installation

[Cruiser Malc]

Hi,
I have a Princess 32 (circa 1978) with twin Volvo Penta AQD32A (106 hp), mated to 280 outdrives. I use the boat mainly on inland waterways and I believe that it is over-propped. At present the fitted props are 16x17 and they protrude below the skeg of the outdrives (this has caused prop damage when I hit something submerged on the River Soar.)

Does anyone know what the standard prop would be, or have a recommendation that would best suit the type of use on inland waterways? With the current installation, I'm only revving at about 1100-1200 rpm at river speeds, which means close quarter maneuvering can be tricky.

Any help much appreciated.

Thanks
Malc

 

[oldgit]

H,mm sounds to me if the skeg length may been reduced.Those props are not far away from the correct size.If they were "to big" they would hit the cavitation /exhaust outlet immediately above them.
It is extremely difficult to protect those outdrive props from rocks etc.The skegs will go into a sandy/muddy river bed and then whack anything hidden just underneath surface.
In short everything may be in order.
On my old Princess,kept a spare set of props for my 280 outdrives,they came in handy every single season all the while I had boat.
Towards the end could moor boat,raise leg and do prop swap inside 20 mins.Kept a wooden wedge,a cone bar etc handy for that purpose.
Ps.Steel Development do a quick and decent repair,they must have at least a dozen Lear jets and garages full of Rolls Royces with the money they have taken from outdrive owners of the years.Enjoy.

 

[neale]

N

H,mm sounds to me if the skeg length may been reduced.Those props are not far away from the correct size.If they were "to big" they would hit the cavitation /exhaust outlet immediately above them.
It is extremely difficult to protect those outdrive props from rocks etc.The skegs will go into a sandy/muddy river bed and then whack anything hidden just underneath surface.
In short everything may be in order.
On my old Princess,kept a spare set of props for my 280 outdrives,they came in handy every single season all the while I had boat.
Towards the end could moor boat,raise leg and do prop swap inside 20 mins.Kept a wooden wedge,a cone bar etc handy for that purpose.
Ps.Steel Development do a quick and decent repair,they must have at least a dozen Lear jets and garages full of Rolls Royces with the money they have taken from outdrive owners of the years.Enjoy.

Blimey, haven't you heard of depth sounders a down on the Mudway? ?
I've had out drives for years and never needed to change a prop mid season.

 

[Cruiser Malc]

Thanks for the replies.
Managed to get the props repaired at Castle Marine in Caernarfon (brilliant job and very reasonably priced). I think I do need smaller props so that they are better protected and to get easier maneuverability.

Unfortunately, my depth sounder alarm is goosed so it is sods law that you will hit something when you aren't monitoring it!

Thanks
Malc

 

[oldgit]

N

Blimey, haven't you heard of depth sounders a down on the Mudway? 
I've had out drives for years and never needed to change a prop mid season.

Down here on The Merdeway we navigate by "feel" my tallowed lead line stays in its linen bag most of the time.

All the damage was always done above locks,the upper Medway runs through a sandstone river bed with some impressive boulders lurking within

Gods Own River" aka the Thames is just as bad.
Real clonk clonk moments usually occur when mooring.
Most Thames boaters insist of having as much space as possible twixt their boats at public moorings. ie they are useless at mooring in tight spots.As most of them consider it a dangerous adventure to actually untie and leave Marina ,they go to the nearest public mooring just round the corner ,clog it up until late afternoon,before returning back to marina,jumping into Bentley and driving home.This means that latecomers actually using the navigation have to moor at scary ends of public moorings with prop bashing consquences.

 

[scottie]

Leave them alone
Better chipped prop than killing these engines
They will be overpropped to hold engine revs down they are very old units and parts are like hens teeth

Buy a new depth sounder its cheapest option

 

[Lozzer]

I know I guy in Spain who knows a bit about props... He altered his props with an angle grinder as he reduced engine power. Result is see attached pic.