P32 props

[krbp32]

Hi, newbie here,
Hope other princess 32 owners can help me with propeller selection. I have a princess 32 with twin AQD21a's on 280 sterndrives (2.15-1 ratio) . I took her out on the river for the first run recently , rather slow, noisy and intrusive vibration. After some thought i raised the sterndrives to find the size and pitch of the props. Taking what i guessed to be the part numbers , i entered them into Keyparts site. I was amazed to find they are 15x11. Keypart say original fit would have been 15x13. Lancing Marine kindly calculated they should be 15x15. Have not heard back from an e-mail to Princess. It may be worth mentioning that i hope to do some coastal cruising . So before i shell out the thick end of £400.00 i'm hoping some people on here with the same set up can shed some light. Thanks for any help .

 

[oldgit]

Hi, newbie here,
Hope other princess 32 owners can help me with propeller selection. I have a princess 32 with twin AQD21a's on 280 sterndrives (2.15-1 ratio) . I took her out on the river for the first run recently , rather slow, noisy and intrusive vibration. After some thought i raised the sterndrives to find the size and pitch of the props. Taking what i guessed to be the part numbers , i entered them into Keyparts site. I was amazed to find they are 15x11. Keypart say original fit would have been 15x13. Lancing Marine kindly calculated they should be 15x15. Have not heard back from an e-mail to Princess. It may be worth mentioning that i hope to do some coastal cruising . So before i shell out the thick end of £400.00 i'm hoping some people on here with the same set up can shed some light. Thanks for any help .

At WOT were the engines reaching (allowing for age/stuff on board etc) the recommended revolutions. ??
The existing props may be OK for your boat. Despite what online sellers websites may say
It is not uncommon however for a boats of certain age to have fitted whatever was lying around cheap at the time.
Ebay is a very good source of s/hand props and a quick look at Steel Developments site could provide refurbished props at sensible money.
Doubt you will get a reply from Princess, anything over 10 mins old will have long fallen off their radar.
On the subject of coastal cruising, hate to be harbinger of bad news but those engines are going to result in some long passage times and you will struggle against strong tides.Ideal for river work tho !

 

[krbp32]

Thanks for the reply oldgit. Have not tried WOT yet as still checking systems, levels & for leaks. Been over 3 years out of water in yard. Have a suspicion it was a charter boat and i understand they tend to govern there boats speed. Yes i'm keeping a close eye on fleabay and everywhere else !
Any princess 32 owners out there...............? ?

 

[oldgit]

Thanks for the reply oldgit. Have not tried WOT yet as still checking systems, levels & for leaks. Been over 3 years out of water in yard. Have a suspicion it was a charter boat and i understand they tend to govern there boats speed. Yes i'm keeping a close eye on fleabay and everywhere else !
Any princess 32 owners out there...............? ?

You need make very very sure indeed that your fuel system is clean.After many years ashore or up river the sediment in the tanks will be disturbed by any wave action resulting in blocked filters followed by an abrupt stop.
You may have more luck finding other P32 owners on the Thames forum or PBO reader to reader..

 

[krbp32]

My tank is V shaped at bottom with drain tap. It's on my list of to do's.

 

[Spi D]

Being 4 cyl 2.1 litre diesels of 75 hp performance (when new) at 4500 rpm, the potential for performance of any sort, is quite modest.

The 4500 rpm is important to reach (clean bottom, normal load), so prop pitch has to matched accoringly. You need to find the max rpm it can reach at WOT and start the calculactions from there.

 

[krbp32]

It's not performance i'm after. The engines vibrate and i think its because they are doing very little work .

 

[Spi D]

Point taken, but only when an engine performs as meant to, can you know that it (and the driveline) is in good order.

Assuming the sterndrives are OK, the mentioned props of course would have an impact on rpm but souldn't cause vibrations unless damaged.

 

[krbp32]

Bit early spi D. I'm no marine engineer, but in my book if there is no or very little resistance then the engine is free to move. Makes sense to me

 

[alb40]

These engines are very old tech and so are noisy and vibrate. In a friends fairline they vibrate horribly but this can be offset a little by having the engines run at slightly different revs so they don't set up a resonance. It's very unlikely the probs are causing the vibrations unless they are damaged, it's just the way they are. They also rev quite high and so that makes extra racket. They won't do more than 8 to 10 knots in one of these boats as there is not enough power to plane.

You may be able to make a difference by using sound deadening around the engine bay but unfortunately they are never going to be a quiet installation. Parts for these engines are getting difficult to find and they have a tendency to get hot and blow head gaskets if pushed hard unless the cooling system is tip top, so I would treat them gently and not expect to go anywhere quickly or quietly.

 

[scottie]

Being 4 cyl 2.1 litre diesels of 75 hp performance (when new) at 4500 rpm, the potential for performance of any sort, is quite modest.

The 4500 rpm is important to reach (clean bottom, normal load), so prop pitch has to matched accoringly. You need to find the max rpm it can reach at WOT and start the calculactions from there.[/QUOTE

Maybe 75 pony power with a following wind and tide and and a wing and 2 prayers!
Never 4500 more like 3500 and often gov down to 3000 realistic power nearer 60

They need to be cosseted not overworked and as spares are gold dust talked nicely to
as I remember the heads were meant to be tightened down after not being run for any length of time
It is an underpowered boat and if you accept that displacement speeds are it you will get the best out of it
15x11 props do seem light
Dia is power/engine revs and pitch is boatspeed so it seems that some one has accepted lower boat speed but this could be due to older boats being heavier this slowing the boat
The props came in at least 2 boss lengths the long boss had a bigger blade area