Propellers

[outtoc]

hello: i have a 2000 carver 450 voyager pilothouse purchased in 2016.
volvo tamd74p 480 hp ea. zf 280-1 2.27:1 transmissions
can anyone with the same boat tell me what your prop size is.
carver tells me this boat left factory in 2000 with 28 x 34 props
i purchased the boat from the original owner.
the props from the orig owner are 28 x 30.2 (4 inches less pitch.)
i talked with the orig. owner and he can not remember and does not know why
i am only traveling 15 to 16 knots at 2200 RPM after talking with carver and
looking at the boat specs i should be traveling more like 20 knots and
carver does agree. my WOT should be 2600 rpm and i am getting
2625 to 2680 both engines.
if anyone could give me some feedback it would be great
thanks, john

[Alaska 530 Voyager]

Hi John. While I do not have the exact boat as you, I am speaking from experience having dealt with Volvo diesels. One issue that TAMD Volvo diesels have, is that they lose performance in a drastic manner as the charge air coolers start to plug. Our TAMD Volvos are not common rail and they burn very dirty compared to the newer ones. In addition, we don't have closed crankcase ventilation systems. Our crankcase gases are simply filtered and then go to Atmosphere. It is then drawn in through the turbo intake and eventually fouls the charge air cooler. This is the biggest source of power and performance loss that I have found on a Volvo TAMD. Owners tend to prop down to make up the difference. In addition to all of that, TAMD's don't really like today's diesel fuel. I run "Howes" supplement in mine and gain a very significant amount of performance. I would definitely recommend looking at the maintenance that has been done to them. Sounds to me like they are possibly low on power due to an issue like what I've mentioned. While it's definitely normal to pitch a factory prop down, that does seem excessive and seems to me that you should be over-revving even more than you are. Just some stuff to think about. Good luck, Dave.

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hi dave: thanks very much for the feedback. i am in ct. i will be sure to pass this along
to my mechanic when i have him scheduled to do some service on the boat in march.
thanks again,
john

[seabreeze]

I have a 2005 45 voyager with your same engines and transmission.
I just replaced both props and went with the same size on boat.
my new props are 28x32.4 4 bld nibral zf 0.75 ear
at 2200 rpm I run about 20 kts, wot 2650 about 26 kts

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thanks seabreeze. that's great info. fyi my boat had a lot of bottom paint buildup so i had boat hauled and bottom media blasted. going to let it dry out for a while.
looks to be in very good shape. once dry i am going to do any filling and 3 coats of barrier coat then 2 to 3 coats of bottom paint.
had props redone. props are now perfectly balanced and are 28 dia x 31 pitch. hope this fixes my speed problem or at least puts me in the right direction. i need to check my WOT with this pitch of 31. i will continue to pitch the props more as long as i get my 2600 WOT.
what u have (20 knots at 2200 rpm) is what everyone including carver is telling me i should have.
thanks very much again for your input.
john

[Renovatio]

I just had our first large motor boat surveyed
Seems like the boat after years of looking at “Rats”

They all look good in pictures! Wish brokers were more honest, but such the nature of the beast

So the survey recommended reconditioning props. Not exactly knowing if it’s balancing
Runs at even RPMs
Speed is on target
20 knots at 1900 rpms or so


Should or can I wait
Seasons starting everybody’s backed up
Don’t want to tie her up too long and cast off
Very excited

[Viper]

Unless you're experiencing a vibration at a given rpm, I wouldn't worry about it until your next haul out. What you should do between now and then though is record your max RPM at WOT and keep those numbers for when you take the props in. Compare those numbers to the engine OEM's recommended WOT spec and see if you're within spec or not. If not, the prop shop may be able to tweak the props to get you there. Take them to a place that is able to do a "Prop Scan." Most prop shops don't charge for checking the condition of props, at least up my way they don't.

It's going to be a fun summer

[km1125]

If the vibration isn't very bad and it's in the water anyways, you might want to check the shaft alignment and see if that needs any tweaking first.

Also depends on what you plans are for long cruises this year. If there is a vibration and it gets worse at higher RPM, then you might want to deal with it now, or plan to haul the boat for a convenient early-season week and get them done then. If you're mostly doing short cruises then you could easily work around it until next haul-out season.

[Cooler]

Reno - call the surveyor and ask him why he made that comment. Sometimes it is simply a standard suggestion in the report to achieve optimal efficiency. Did the surveyor do the sea trial? Did he/she feel and note any vibration? If no vibration, I would run it for the season and hold off till next haul out. It would be real easy to lose 2 to 4 weeks of season to get no real return. The boat lifts are backed up, and so are the prop shops. On the other hand, IF there is a vibration, then you should get it checked out. Prop & shaft issues get expensive and time consuming. Good luck! er