2001 Carver 396 Prop size?

[cliff36909]

Hello All:

I'm in the process of purchasing a 2001, 396 with the Cummins 6BTA-5.9-M3 370 hp (821 hours). Can anyone with the same boat tell me what the stock size prop should be? I believe the boat maybe over propped as it will only reach 2800 rpm at WOT and I have read that the boat should reach at least 3000 rpm at WOT. If anyone can give me some feedback that would be fantastic as I'm looking to have the boat surveyed in a couple of weeks and I can look at the prop numbers when the boat is in the air.

Thanks,
Cliff

[buster53]

First things first...make sure the bottom is nice and clean before thinking about changing props. It doesn't take much bottom growth to kill a couple hundred RPM's.

[mjk1040]

Prop size will not get you 200 rpm's, but 1 or 2 degrees of less pitch will. If you go to the carver yacht site I do believe you will find the correct OEM prop size and pitch.

[KyleR]

I realize this is a nearly 3 year old thread - but does anyone know the answer of what the stock prop size is for a Carver 396 with twin Cummins 5.9 6BTA engines? Obviously can't go to the carver yacht site anymore! I can only reach 2700 rpm on a 2002 396 with this engine configuration so I am curious what the stock prop should be. It currently has 24" x 28.2 pitch. At least that is what is stamped on each prop.

Thanks in advance!

[km1125]

It's too bad the OP didn't come back and update after his survey on what that boat had, whether they were proven to be stock or not.

Did you rule out everything else that could be causing the performance issue? Folks don't typically put a larger-than-stock prop on these kind of boats so I would think that an oversized situation is pretty rare.

[KyleR]

Did you rule out everything else that could be causing the performance issue? Folks don't typically put a larger-than-stock prop on these kind of boats so I would think that an oversized situation is pretty rare.

Not yet - so many possibilities for not getting to rated RPM: throttles need adjustment, gages read inaccurately, aftercoolers excessively dirty, turbochargers have excessive wear, dirty fuel filters, dirty air filters, wrong size props, and so on and so on!

I just ran across this thread on prop size and thought maybe I'd get lucky and find out if the current props are OEM spec. At least that would be one of the above variables I could eliminate before moving on to the more involved troubleshooting.

Thanks for your reply!

[bud37]

One other thing to consider......It is possible the original dealer taking delivery may have done a sea trial and propped the boat accordingly in the original PDI, that may have been a change from the ones delivered on the boat from Carver.....over the years these boats have an awful habit of getting heavier, much like we do.. ..

[km1125]

Do the easiest things first and rule them out... ESPECIALLY regular maintenance items. You need to "reset the clock" on maintenance items when you purchase a boat. Even if the previous owner said those maintenance items were "recently done", that should mean pretty much NOTHING to a "new to you" boater. Things like impellers, fuel filters and oil changes should be something on the VERY SHORT LIST when you take ownership, so that you KNOW FOR CERTAIN when they were in 'like new' condition.

If there is ANY doubt that the air filters are not CLEAN then that would be my A#1 priority on a diesel engine. They need LOTS of air. VERY easy to do and virtually no cost involved. Then move on to harder stuff.

[KyleR]

Source of the post Do the easiest things first and rule them out... ESPECIALLY regular maintenance items. You need to "reset the clock" on maintenance items when you purchase a boat. Even if the previous owner said those maintenance items were "recently done", that should mean pretty much NOTHING to a "new to you" boater. Things like impellers, fuel filters and oil changes should be something on the VERY SHORT LIST when you take ownership, so that you KNOW FOR CERTAIN when they were in 'like new' condition.

If there is ANY doubt that the air filters are not CLEAN then that would be my A#1 priority on a diesel engine. They need LOTS of air. VERY easy to do and virtually no cost involved. Then move on to harder stuff.

Thanks for your reply! You are preaching to the choir!!

[KyleR]

As a follow-up to the question about prop size....I ran across the original dealer's "pre-delivery checklist" for our 2002 396 with twin Cummins 6BTA (370hp) - dated 3/28/2002. Pretty cool stuff...

Anyway, the boat came propped from the dealer with 24" x 29p props on a 2" shaft. It developed 3101rpm port and 3099rpm starboard under load on the sea trial which is exactly what you want to see - approximately 100rpm > rated rpm (rated rpm = 3000).

Hope that helps someone!