View Single Post
Old 11-07-2013, 05:42 AM   #27
TF Site Team
Baker's Avatar
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,995
Originally Posted by orvals View Post
Hello all...
I bought my Californian just a couple of months ago, starting to know her and looking for info like everyone. My HIN is JGM34230M84K, guess is a 34 made in 84. Got the 3208NA, top 14knts at 2400rpms, cruise at at confy 12Kts at 2100rpms, 10gph. I've read here of 14-16 knts on same engines, my Cats run smoke free up to wot, but I get only 14knts. If I can cruise at 14 and top at 16-18, I would never sell this boat! I have not had a chance to check prop size, they are 3 blade. I've read here of factory prop 24X22 4 blade.
What is rated max RPM at WOT for those engines??? I am under the impression based on a quick google search that max RPM for that engine is 2800. If you are only getting 2400 with the power lever firewalled, then you are overpropped and that is not good for the engines...especially if you run them hard which it seems you do. I do believe a 3208NA is more tolerant of being overpropped since they do not deal with the higher temps of turbocharged versions.

To give you an idea. My Cummins 330Bs also have a 2800 max rated RPM. I run them at 2400. BUT, WOT I can achieve about 3100RPM....meaning I am underpropped and the engines are not working as hard. If all I could achieve was 2400 at WOT, my engines would be cooked in about 1000-1500 hours. I do believe a highly boosted Cummins is a bit of different animal than an NA 3208. But you are doing your engines a diservice if all you can get is 2400 WOT. And their service will be drastically reduced over time. It would not be nearly as detrimental if you were running around 1500RPMs. will likely LOSE speed if you take pitch out of your props.
Prairie 29...Perkins 4236...Sold
Mainship Pilot 30...Yanmar 4LHA-STP...Sold
Carver 356...T-Cummins 330B
Baker is offline   Reply With Quote