I’ve had a slight vibration felt on the flybridge at various RPMs. After haul out I had the prop shafts checked for trueness and they are. Based on the survey I am also having the cutlass bearing‘s replaced. I had the propellers pulled and sent to Airmarine in Chicago to have them scanned. Those props are 32X29. Airmarine said there are various issues with them. What’s of more concern to them is the data I provided:
WOT RRM 2250 Specs say should be 2350
18 MPH
Boat is lightly loaded; 80,000lbs.
All original, rebuilt and tested by RPM in Lauderdale injectors, no smoke and 3500 original hours.
The boat originally came with 32X32 propellers which I have in the generator room. Called the previous Captain and asked why the change in propellers? He said that the previous owner wanted to unload the 8v92TIs a little bit. He mostly ran the boat at hull speed not wide open throttle. They also carried a lot of stuff so the boat was heavy.
I’m going to have the 32X32 propellers scanned as well. The big question is which propellers should I put back on the boat? It sounds like it might be costly to true the 32X29 propellers. I have no idea what the condition of the 32X32 propellers are. Other than a slight vibration the boat isn’t broken. Because of the high hours on these motors I would like to baby them as much as possible. I run the boat mostly at 1200 RPMs but every hour or just before we go back to the barn I’ll run her up to the pins to get her on plane and then back down enough to keep her on plane for 5 to 15 minutes. They run fantastically and I’d like to keep it that way. So which propellers would be ideal to put on the boat, 32x29 or the original 32x32s?
Welcome to the Hatteras Owners Forum & Gallery. Sign Up or Login
+ Reply to Thread
Results 1 to 3 of 3
-
10-24-2020 09:10 AM #1
Propeller Question For The Brain Trust
Last edited by Sadey; 10-24-2020 at 10:20 AM.
Dave & Trina
Benedetto
1989 60MY HATDK310
Sturgeon Bay/Ft. Lauderdale
-
Re: Propeller Question For The Brain Trust
You want to be able to reach max loaded spec RPM. I would take them down to 32 x 28.5
Sky Cheney
1985 53EDMY, Hull #CN759, "Rebecca"
ELYC on White Lake--Montague, MI
-
10-25-2020 08:46 AM #3Senior Member
- Join Date
- Jul 2013
- Posts
- 1,188
Re: Propeller Question For The Brain Trust
Yeah, going to 32x32 would be going the wrong direction. Couple questions for you...
- Is your bottom clean?
- Are your fuel filters fresh/clean?
- Are your air filters fresh/clean?
- Getting any smoke?
- Are you getting full throttle travel? - this is the cause of a LOT of bad WOT numbers. Verify with your hand on the throttle lever ON the engine, at the dock that wot at the helm actually putting the lever in wot at the engine.
- Are the engines mechanically sound in every other way? (turbos, blowers, injectors...etc)?
If you can check all those boxes then I'd suggest taking the props down a little in pitch if they can. If your 32x32's are in better shape than the others the shop may be able to take them down in pitch or diameter. A good prop shop should be able to look at your numbers and tell you how much pitch/diameter needs to be taken out.SOUTHPAWS
1986 52C Hull #391 8v92TI
PENSACOLA, FL