weird churning noise

1pointofview

figured I would finally ask because i have dealt with it for a bit. Sometimes when the boat is getting bogged down I hear an odd churning noise from the propeller.  Happens sometimes when I am pulling a tube or when boat is loaded. The RPM seems to be around the same spot (normally 4500-5000rpm when I hear it most) but we just seem like we are not getting enough surface speed, no matter how much I try and get more speed by finding calmer water or try and stay a straight course in order to get forward momentum.

I have tried backing down the rpms and then ramping up or adjusting trim down/up.  Seems like once I get the churn noise starts, I have to throttle all the way down and start off again.  Anyone deal with anything similar?

dward0

Checked prop for damage?

1pointofview

no damage.  I took the boat out last week and never had it happen again. I think it has to do with drag due to how many people are on the boat.  I went out last week with only 3 additional people and we never had any issue.  Last few times, I had a total of 9 people.  7 on the boat, pulling 2 on a tube.  I think I may need a different prop that will handle the load a little better. 

cjjjdeck

Sounds like if you are going to be pulling loads like you describe often, then you are on the right track.