I replaced the port outdrive in late October and still in the break-in period. I took the boat out today to rack up a few more hours and as I approached 3000 rpms, the port engine started surging, up to about 3400 down to 2800 with bad vibrations. Dropped rpms to 2800, rock steady, everything is fine! At this point I'm almost freaking out, have a spun out the prop (not probable, I haven't hit anything) is the outdrive bad, is the shaft from engine to the outdrive or u-joints going bad? What in the world is wrong!!! Drop engines into neutral, walk back to the swim platform to visually inspect the outdrives and what do I see, a small stick wedged against the swim platform support. As I go to remove it, the small stick becomes a 3' long branch about 1-1/2" in diameter. Inspect the branch, no chunks from the prop, in fact, the branch was making no contact with the outdrive. The lighbulb goes off. As I increase speed, the flow of water over the branch forces it lower into the water, DIRECTLY BEHIND THE PROP. Science in action, the stick was interrupting the "prop wash" (proper term?) and causing cavitation. Remove the stick, all is well, 5 hours into break-in, another 5 to go...
The Stick...
- Thread starter aholst1
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- Jan 1, 2000
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At least it was a small one. I pulled a 20' , about 4"x14" and weighing a few hundred pounds out of a main channel today. Was floating vertically with only about 6"of a sharply angled end sticking out of the water. Could have made for a VERY bad morning for a boat or ferry. NOT the kind of twig I'd want stuck under (or through) the boat.
Long time ago. When I was still in a learning curve with my previous boat, (27' Dancer) suddenly lost my steering function. Wheel would only turn a little in each direction. Using reverse and making a big arc I was able to navigate the boat out of the channel. (steering with twin outdrives wasn't something I was aware of yet)
I set the anchor, and although I really was dreading getting in the river and feeling around under the swim deck & outdrives, I didn't see an alternative.
Hanging on to the swim deck with one hand and feeling all the slimy stuff with the other, I finally felt something that didn't seem right.
That 2x4 was about 6 or 7' long. Had gone right under the keel and wedged right against both outdrives and transom. Slid sideways when I pulled on it, and floated on down the river.
It's the stuff you can't see that gets ya.
I set the anchor, and although I really was dreading getting in the river and feeling around under the swim deck & outdrives, I didn't see an alternative.
Hanging on to the swim deck with one hand and feeling all the slimy stuff with the other, I finally felt something that didn't seem right.
That 2x4 was about 6 or 7' long. Had gone right under the keel and wedged right against both outdrives and transom. Slid sideways when I pulled on it, and floated on down the river.
It's the stuff you can't see that gets ya.