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fastjeff
01-19-2007, 06:37 PM
"Hey! It's about time I asked a question for once, right?

A 32 foot cruiser with twin, straight inboards. Late last summer it started pulling to port--one had to keep pressure on the wheel or it would wander off to port. Now, this is a boat with a nice big keel that always tracked straight and true. Beautifully--even with one engine off.

I was a bit apprehensive at haulout, expecting to see something $$$ bent or missing (though the boat was running great). To my relief and confusion everything looked "normal".

Some background: Props are the same as always, the engines are in synch (both to my ears and the Judson unit) the rudders are properly aligned, and the trim tabs are working correctly. No weight shifting has taken place inside, and the twin fuel tanks are fairly even on fill.

Any ideas?

Thanks,

Jeff"

linesix
01-19-2007, 09:04 PM
"Jeff,
You have answered my first six questions.

Have you checked the hull with a straightedge? A hook developing anywhere in the hull could effect the handeling as you are describing. The two most common causes for hull distortion are improper blocking and deteriorating stringers. Check the entire length of the hull, not just in the transom area.

Also, when you checked the rudders did you check the plumb along with the alignment?

Has the boat developed a list to the port when static? I know the boat is hauled now, but you might be able to check for an unusual scum line on that side.

Good luck
Rick"

fastjeff
01-20-2007, 06:01 PM
"Have you checked the hull with a straightedge?

Not yet. I eyeballed it and it looks "normal".

A hook developing anywhere in the hull could effect the handeling as you are describing. The two most common causes for hull distortion are improper blocking and deteriorating stringers.

Deteriorating stringers! Not possible! This is an aluminum boat, thank heavens. I supervised the blocking last year, and it's such a stiff, solid boat I doubt if that would happen to it.


Also, when you checked the rudders did you check the plumb along with the alignment?

No. Good idea. It WAS okay most of the summer, but the rudders could have gotten smacked by all the debris flating on the Bay last summer.


Has the boat developed a list to the port when static?


Dead level (or as level as a Marinette ever gets).

Thanks for some things to check.

Jeff"

Capt William Myers
01-28-2007, 11:02 PM
I would check the rudder stock to steering joint to make sure the port rudder isn't loose. Or the key is backing out. Grab the rudder with a pipe wrench and hold tight wiggle the steering wheel or shaft. Remember the kind of pressure the rudders are under when the water is flowing passed them.So some force to do this test is needed.