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Discussion Starter · #1 ·
A friend & I bought a Cal 33-2 (Hunt design) last Fall. We noticed while motoring home last October that it pulled to port pretty significantly. Just got back in the water this month and the pull to port seems even worse (though not sure about worse). PO says that it always pulled, and has to do with offset shaft and screw. Prop and shaft slightly off center. But this seems excessive. Now, there was delamination in the rudder. We used the drill and fill with epoxy method (I know it's not ideal but we'll see if it needs a rebuild next winter). When the Yanmar is at 2300-2500 and you let go of wheel, the boat will quickly pull to the left and soon be heading at a 90 degree angle and turning. That kind of pull can't be normal (note: doesn't pull under sail, it's definitely prop related). My question is: if the rudder is a little mishapen, and you could see a bulge in one small area if you really look carefully, although slight, would that worsen the pull, especially if the bulge were on the opposite side of the way it pulls (more resistance there, less on other side...)? Or could there be other causes? Boat does have autopilot, but we've checked that it's disengaged. Also, quadrant and cables look good, have the right tension.
 

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There are boats that have this tendency. I have a 1996 Catalina 28MKII, and it does the same thing. Take your hands off the wheel at cruising speed and you go into a spin. The best I could learn is that it's how the prop interacts with the rudder on this particular model.

The pull to left becomes more pronounced as RPM increase.

And, just like your boat, the effect is absent under sail.

So, it could be that some aspect of your boat's design is at issue, or there is a defect in the prop and/or rudder. I think the fact that it does not occur under sail is significant.
 

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run the boat up to speed and the cut the power and coast if it only turns during the power on then the prop thrust is pushing on the rudder was on a delivery when the auto pilot would cut out every so often. every time the boat would take a spin thought is was the autopilot turning the boat but found out it was not it had an off set prop.
 

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I have seen a few boats with a trim tab inside the rudder that was adjustable. This may be an option, but it comes with a host of other difficulties.
 

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I've had my Cal 33-2 for 12 years. There is some tendency to head to port if I let go of the wheel, but nothing that has bothered me. Don't notice any pulling when steering under power and hands are on the wheel. Friends who have steered the boat under power have never commented about any pulling.

What kind of prop do you have? That can affect it. I have a Martec folder.

Some delamination in the rudder due to water intrusion is not uncommon in boats over 30 years old. Foss Foam made the rudders for Cal and have the plans to make a new one if necessary.

Congrats on the Cal 33-2. It's a great boat.
 

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I've seen that with a number of sailboats. Prop walk causes the boat to pull to port under power. An offset prop counteracts that effect.
 

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My Cal 33-2 also pulls to port under power. The shaft has a fairly sigificant offset.
I wouldnt worry about the pull to port, but I'd be very concerned about the rudder.
Foss Foam in Florida made the original rudder. They have the original molds. The shop is run by the grandson. Fiss Foam in Cali also makes the rudders and another company in Cali has a newer design .
 

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Any vessel with a right hand prop exhibits prop walk in forward gear which takes the stern to starboard, so the bow goes to port. How fast the turn becomes depends on rudder design and location. I owned a Beneteau 30E which if you let go of the tiller under power immediately spun into a tight circle. Other boats haven't exhibited such extreme behavior, but its a question of degree...

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The Cal 33-2 shaft is offset to port. It would seem to me that would cause the prop thrust to push a bit to stbd when going ahead. If so, that would reduce the tendancy to pull to port, not increase it.

The slightly offset shaft has a big benefit. You can pull the shaft without having to drop the rudder.
 

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There are boats that have this tendency. I have a 1996 Catalina 28MKII, and it does the same thing. Take your hands off the wheel at cruising speed and you go into a spin. The best I could learn is that it's how the prop interacts with the rudder on this particular model.

The pull to left becomes more pronounced as RPM increase.

And, just like your boat, the effect is absent under sail.

So, it could be that some aspect of your boat's design is at issue, or there is a defect in the prop and/or rudder. I think the fact that it does not occur under sail is significant.
My 1991 Mk 1 Catalina28 does the same thing. It was a bit of a surprise when I had the helm under power for the first time.
 

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FWIW, I found this statement online. I don't know the source of the statement. "Increased wheel diameter or blade pitch increases prop walk. Two-blade props walk less than 3-blade props; folding and feathering props walk less still."
 

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Any vessel with a right hand prop exhibits prop walk in forward gear which takes the stern to starboard, so the bow goes to port. How fast the turn becomes depends on rudder design and location. I owned a Beneteau 30E which if you let go of the tiller under power immediately spun into a tight circle. Other boats haven't exhibited such extreme behavior, but its a question of degree...

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The Freedom 28 has a prop shaft offset to stbd. If you let go of the wheel under power it will practically spin in a boat length. With a 2 blade feathering Max Prop, there is virtually no prop walk in reverse. All in all, I like it. And if ever I need to pull the shaft, I won't need to drop the rudder.
 

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Discussion Starter · #13 ·
Thanks everyone for the help. It sounds like it's due to the design, the offset prop. I'm pretty sure we have the original 2-blade prop. Could the pitch be a little too much for the boat and so worsening the prop walk? It sure doesn't feel right, although as I said not an issue when sailing. We do have autopilot if we don't feel like taking the wheel. The good news is that maybe getting a feathering or folding prop with negligeable prop walk might be the solution (besides being an obvious advantage for sailing)?

Eje, you're right to warn about the rudder. After this season we'll probably take it off and bring it to a shop where they can fix it right--which might be less costly than ordering a replacement from Foss, who we've been in touch with btw. Very helpful on the phone.
 

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I was out on my Cal 33-2 this afternoon so thought I would see how much pull there was to port as I didn't remember it being significant at all. After leaving the mooring I motored into the wind at about 5 knots with sails down. Helm felt very light and neutral in my hands. If I took my hands off the wheel, it would SLOWLY turn to port. I could hold the wheel with one finger. So there is something going on with your boat.
It is NOT a characteristic of the boat design.
 

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I had a Cal 33-2 for 5 years and can confirm what JimsCAL has said. That boat had no tendency to pull and was very well mannered both under sail and under power.

-Doug
 

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Discussion Starter · #17 ·
Thank you JimsCAL and DougH for letting me know. Clearly it's not a design issue. But the prop does seem to be a likely culprit. Besides being offset by design, it may be over pitched or oversized somewhat--we won't know for sure until the boat comes out of the water. But here's what we're thinking: we'd like to get a feathering (or folding) prop anyway. If we found one that had minimal prop walk, it might have the advantage of reducing pull to the left. Of course, we have to have the rudder looked at maybe rebuilt. It could be part of the problem (see my initial post).
 

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Doubt it is the rudder as you don't report the issue under sail. Also as has been said previously, the prop shaft is offset to port and will thus push the boat slightly to starboard when going ahead. I agree that the prop is looking like the culprit. I have a Martec folder (no longer available new).
 

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Can you achieve your engine's rated RPM at near wide open throttle ? If you can't then the prop may be pitched too High.. If you can achieve the engine's rated rpm and still have a ways to go on the throttle it may be pitched too low.

I'd take it out and run it up slowly to see if you can get to the engines rated RPM . That would be one test.

What engine do you have? Yanmar 3gm30F ? If so, I believe it's rated to 3600 rpm at WOT. Obviously you wouldn't operate at that RPM but it should be able to get close if the prop is pitched correctly.

Was the transmission ever replaced? A different gear ratio could require a change in prop pitch.
 

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Prop WALK affects the boat in both reverse, where most schools emphasize it, and forward. My O'day 35 with a right handed prop will turn the bow to port in forward, and the stern to port in reverse.

Also, Foss Foam (Foss Rudders – Designer and manufacturer of custom and replacement sailboat rudders.) made the rudders for many boat builders. This fall I had them build and ship a new rudder to me for my O'day 35, and my total cost was less than $3K.
 
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