Strong pull to port while motoring

[HappyMdRSailor]

(woody) It's like driving a stretch of highway many times and suddenly discovering something "new" that had always been there.

Originally Posted by gamayun

Hmm, that has actually been tickling the back of my brain. It is a fairly new-to-me boat, but super strange that it's never been noticeable before. I'm all for the "don't worry about it" attitude, if I really don't need to worry about it, but I'll check out everything tomorrow and will also ask some friends who have motored with me whether they remember anything like this. I really appreciate all the suggestions and the comments about prop walk.

I have kind of a gut feeling this might be the case... Any boat (motoring) is going to turn without helm corrections eventually... Something probably loosened up though to make it more noticeable to you...

[DoubleWhisky]

Originally Posted by gamayun

Hmm, that has actually been tickling the back of my brain. It is a fairly new-to-me boat, but super strange that it's never been noticeable before. I'm all for the "don't worry about it" attitude, if I really don't need to worry about it, but I'll check out everything tomorrow and will also ask some friends who have motored with me whether they remember anything like this. I really appreciate all the suggestions and the comments about prop walk.

If You have a feeling that something is wrong, probably it is. I'm the first to the "don't worry" attitude. But this attitude can give one only sleepless night, believe me
Didn't You feel any unusual vibrations? From the steering, but also from the engine/shaft?
Did You use the same revs of engine as before noticing the problem?

[gamayun]

I went out today and had a beautiful single-handed sail from Richmond to Treasure Island. Saw only 2 other sailboats on the bay. This is the life. Oh. Squirrel. The helm pull...yes, well, it wasn't there. I do notice what I think is a slight port walk in forward, which is confusing, because it seems like it should walk to starboard since my prop walk is to port in reverse. Anyway, just before I left the dock, I checked the steering mechanism. It seems solid. However --- I had recently put away my radar reflector, which was near the computer for the steering. I moved it to the other side of the lazarette and wonder if that could have caused the original problem. Anyone hear of this? Otherwise, I have no idea what made it veer off to port like it did the other day. I'll keep an eye on things though, and will be diligent to find the problem if something starts acting up again. Thanks everyone! You've all been tremendously helpful.

[carstenb]

If it only happened once, it could be because there was an electromagnetic interference with your Flux compass. My boat once turned almost 180 degrees to port while motorsailing on autopilot. Couldn't understand it. I spent days looking for an answer. Sailed the same way again and the same thing happened in the same place.
CAuse - undersea high voltage cables - major interference

[DoubleWhisky]

Originally Posted by gamayun

I do notice what I think is a slight port walk in forward, which is confusing, because it seems like it should walk to starboard since my prop walk is to port in reverse.

Sorry, it is not clear to me...
Does it mean that:

1. Going forward Your bow is turning to the portside?
2. Gaing astern Your stern is turning to the portside?

Or I'm getting this completely wrong???

[boatman61]

Likely fouled something while underway which slipped off when you slowed speed.. lotsa semi+ submerged crap out there.. Or could just have been a flukey current that threw you off..

[StuM]

Originally Posted by boatman61

Likely fouled something while underway which slipped off when you slowed speed.. lotsa semi+ submerged crap out there

That would be my guess too

[Pete7]

Sat next to the tiller pilot with a mobile phone in my pocket. After I recoverd from the gybe the phone was moved down below to the chart table. Lesson learnt.

Pete

Originally Posted by carstenb

If it only happened once, it could be because there was an electromagnetic interference with your Flux compass. My boat once turned almost 180 degrees to port while motorsailing on autopilot. Couldn't understand it. I spent days looking for an answer. Sailed the same way again and the same thing happened in the same place.
CAuse - undersea high voltage cables - major interference

[HappyMdRSailor]

Originally Posted by gamayun

I went out today and had a beautiful single-handed sail from Richmond to Treasure Island. Saw only 2 other sailboats on the bay. This is the life. Oh. Squirrel. The helm pull...yes, well, it wasn't there. I do notice what I think is a slight port walk in forward, which is confusing, because it seems like it should walk to starboard since my prop walk is to port in reverse. Anyway, just before I left the dock, I checked the steering mechanism. It seems solid. However --- I had recently put away my radar reflector, which was near the computer for the steering. I moved it to the other side of the lazarette and wonder if that could have caused the original problem. Anyone hear of this? Otherwise, I have no idea what made it veer off to port like it did the other day. I'll keep an eye on things though, and will be diligent to find the problem if something starts acting up again. Thanks everyone! You've all been tremendously helpful.

OK... I'm confused... I thought you said in your original post that the AP wasn't engaged when you had this "veer to port" issue...

"While motoring (with sails up and without), my boat started pulling to port about 3 seconds after I let go of the wheel. This hasn't happened before. The bottom is clean and the prop looks in good condition. It walks to port in reverse so I assume if it were the prop, it would deviate to starboard in forward, right? Could this have something to do with the AP, though it was not on when this was going on. Could it be the rudder slipping? Any thoughts on where to start looking would be appreciated! "

Now we have all sorts of AP interference posts... ???? Totally different problem... and obviously more possible causes!

Propwalk- Stern to port in reverse means "bow" to port in forward...

[gamayun]

Originally Posted by DoubleWhisky

Sorry, it is not clear to me...
Does it mean that:

1. Going forward Your bow is turning to the portside?
2. Gaing astern Your stern is turning to the portside?

Or I'm getting this completely wrong???

Yes, this is correct. It is a strong port walk in reverse and there seems to be a slight walk to port in forward. There was practically no wind, but current might have affected this. It's not enough now to be that noticeable.

[gamayun]

Originally Posted by HappyMdRSailor

OK... I'm confused... I thought you said in your original post that the AP wasn't engaged when you had this "veer to port" issue...

"While motoring (with sails up and without), my boat started pulling to port about 3 seconds after I let go of the wheel. This hasn't happened before. The bottom is clean and the prop looks in good condition. It walks to port in reverse so I assume if it were the prop, it would deviate to starboard in forward, right? Could this have something to do with the AP, though it was not on when this was going on. Could it be the rudder slipping? Any thoughts on where to start looking would be appreciated! "

Now we have all sorts of AP interference posts... ???? Totally different problem... and obviously more possible causes!

Propwalk- Stern to port in reverse means "bow" to port in forward...

The AP was not on when this was happening. You're right. The reflector shouldn't be the problem if the AP was not engaged. I was grasping at causes.

The light bulb just clicked with "stern to port in reverse/bow to port in forward." That makes sense now

[HappyMdRSailor]

Originally Posted by gamayun

The AP was not on when this was happening. You're right. The reflector shouldn't be the problem if the AP was not engaged. I was grasping at causes.

The light bulb just clicked with "stern to port in reverse/bow to port in forward." That makes sense now

Lightbulb moments deserve a celebration...

How 'bout a Mai Tai ?

[gamayun]

Originally Posted by HappyMdRSailor

Lightbulb moments deserve a celebration...

How 'bout a Mai Tai ?

Funny. I haven't had a Mai Tai since college days. I'll get one this weekend and give a little toast for a nice light bulb moment

Still confused by what happened, though perhaps the best guess is that we had picked up some kelp and it had fallen off before I dove the boat the next day. Ah, so much to learn. At least I'll know what things to consider next time if it happens again, and will know to put it in reverse to loosen whatever is stuck underneath.

[HappyMdRSailor]

Originally Posted by gamayun

Funny. I haven't had a Mai Tai since college days. I'll get one this weekend and give a little toast for a nice light bulb moment

http://www.cruisersforum.com/forums/...ai-118676.html

Still confused by what happened, though perhaps the best guess is that we had picked up some kelp and it had fallen off before I dove the boat the next day. Ah, so much to learn. At least I'll know what things to consider next time if it happens again, and will know to put it in reverse to loosen whatever is stuck underneath.

I'm guessing you are spot on! Happens more than you think....

I was on a buddies 49SO once, and he was surprised when I jumped up and throttled back... (he was at the helm)... He said "what for?" I said "pop her in reverse and you'll see"...

The evidence revealed itself in a few seconds...

[DoubleWhisky]

Originally Posted by gamayun

Yes, this is correct. It is a strong port walk in reverse and there seems to be a slight walk to port in forward. There was practically no wind, but current might have affected this. It's not enough now to be that noticeable.

It is completely normal. Prop walk is significant when going astern and very slight when going forward. It is called "prop walk" for a reason - imagine Your prop "walking" on the bottom.
Your prop (looking from the stern) is turning clockwise on forward, stern is going to starboard and bow to port.
While backing prop is rotating anticlockwise, stern is turning to portside and bow to starboard. On forward move the propwalk is kept low by water flowing over the ruder. When You let the ruder free, the propwalk will overcome the friction in steereing in short time, and boat will start to turn.