Boating Straight

[Marin]

I know people with single engine CHBs and none of them have ever said anything about wandering being a characteristic. Not that I've asked them specifically, but we've had conversations about their boat's handling and I would have thought they'd have mentioned it if it was a problem.

I don't believe prop walk is a factor--- or very much of a factor--- when a boat is moving forward at cruise speed. We chartered a single-engine GB before buying our own and it had a rudder indicator and when the boat was tracking dead straight (with no wander other than what the waves or current swirls did) the indicator was right on "0."

It sounds to me that, for one reason or another, your steering system is not up to par, either because of play in the system, air in the hydraulic lines or actuator, or the modified rudder.

 

[Tom.B]

You really should stop comparing my little Senator 35 to Grand Banks, Eagle, or other "nice" brands of trawlers. While I am not an expert, I have seen these boats out of the water and compared the size of their gear to the size of mine (yes, we are still talking about the rudder... yes... on my boat... yes!... the fiberglass thing in the water

) and for a similar size boat, there is a big difference. I am not discounting any of the factors you suggest, I am just saying there is a big difference in running gear.

So you are saying prop walk doesn't affect steering at cruising speed? That goes against every fiber of my being to think that.

 

[Penta]

Gonzo - with a hydraulic system you want to be certain that you do not have an internal leak through one of the valves. We have a Wagner system on Penta and she would not steer straight or hold a course for any length of time. I finally realized that when trying to steer a straight course that the wheel would gradually creep around and not stay centered. If I were to put the helm hard over and hold it there the wheel would slowly creep around and not come up hard as it should. When I pulled her for the re-fit I carefully checked the system and found that when the upper helm was disconnected and the lines plugged the steering was tight and would not "bleed" off when held hard over for a fairly lengthy period. Further inspection found that there was a fair bit of pitting in several of the valve chambers in this pump so I sent it off to a shop for overhaul. On re-installation the helm now will come up hard (almost feels as though it is a mechanical stop) and stay that way until you get tired of holding it there.
There are several "bypass" leak possibilities in a Wagner system that if any one should start to fail you can end up with a wandering helm.
Just a thought but one that is real easy to test and show up a fault that you may have not recognized.

Good luck

John Tones "Penta"
Sidney, BC

 

[Tom.B]

I'll start the search when we are on the hard in two weeks. I'm sure the manual has the bleeding procedure in it. At least I hope so.

 

[Marin]

GonzoF1 wrote:

You really should stop comparing my little Senator 35 to Grand Banks, Eagle, or other "nice" brands of trawlers.

So you are saying prop walk doesn't affect steering at cruising speed? That goes against every fiber of my being to think that.

I believe CHB is considered to be a "nice" brand of trawler.* You said that single engine CHBs are supposed to have "wandering" steering.* I haven't heard that they do.

Just because a boat isn't a "name brand" doesn't mean it can't steer properly.* Over the years I've known people with all sorts of single-engine boats, from inexpensive Bayliners to Tollycrafts to Grand Banks to lobsterboats.* No one that I've met has complained about poor steering being inherent to their brand.* There is a fellow on our dock with a 36 or so foot single engine trawler made in Taiwan.* The brand is one of those double Chinese names--- Lin Hwa or something like that--- problably the name of the yard that made it.* It's a run-of-the-mill "Taiwan Trawler," and he had a tracking problem that turned out to be a faulty rudder actuator.* He replaced that and his boat tracks right on the money now.

I don't know anything about Senator boats.* But I would be very surprised if they were built or designed so poorly with such cheap componentst that the steering system was incapable of keeping the boat on track.* If the boat truly is that bad, I would assume that this same lack of quality or good design would show up everywhere else thoughout the boat.* Does it?

Propwalk is a force that is generated by the act of rotating the prop blades through* water.* It is strongest when the boat is stationary because there is no other force opposing it other than the resistance of the hull to move sideways.* When the boat is moving at cruise speed, there will still be a degree of this force generated but it will be nothing in comparison to the thrust coming off the prop and the resistance of the hull, rudder, and keel (if your boat has one) to the yawing force of propwalk.

*


-- Edited by Marin on Monday 1st of November 2010 12:12:19 PM

 

[Phil Fill]

So if you just held the helm/rudder a little to one side, would that keep the boat tracking straight?* If so just reset the rudder indicator so the rudder counters the prop.* Both of my OB engines have a zinc skak which is slightly off center to counter the prop.

Do you constantly have to turn the helm to make the boat steer straight?* Is so it sound like a leaky valve.
*
To me a boat is made up of a number of different system of which the helm and rudder is just one of them, so brand name of the boat does not mean that much.**

If the helm/hydraulic has 3 lines*its simple as I menstioned before.* Just turn back and forth to the stops and hold, while filling the top*helm pump.

To me it looked like a big tire iron and did not have a clue what it was for!* I thought it might be to turn over the DD 671.* Did not dawn on me that it might be a till on a power boat?**

I had the helm rebuilt also, the one way little valve cost a couple of buck the labor was a couple hundred.* ****************
*
*


-- Edited by Phil Fill on Monday 1st of November 2010 03:33:00 PM

-- Edited by Phil Fill on Monday 1st of November 2010 03:37:05 PM

 

[Marin]

Phil Fill wrote:
Both of my OB engines have a zinc skak which is slightly off center to counter the prop.

From what our Yamaha dealer tells us, the reason you have to skew the zinc trim tab is to counter the torque of the vertical engine which wants to rotate the whole motor to one side (opposite the direction of crank rotation) and thus steer the boat that way.* Angling the zinc anode trim tab the other way counters this force.* I don't believe it has anything to do with prop walk, which with a prop the size of the ones on most outboards is going to be negligable.

*


-- Edited by Marin on Monday 1st of November 2010 03:39:59 PM

 

[RT Firefly]

Hiya,
** OK, this "Boating straight" thing has been going on for 66 posts now.* I'd just like to add as an alternative VOTE YES ON PROP 19 tomorrow!!!!!!!!!

 

[Phil Fill]

It could be the engine, I was told the prop, but either case its use to count what ever the force.* **

 

[Tom.B]

So if you just held the helm/rudder a little to one side, would that keep the boat tracking straight? --- Yes it will, but if it drifts from some external force or just because things on trawlers happen so slowly, it takes a lot of corrections and over corrections to get it back. But it does NOT take constant pressure on the helm to keep the rudder pointing the direction I set it. (Unless it's moving and I don't know it)

Do you constantly have to turn the helm to make the boat steer straight? --- Generally speaking, yes.

 

[Marin]

GonzoF1 wrote:

Do you constantly have to turn the helm to make the boat steer straight? --- Generally speaking, yes.

That sure sounds like slop in the steering system.* Air in the hydraulic system, a worn out rudder actuator, mounts for the rudder actuator that are letting it physically move when the rudder or sterring system put pressure on it, etc.

The only other thing that comes to mind we've disussed already, and that is the modifications to the rudder have made it too sensitive, over-balanced, whatever you want to call it.

But... a question for those of you with hydraulic steering.* Can you backdrive it?* In other words can you apply a turning force to the rudder (by hand if out of the water, by the waterflow past it in the water) and have the steering system move and turn the wheel at the helm?* Beacause if you can't, then even if Gonzo's modified rudder was out of balance, it would not move on its own because you can't backdrive a hydraulic steering system.

Which if this is the case leaves slop of some sort in the steering system as his problem.

*


-- Edited by Marin on Monday 1st of November 2010 04:14:59 PM

 

[Forkliftt]

Gonzo,
i just read over all 8 pages of posts to be sure that this wasn't mentioned- but I remember having to oversteer our Capilano system after we got our boat- very annoying. Turned out that the small knob beneath the steer wheel shaft (more turns /less turns) needed to be screwed in to give a quicker response to an adjustment. Worked great afterwards.

 

[Datenight]

Penta,

I have had a similar problem with my Wagner 700 for the 12 years we have had the boat. Everyone including Wagner reps say bleed the system. I have done it and had it done with no real improvement.

Was the pitting easy to see once you had the helm apart? Where did you send it and how much was the service.

Thanks,

Rob
37' Sedan

 

[Tom.B]

Forkliftt wrote:

Gonzo,
i just read over all 8 pages of posts to be sure that this wasn't mentioned- but I remember having to oversteer our Capilano system after we got our boat- very annoying. Turned out that the small knob beneath the steer wheel shaft (more turns /less turns) needed to be screwed in to give a quicker response to an adjustment. Worked great afterwards.

Interesting. When I go down this weekend, I'll look in the book and see if there's one of those.

Oh... And thanks for reading all 8 pages

-- Edited by GonzoF1 on Monday 1st of November 2010 08:23:30 PM

 

[C lectric]

A good start would be to get the steering cylinder rebuilt. They are usually quite simple affairs. If the seal on the piston is leaking from one side to the other it will allow the boat to drift as the rudder can move without any input from you. The oil can leak from one side to the other. There may not be any outward sign such as a leak - it is entirely internal. If it's like my cylinder it is simply an o ring to replace.
Bleeding will not help this.

You might test for this by, at the dock and tied, crank the wheel over hard one way and then the other way.
Hold those positions with pressure. The wheel should stop or creep very,very little. Otherwise there could be leakage at the piston. Yes there are other sources but this is usually easy to check and repair.



-- Edited by C lectric on Monday 1st of November 2010 08:29:24 PM

 

[Tom.B]

Marin wrote:

*
GonzoF1 wrote:

Do you constantly have to turn the helm to make the boat steer straight? --- Generally speaking, yes.

That sure sounds like slop in the steering system.* Air in the hydraulic system, a worn out rudder actuator, mounts for the rudder actuator that are letting it physically move when the rudder or sterring system put pressure on it, etc.

Sure. I haven't discounted that as a problem. But it CAN be set to go straight for a little while if I can find that infinitely small sweet spot. Maybe for a minute or two if I am lucky on a calm day. Then, even just a little adjustment to port will cause it to start a pretty big, allbeit slow, turn (bigger than I like anyway) and it takes easily a half or full turn to starboard to stop it... and back to port to catch it. Then the back and forth gets going again and I eventually have to work it back to the sweet spot. But it takes a few minutes each time. It's frustrating. Sometimes I feel like I have to keep my eyes and hands completely focused on driving (even on a 5-mile wide river) to the point I can't enjoy the world going by... Even at just seven knots! That is why I bought a trawler in the first place.


-- Edited by GonzoF1 on Monday 1st of November 2010 08:35:19 PM

 

[Codger2]

GonzoF1 wrote:"Then, even just a little adjustment to port will cause it to start a pretty big, allbeit slow, turn (bigger than I like anyway) and it takes easily a half or full turn to starboard to stop it... and back to port to catch it. "

Sounds like a classic case of "air". The system should be "thoroughly bled" by
someone who is expert at bleeding. I know too many guys who attempt it but really
don't know what they're doing.

*

 

[Penta]

Gonzo - I still think that there is a very good chance that you have an internal leak in the hydraulic system - helm pumps, check valves or just maybe - is there a bypass valve at the steering ram to allow the system to be bypassed and use a steering lever/tiller for emergencies - great place to have a bypass leak! Larger rudder may be putting a bit more pressure on the system causing more of a leak.
First thing that I would do is turn the helm hard over and hold it there watching for the helm to slowly turn instead of staying hard like it was on a mechanical stop.

Datenight
The repairs to a hydraulic steering system are not involved especially the likes of Wagner or Capilano. Any good hydraulic shop that repairs farm or construction hydraulics should be able to do a first class job. In my case when I tore the helm pump down and pulled the pistons it was easy to see the corrosion scoring on the walls. The shop honed them out and made new pistons and the system has been fine for over 10 years now. Cost, if I remember right was about $200.00 and only took two days to have it back.

Hose v/s copper tube steering lines - either will work fine PROVIDED the hose is rated for hydraulic fluid and will stand the pressure in the system. With copper there is no worry that the lines are going to bulge with pressure and if installed properly will give many years of service. The ones in Penta are now coming up to 50 years old and after a good inspection I am not going to replace them - there is no reason.

Adding fluid - be very careful that the hydraulic fluid you add is compatible with what is in the system now - draw a small amount out of the system and add some of the new into it and see if it mixes or if it turns to "gummy snot" which some will do. That sure makes for poor steering

Hope this helps
John "Penta
Sidney, BC

 

[Datenight]

Thanks Penta,

We have several good shops around here. I'll pull the helms and give it a try. Nothing to loose!

Rob
37' Sedan

 

[reefdrifter]

My 34 Ft Marine Trader also wanders a bit from side to side. I removed the dead AP when I got the boat so at this time I have to hand steer. Not a real problem but you do have to stay on your game for the most part especially in tight quarters. I don't mean to hijack this thread but my big question for you guys is this. Do all trawlers require many turns from rudder stop to rudder stop? My system is hydraulic and from the rudder at (generally) the center position to hard right or left stop is four full turns each direction. That is eight turns from stop to stop. WOW I'm getting tired of turning the wheel just thinking about it and writing this post!!! Is that number of turns about standard? Is there any way to change the system to steer more positively with fewer turns of the wheel?

 

[Marin]

reefdrifter wrote:

Do all trawlers require many turns from rudder stop to rudder stop?

Depends on the system. Our cable-chain steering system is three turns lock to lock.* We've manually steered the boat for the twelve years we've owned it and making course changes or corrections is generally a matter of an eighth of a turn or less.

Maneuvering is very easy and if an occaion arrises when we have to go full lock to full opposite lock it's just a matter of putting a finger on the king spoke and rotating the wheel three times--- there is hardly any resistance so it's easy to do with one finger.


-- Edited by Marin on Monday 15th of November 2010 11:49:26 PM

 

[FF]

On our Hyd system the engine supplies steering pressure, the wheel is just the control for a valve.

Its 40 inches in diameter , but easily could be 5 or 10.

2 turns lock to lock .

Steers just fine

 

[carvendive]

I have a twin screw FHB 38 1985. It wandered just like yours. I checked all the hydraulics and found no leaks. Then I checked and found that my fluid was low so I filled and purged the air. That made it a bit better. Then I turned the knob just below the wheel and got it even a little better at keeping course but it would still drop off.

We pulled the boat to have the fuel tanks cleaned and have some thru hulls replaced. While it was out of the water for some reason I went to the rudders and pushed on them. Bingo I could push one 15 deg off line from the other. (Our diver could have checked it in the water.) Once we dug into the problem I learned of several problems with my steering system.

First, the connector rod (at the rudder posts) had a ring on it that had elongated accounting for some of the play. I had a new one welded on.
The previous owner had (maybe) never greased the shaft bearings. Ive never seen bearings this bad. I replaced them.
The tower for the rudder post was a (sort of) upside down U shape with flat legs at the opening of the U that attached to the hull. Two of the attachments were broken and this allowed for some flex in the tower.

Now that the boat is back in the water it steers like a dream. When Im in an area with steady current (no swirls) I can let go of the wheel and let it run for periods of time without having to touch the wheel.

Anyway, my advice is to check each and every component in the system. Perhaps have your second mate open up the access to the rudder posts while underway and have a look-see for any component vibration or erratic movement.
-Dave

 

[Tom.B]

Will do.

I actually grabbed the manual for the hydro steering when we were down this weekend. After reading it, it looks like there are a few things I can check. The fluid may indeed be low, but there is no bleeding procedure noted anywhere. Just to keep it the fluid full and the air will work itself to the top eventually. I will check the things you listed as well. I'd really like to solve the issue (if, in fact, there is one to be solved).

We are also on-the-hard for the next 10 days, so when I get down to paint the bottom before our trip to Carolina Beach, I'll run thru a few things with it and see what I can see.

I'll keep y'all posted. Thanks for all the help so far.

 

[Tom.B]

Just arrived at the boat yard at midnight tonight. Before I turn-in, I did a walk around and there appears to be a goodly amount of slop in my rudder. It's a clunky slop, so I'll check the connection to the cylinder tomorrow. We may be onto something. Will keep you posted.

 

[Tom.B]

Found a problem... is it THE problem... I don't know, BUT, the bolt that holds the hydraulic ram to the rudder had... WAIT FOR IT... fallen out. I replaced it for now, but will fix it with a castellated nut in the near future. That, plus the mount for the other end of the ram is not very stable. Which means that I will be better off than before just fixing those two items. So we'll see. I thin that not matter what, it will be WAY better than before.

More to come.

 

[Peter B]

What was connecting it then? How come you had any steering at all? I think you have indeed found something important all right.

 

[Tom.B]

Sorry... I wasn't clear enough about that. The bolt was still there, but the nut had fallen off the underside. It is a lock nut (with the nylon insert), but the material the bolt and nut had to hold together (the piston and rudder) was too thick for the nut to get seated on the bolt. So it fell off. I have replaced it with a longer bolt and new locking nut until I can get a permanent fix for it. (castellated nut and pin)

I'll have pics up later today, I think.

 

[FF]

I can get a permanent fix for it. (castellated nut and pin)

Agree , far better than any ny-lock nut for steering.

 

[reefdrifter]

Here is another steering situation the I have run across today that may help others.
Last Thursday I topped off my steering hydraulic fluid at the upper helm. We went out for several hours and the steering seemed to improve from the typical wandering of before the top off. Today I again added some hydraulic fluid at the upper helm and then checked the lower helm and it seemed full. A couple of hours later I noticed a leak at the lower helm. It looks like it is coming out at the seal of the steering shaft. I had not turned the wheel to create any pressure and I am thinking it is the steering shaft seal just behind the wheel. This is a 1983 Marine Trader so I think the steering mechanisim must be fairly standard. Does anyone know what these shaft seals look like and how to remove and replace them? Where would you buy new ones? If they are just a "O" ring then if I am able to get the old one out maybe I could get one at an auto parts store or maybe Ace Hdwr. Any ideas?

-- Edited by reefdrifter on Monday 22nd of November 2010 07:29:38 AM