Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 05-10-2019, 19:02   #1
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2018
Posts: 118
Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

I've got a catamaran with hydraulic steering. Both hydraulic rams have been rebuilt 3 times, to stop them from leaking, in an attempt to resolve the alignment problem, but the rudders still lose alignment.

There still appears to be a very minor leak on the starboard ram.

Why could this be?

The only way that I can think of is that there is a leak in the hydraulic tie bar (the hydraulic line connecting the port and starboard rams).

Or could there is a pressure issue that causes too much pressure in one of the chambers?

So confused. We've had MultiTech (sub contracted to Signature Marine) and Marine Hydraulics work on this. Well over $7,000 and still no resolution.
__________________

__________________
2006 Fountaine Pajot Eleuthera 60
InsuredApple is offline   Reply With Quote
Old 05-10-2019, 19:09   #2
Registered User

Join Date: Mar 2019
Posts: 316
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Quote:
Originally Posted by InsuredApple View Post
I've got a catamaran with hydraulic steering. Both hydraulic rams have been rebuilt 3 times, to stop them from leaking, in an attempt to resolve the alignment problem, but the rudders still lose alignment.

There still appears to be a very minor leak on the starboard ram.

Why could this be?

The only way that I can think of is that there is a leak in the hydraulic tie bar (the hydraulic line connecting the port and starboard rams).

Or could there is a pressure issue that causes too much pressure in one of the chambers?

So confused. We've had MultiTech (sub contracted to Signature Marine) and Marine Hydraulics work on this. Well over $7,000 and still no resolution.
Do both rudders move freely when disconnected from the steering system? I had a frozen spherical bearing on my Mahe 36 that made one of the rudders really bind, and it would cause the rudders to become misaligned since at times one rudder wouldn't move while the other did.
__________________

redneckrob is offline   Reply With Quote
Old 05-10-2019, 19:17   #3
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2018
Posts: 118
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Quote:
Originally Posted by redneckrob View Post
Do both rudders move freely when disconnected from the steering system? I had a frozen spherical bearing on my Mahe 36 that made one of the rudders really bind, and it would cause the rudders to become misaligned since at times one rudder wouldn't move while the other did.
Thank you for making time to reply.

Yes, both rudders move freely when the hydraulic rams are disconnected from the rudder arm. The boat was hauled out, during the time when the hydraulic rams were rebuilt the 3rd time. That's when I discovered that the rudders could move freely, and the rudder arms destroyed both of the rudder angle indicators; because the rudder arms were not secured.
__________________
2006 Fountaine Pajot Eleuthera 60
InsuredApple is offline   Reply With Quote
Old 05-10-2019, 19:29   #4
Senior Cruiser
 
44'cruisingcat's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 9,081
Images: 69
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

First I'd make a serious effort to ensure the system is completely bled of air. Any air in there could have you chasing your tail for ever.

In the absence of air, there must be a leak in the system, either in the hydraulic link, or in one or both rams.

It would be worth finding if the hydraulic link is effectively getting "shorter" or "longer", ie is fluid leaking out of the link or into it?

Work out if fluid leaving the link would cause toe in or toe out, and which one is happening.

If fluid is leaking in it could only be due to the piston seals in the rams passing.

A leak out could similarly be piston seals, but could also be shaft seals or leaking hoses, connections etc.
__________________
"You CANNOT be serious!"


John McEnroe
44'cruisingcat is offline   Reply With Quote
Old 05-10-2019, 19:47   #5
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2018
Posts: 118
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Quote:
Originally Posted by 44'cruisingcat View Post
First I'd make a serious effort to ensure the system is completely bled of air. Any air in there could have you chasing your tail for ever.

In the absence of air, there must be a leak in the system, either in the hydraulic link, or in one or both rams.

It would be worth finding if the hydraulic link is effectively getting "shorter" or "longer", ie is fluid leaking out of the link or into it?

Work out if fluid leaving the link would cause toe in or toe out, and which one is happening.

If fluid is leaking in it could only be due to the piston seals in the rams passing.

A leak out could similarly be piston seals, but could also be shaft seals or leaking hoses, connections etc.
Very smart, that makes logical sense.

At this point, then, I'd guess that fluid is leaking out of the link (liquid tie bar) because the rudders are closing in, coming together.

Is my thinking right, or am I missing something?

__________________
2006 Fountaine Pajot Eleuthera 60
InsuredApple is offline   Reply With Quote
Old 05-10-2019, 21:40   #6
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2018
Posts: 118
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

This is a rough diagram that I quickly whipped up... just to show our hydraulic system, the bypass valves (green), the liquid tie bar (blue)...

__________________
2006 Fountaine Pajot Eleuthera 60
InsuredApple is offline   Reply With Quote
Old 05-10-2019, 22:07   #7
Registered User

Join Date: Feb 2010
Posts: 252
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Where does the auto pilot fit into this, how does that work in this schematic? Is there a lock/shuttle valve somewhere?.... maybe in the helm pump.
skipperpete is offline   Reply With Quote
Old 05-10-2019, 22:13   #8
Registered User

Join Date: Apr 2007
Location: Australia
Boat: Island Packet 40
Posts: 2,911
Images: 7
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Do the hydraulic lines actually come out the side of the cylinders as you have drawn them?
RaymondR is offline   Reply With Quote
Old 05-10-2019, 22:36   #9
Registered User

Join Date: Jun 2013
Location: canada
Posts: 2,674
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Can you not put a mech tie bar on? The cat I was on last week had one behind the back deck.

Is this how most cats are? Seems they would all be miss aligning over time.
smac999 is offline   Reply With Quote
Old 06-10-2019, 00:41   #10
Senior Cruiser
 
44'cruisingcat's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 9,081
Images: 69
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Quote:
Originally Posted by InsuredApple View Post
Very smart, that makes logical sense.

At this point, then, I'd guess that fluid is leaking out of the link (liquid tie bar) because the rudders are closing in, coming together.

Is my thinking right, or am I missing something?

It depends. On where the hydraulic link is set up on the rams, and on how the rams are set up on the tillers.

You need to look at the whole system and work out what would happen if fluid leaked out of the tie.
__________________
"You CANNOT be serious!"


John McEnroe
44'cruisingcat is offline   Reply With Quote
Old 06-10-2019, 00:49   #11
Senior Cruiser
 
44'cruisingcat's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 9,081
Images: 69
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Quote:
Originally Posted by InsuredApple View Post
This is a rough diagram that I quickly whipped up... just to show our hydraulic system, the bypass valves (green), the liquid tie bar (blue)...

For example, if your hydraulics were set up like this, with the tillers forward of the rudder shafts, and you were losing fluid from the link (blue) line, your rudders would toe out.

However, with the same set up, but with tillers aft, and they'd toe in.
__________________
"You CANNOT be serious!"


John McEnroe
44'cruisingcat is offline   Reply With Quote
Old 06-10-2019, 00:55   #12
Senior Cruiser
 
44'cruisingcat's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 9,081
Images: 69
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Quote:
Originally Posted by smac999 View Post
Can you not put a mech tie bar on? The cat I was on last week had one behind the back deck.

Is this how most cats are? Seems they would all be miss aligning over time.
Probably the majority of cats have some mechanical connection between the rudders.

But hydraulically linked systems can work well. My rudders basically never get out of alignment.
__________________
"You CANNOT be serious!"


John McEnroe
44'cruisingcat is offline   Reply With Quote
Old 06-10-2019, 02:25   #13
Registered User
 
Dave852's Avatar

Join Date: Mar 2007
Location: Tavernier, Fl
Boat: Outremer 50
Posts: 707
Send a message via Skype™ to Dave852
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

You show the valves between the liquid tie bar and and the line going back to the helm. On my boat I also had pressure relief valves installed there. Basically a spring loaded ball bearing that I had cleaned the gunk out and looked fine. But in the end removing them solved my alignment problem. Newer helm pumps have the bypass built in to the pump so any bypass does not affect alignment.
Dave852 is offline   Reply With Quote
Old 06-10-2019, 10:11   #14
Registered User

Join Date: Jan 2012
Location: New York
Boat: FP, Eleuthera 60
Posts: 350
Images: 4
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Had a similar problem on my FP60, was not a hydraulic problem but an auto pilot problem, spent countless hrs. with Furuno tech support, they are great and still things did not work, finally got a marine electrician I know to look at it, reprogrammed the auto pilot commuter from scratch. If you have made any repairs (changing any part of the system) you need to have the main computer to recognize it by reprogramming. It took me a year to get it right...thanks Tony T in NY for your knowledge
MIRELOS is offline   Reply With Quote
Old 06-10-2019, 10:56   #15
Registered User
 
deblen's Avatar

Join Date: Oct 2014
Location: Grand Manan,N.B.,Canada N44.40 W66.50
Boat: Mascot 28 pilothouse motorsailer 28ft
Posts: 1,908
Images: 1
Re: Hydraulic Steering Issue - Rudders Don't Keep Alignment on Cat

Quote:
Originally Posted by InsuredApple View Post
Very smart, that makes logical sense.

At this point, then, I'd guess that fluid is leaking out of the link (liquid tie bar) because the rudders are closing in, coming together.

Is my thinking right, or am I missing something?


Are you sure that the actual rudders are out of line?
Could it be that one of the rudder angle meters or it's sender are the problem? / Len
__________________

__________________
My personal experience & humble opinions-feel free to ignore both
deblen is offline   Reply With Quote
Reply

Tags
hydraulic steering, men, rudder, steering

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale: Edson Helm Steering Pedestal System with Hydraulic Steering System AD 2 Classifieds Archive 0 23-03-2015 13:34
Help! Dual V Belt alignment issue. darylat8750 Electrical: Batteries, Generators & Solar 17 02-03-2015 19:47
Converting Tiller Steering to Hydraulic Steering drewan08 Construction, Maintenance & Refit 6 31-03-2010 18:30
Don Allen Steering Wheel Issue - Need Help! rdcleveland Construction, Maintenance & Refit 3 23-01-2010 05:32

Advertise Here


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 09:21.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×

ShowCase vBulletin Plugins by Drive Thru Online, Inc.