Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-23-2018, 09:06 PM   #1
Guru
 
Lou_tribal's Avatar
 
City: Quebec
Vessel Name: Bleuvet
Vessel Model: Custom Built
Join Date: Jan 2016
Posts: 4,374
Hydraulic steering, what hose to use?

Last year I got my steering cylinder rebuilt as it was leaking. Seals were changed, rod was polished clean and everything was fine.
After a winter on the ground I noticed again some leakage. This time it is not the cylinder itself but the fitting connection. The leak is very tiny, but after 6 month on the ground it was clearly noticeable.
My setup is as follow:
From the helm the line is copper.
Between the cylinder and the copper line there is around 1 foot of hose, quite stiff but less than the copper line.
Fitting on this hose, both side is compression fitting with olive/ferule. And this is where the leak is.
I am not sure if the fitting on the cylinder is NPSM or compression.
To illustrate what I mean here is NPSM fitting:



And compression:

https://www.hydraulicsdirect.com/v/v...ompression.jpg

So the questions...
First: Is compression fitting common for hydraulic? Is it the right thing?
Second: Any advice on getting this leak free?
Last: any recommendation on hose to be used? I found a lot of different hoses that could fit.

L
Se
Lou_tribal is offline   Reply With Quote
Old 05-24-2018, 07:44 AM   #2
Senior Member
 
Sugardog's Avatar
 
City: Alexander
Join Date: Aug 2017
Posts: 152
Whe I was building boats where failure was not an option, it was Aeroquip hose and fittings.
Sugardog is offline   Reply With Quote
Old 05-24-2018, 07:54 AM   #3
Veteran Member
 
Cold-smoked's Avatar
 
City: Tromso
Join Date: Feb 2018
Posts: 83
I have the same setup, but found that all fittings were leaking due to missing inserts in the copper pipes.
Cold-smoked is offline   Reply With Quote
Old 05-25-2018, 12:31 AM   #4
Guru
 
C lectric's Avatar
 
City: Gibsons, B.C., Canada
Vessel Name: Island Pride
Vessel Model: Palmer 32'
Join Date: Oct 2007
Posts: 4,409
Try loosening, two wrenches, the ferrule nut and then wiggling it as you resnug it up. THis hopefully will align it better. Once snugged then use two wrenches to tighten the nut fully.
The two wrenches are often needed to turn only the nut. If the whole thing twists you may monkey the fitting and tube so it can't be fixed.
Generally compression fittings are not a good bet for use in an application like this. Although a low pressure hydraulic system they can still see up to 1,000 psi. Compression is usually used on much lower pressure.

You do not need the two types of fittings you showed. They are high pressure fittings, expensive and not common.

If the copper tubing is in good shape then consider purchasing a DOUBLE flaring tool and learn to use it. It's not hard. A few practice flares with some extra tubing will do it. That will produce a good seal. Just be sure to put the nut on first before forming the flare.

Then other fittings can be adapted easily.
YOu might be able to adapt the hose end to the new flare with the right fitting.
Without seeing this it's kind of hard to say how to do the repair.
My own system is copper tubing, flare fittings using a double flare tool and it has been leak free for 40 yrs with a few exceptions and those were single flairs that were poorly done and cracked.

For new hose talk to your local hydraulic shop. A working pressure of up to 1,000psi should be more than enough. THere is very little movement of the hose so a hydraulic hose like this will still be flexible enough.

Some photos of what you have?
C lectric is offline   Reply With Quote
Old 05-25-2018, 06:27 AM   #5
Technical Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 6,194
Lou, I have been around a lot of hydraulic fittings, and I don't recall ever seeing the type that you posted. If they are used only at the rudder cylinder, consider going to a hydraulic shop and getting new fittings that are industry standard. They can make up the hoses for you too. Aeroquip is fine, but so would anything that meets spec for 1000psi oil.
Ski in NC is offline   Reply With Quote
Old 05-25-2018, 06:35 AM   #6
Guru
 
Lou_tribal's Avatar
 
City: Quebec
Vessel Name: Bleuvet
Vessel Model: Custom Built
Join Date: Jan 2016
Posts: 4,374
Thank you guys, I think I will pass by the shop that changed my cylinder seals last year to ask them to provide me with two hoses.

L
Lou_tribal is offline   Reply With Quote
Old 05-25-2018, 08:22 PM   #7
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 18,738
I used hose normally used for front-end loaders. It’s orange, and much bigger than the shiny and small black hose usually used.

Used a oversized steering pump and slave cylinder too. Was looking for stuff that wouldn’t fail in Alaska.

Everything worked well and I’m set up for 3 turns L to L. Due to the fast steering, large shafts and seals and other oversized components I do have a little more steer effort required than for most boats this size.
__________________
Eric

North Western Washington State USA
Nomad Willy is offline   Reply With Quote
Old 05-27-2018, 08:27 AM   #8
Guru
 
City: Seaford Va on Poquoson River, VA
Vessel Name: Old Glory
Vessel Model: 1970 Egg Harbor 37 extended salon model
Join Date: Jan 2016
Posts: 2,264
I dont like olive ferrule compression tubing fittings much at all, they want to leak, low pressure water systems seem ok sort of with them. It is how they built my boat back in 1970 using all annealed copper tubing, which I have maintained, mainly cause copper kills bacterias, and what I have works.

Flared made for hydraulic type fittings are what you want.
sdowney717 is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 04:25 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012