Steering line leaking

[paulga]

One hydraulic steering line inside the electrical box has been leaking slowly always. The copper line below a fitting appears oily in the outside surface. The flare fitting at the top of the photo also shows some oil at the tapered ends. What could have cause these fittings to leak slowly?

 

[Flatswing]

With flare fittings on River Girl, the cause was usually a poor flare-either too little flare or too thin and a small crack developed. Flares are easy to replace - if you can get access!

 

[paulga]

With flare fittings on River Girl, the cause was usually a poor flare-either too little flare or too thin and a small crack developed. Flares are easy to replace - if you can get access!

The fitting in the middle of the photo is not flare. Do you mean these fittings need to be replaced? Does it require to drain the entire hydraulic system, bleeding and refill?

 

[Flatswing]

Yes, agree re the middle fitting. Draining, refilling & bleeding - the worst part. I assume u have checked the middle fitting is snug?

 

[jleonard]

Id wipe the area clean then carefully put a wrench on each connection and snug it up just a little and monitor.

 

[C lectric]

I have many flare fittings and some of the compression fittings aboard. Doesn't matter. The odds are good that jleonard is right. Get a couple of wrenches and try snugging them up. Don't just grab only the ones for the big nuts, You need one wrench to hold the small hex and one to hold the larger hex. When tightening be sure the wrenches are fully engaged on the flats.

I have made many connections of this nature and it can be very easy to not tighten them quite enough. There may be nothing wrong with the connection but that.

Then wipe it down thoroughly especially the tube going down and monitor for a while.

 

[Flatswing]

Tightening the fittings can sometimes be tricky as the threads may bind under load. It’s the reason why some use a thin layer of PTFE tape on the threads of compression fittings and flare fittings - not as a sealing agent, but as a thread lubricant so they tighten more smoothly (and fully).

 

[paulga]

Tightening the fittings can sometimes be tricky as the threads may bind under load. It’s the reason why some use a thin layer of PTFE tape on the threads of compression fittings and flare fittings - not as a sealing agent, but as a thread lubricant so they tighten more smoothly (and fully).

I have heard flare fittings do not like teflon tapes or thread sealant. i thought it means these sealants actually disservice the sealing in a flare fitting

 

[paulga]

Id wipe the area clean then carefully put a wrench on each connection and snug it up just a little and monitor.

it could also be that someone over tightened the fitting using big wrenches, deformed the olive inside the fitting, causing the leak. in this case, is the only option to replace the fitting?

 

[sean9c]

I guess the theory on using teflon tape is that it's just on the threads and not on the flare or the sealing surfaces and it's just there to reduce the friction between the threads. I don't see that it's necessary and there is the possibility that you might get it on the sealing surfaces.
If it's a compression fitting (has an olive) it shouldn't be there in the first place, so cut it out and redo correctly.
If I was the OP I'd try tightening the fitting.

 

[Portage_Bay]

it could also be that someone over tightened the fitting using big wrenches, deformed the olive inside the fitting, causing the leak. in this case, is the only option to replace the fitting?

Not just the fitting. You may have to cut the line back past where the olive is, the copper may have been deformed in that area.

 

[jleonard]

it could also be that someone over tightened the fitting using big wrenches, deformed the olive inside the fitting, causing the leak. in this case, is the only option to replace the fitting?

Probably. But you wont know until you try to tighten and i mean just a little.
By the way, if the leak is only just enough to make the area wet ( as in no noticeable loss of fluid in the reservoir) it might be wise to let it be. Wrap a small piece of oil diaper around it and monitor.

 

[sean9c]

There have been a couple of mentions of an olive, which is also called a ferrule, these are used in compression fittings. The working pressure of compression fittings is lower than the possible pressure seen in a steering system so it's not advisable to use them.
For example, I have Kobelt helm pump and cylinder. They want you to have a system capable of taking 1000psi of hydraulic pressure. I don't know what other manufacturers spec but I've no reason to think that Kobelt is unique. In the pic it looks to be a brass fitting, a brass compression fitting that size is rated for about 200psi.

 

[SteveK]

@sean9c
I was my thinking it probably only weeps when there is no more travel of the piston..

 

[jleonard]

My Teleflex system was 500 psi and i believe the Hynautic was the same.

 

[sean9c]

@sean9c
I was my thinking it probably only weeps when there is no more travel of the piston..

There should be a pressure relief valve somewhere. Some are built into the helm pumps. They bleed pressure from one side to the other