Hydraulic steering line failure

Four Suns

Four Suns

Not a pot stirrer
TECHNICAL Contributor
Oct 4, 2006
10,533
Williamsburg, VA
Boat Info
2003 480 DB
Engines
QSM-11 Diesels
I went out for a little evening run tonight. About 10 miles from the dock, the steering wheel doesn't do anything... I'm thinking the autopilot must be engaged. NOPE! I went down in the engine room and red hydraulic fluid is everywhere... Great... I limped back to the dock with no steering. If you have never had the pleasure of running a 50 foot boat with no rudder control, you should try it. I felt like that pilot that crash landed the DC-10 in Iowa by using just the engines to turn the thing... oh... and I really used the bow thruster tonight as well.

I took these pictures when I got back. Here's the fluid under the starboard engine I discovered:

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And here's the hose connected to the transmission oil cooler:

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And here's the hose taken off the cooler. Note the reservoir tank in the background that is EMPTY. Also notice the very well manicured fingernails...

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I think this hose just exploded:

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I noticed these weak fittings on this engine/steering system a few weeks ago but thought they would hold up a little longer. Guess I was wrong. Geez... I should never be a pilot or flight mechanic. The fittings for the hydraulic steering are just barbed fittings and frankly I think the engine vibration killed them...

Love that bow thruster.
 
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Gary, that's a good item to share! I was operating my brother-in-law's tractor with a farm hand (hay grapple) on it a couple of years ago. Had it about 8 feet in the air, extended horizontally, when the hydraulic line that held it horizontal broke. It crashed to the ground before I knew what was happening. Turned out that part of the line was metal tubing, and it had rubbed against the front end loader frame long enough to wear through. Then this past summer another of his hydraulic lines broke from wear.

It taught me that I had become, or always was, overly complacent about hydraulic lines. I've painted my 38 by 48 by 14 high shop working out of the bucket of my tractor. I now know that was not very smart. You depend on these lines for your life in some situations; they deserve more attention than they typically get. Maybe someone else can comment on how to properly inspect them, I don't feel qualified to do that.

You were lucky your failed when you could get along without steering. I am sure you can imagine much worse times. Chalk it up to experience. The great thing about the board like this is that we can all learn from it when you take the time to post what happened. Great pictures, by the way.
 
I'm just hoping I didn't hurt the pump getting home. It's not like you can just turn it off when it is directly hooked to the tranny.

Like I said, I saw the issue with the hoses a few weeks ago but decided to keep using the boat. That was stupid. Have to stop listening to Frank W. ;-)
 
That looks like a pretty big pop. That must be some serious presure in there. Good thing you weren't in the ER when it went. by the way, your nails look great.
 
Wow... looks like fun!

And now I will demonstrate my overwhelming grasp of the obvious: Seems like the type of thing that should have braided SS hoses.

What's the replacement/repair plan?
 
ImpulseIII said:
Where was your duct tape?
Click to expand...

I think that one was beyond a tape fix. There was only a little rubber left even holding the hose together. All those blue hoses on the cooler appear to be dry rotting at the fitting for some reason. The fittings for the steering system are different, which is what I was asking you about Matt, than the other fittings which have a metal jacket around the end. In fact, the hydraulic steering has a mix where some hose fittings are this push on type and some are the better quality ones with the jacket. What the heck? Anyway, I'm off now to go get some new ones made and am just replacing all the blue hoses on the system with better quality hose and fittings.

BTW.. when I was coming back to the dock, some jackass in about a 20' SEA RAY (red bottom) had mounted freekin' half a dozen OFF ROAD bar lights on his wakeboard tower facing forward and was coming down the channel by my house at about 40 mph with the lights all lit up. It's pitch black out and the thing just blinds me and he goes flying by me about 10 feet from my port side. IDIOT!!!! People that think boats should have headlights should be removed from the water as they are just STUPID. I hope he reads this forum. "YOU ARE STUPID!!! YOU SHOULD NOT OWN A BOAT."
 
I really find it surprising the hoses should fail at all. A high pressure hydraulic hose is not something you expect to go bad unless it gets cut or is undergoing constant flexing or is being rubbed against something. Normal vibration shouldn't affect it. Who makes the steering system hydraulics? I think a call to them is in order for some serious complaining.:smt021
 
Yeah.. I'm not sure but something may not have been installed right... I'm checking it out now.
 
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Dave S said:
I really find it surprising the hoses should fail at all. A high pressure hydraulic hose is not something you expect to go bad unless it gets cut or is undergoing constant flexing or is being rubbed against something. Normal vibration shouldn't affect it. Who makes the steering system hydraulics? I think a call to them is in order for some serious complaining.:smt021
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I mentioned two hydraulic hose failures above, and a neighbor just told me he got sprayed good in the face and all down his front when he got a hydraulic leak on his old tractor. This happened a couple of months ago. Also, 10 year ago, I was involved in trying to get some equipment installed in a mountain top comm site before real winter set in. We had two snow cats to take stuff into the site. On the first day, half way to the site, one of the show cats blew a hydraulic hose and lost its drive power. I considered that a bad start and cancelled the job till spring.

These things happen, whether they should or not. I think in a boat a hydraulic hose that is not completely restrained will always be subject to movement. Also, when you put pressure in the hose and later release it, the hose will try and move anywhere there is a bend in it. It will try and straighten out under pressure.

I'm not trying to say that the hose was not poorly made, or wrong for the application. I am just saying that when you take the boat out, you are the captain, and you are responsible at that point to be sure it is sea worthy. You own the monkey!
 
I suspect heat is the culprit here. These hoses are usually fairly long lived in the auto environment. I would think they would last much longer on a 5 year old boat. Given their proximity to the heat changer maybe there should be some kind shielding.
 
So.. here is what I found out.

The hoses/fittings that are failing are on the low pressure side of the power circuit of the hydraulic system. The hoses are Aeroquip FC332-08 hoses with a 1/2" inner diameter and have a 250 PSI rating stamped on the side them. This rating is less than what the installation guide calls for that came with the system. Additionally, the fittings are a push-in barb fitting and are not crimped on like you typically see on the boat. Heck... even the Cummins fuel and oil lines that are low pressure have high quality crimped on fittings. Here are some shots of the old hoses that were replaced today:

hose2.jpg


That is really bad workmanship on the fitting install. Here is a shot showing how the hoses are just cracking:

hose1.jpg


I post this stuff not to bash Sea Ray or anyone. This is a serious issue. Blowing a hydraulic line is not something you can easily fix when you are offshore and you are helpless when it happens. If you have these hoses, you need to WATCH them. They are not good.

I did have all these hoses replaced with Parker hoses that have crimped on fittings and exceed the installation guidelines. They are sweet... I'm going out for the weekend so we'll see if I have anymore leaks.
 
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Gary - I am a certified hydraulic guy...it is hard to determine from your center photo if abrasion or heat caused the cover to expose the braid. Depending on the manufacture of the hose, a push on style hose end will be rated for around 250 psi with a 3 or 4:1 safety factor...was there any information on the layline of the hose that mentioned working pressure? Depending on the hose length, there may not have been.

I primarily work with Parker Hydraulic products. Their Marine Steering hose MSH has a 1000 psi constant working pressure in 5/16 and 3/8 id. There are two methods for attaching the ends for the MSH series hose. There is a crimped on or they offer a field reusable end. The field reusable would allow you to make a repair with common tools you carry on board and still have the 1000 psi rating. The hose ends usually have a 45 degree female swivel end, noted by the hash mark(s) on the wrench flats.

Power steering pumps are generally a vane type. Since you were running low rpm, you are less likely to cause harm to the pump....how long was the trip back to the dock?

BTW - nice job on bringing the boat in, I remember that firey day in Iowa...and to think he almost pulled it off...damn
 
Jeff,

Thanks for the response. I don't know poop about all the hydraulic stuff other than my 7 years of engineering degrees... I know how it works and that's about it.

Stray Cat said:
it is hard to determine from your center photo if abrasion or heat caused the cover to expose the braid. Depending on the manufacture of the hose, a push on style hose end will be rated for around 250 psi with a 3 or 4:1 safety factor...was there any information on the layline of the hose that mentioned working pressure? Depending on the hose length, there may not have been.
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The hose in question has 250 psi stamped on the side. It is Aeroquip FC332-08 with a 1/2" inner diameter.

http://www.hosexpress.com/hose/socketless/FC332.htm

I verified with Teleflex/Seastar that this hose does not meet their install guidelines today. Frankly, I think the failure, beyond the fact the PSI rating is too low, is because the poor installs but the heat was starting to do a number anyway.

Stray Cat said:
I primarily work with Parker Hydraulic products. Their Marine Steering hose MSH has a 1000 psi constant working pressure in 5/16 and 3/8 id. There are two methods for attaching the ends for the MSH series hose. There is a crimped on or they offer a field reusable end. The field reusable would allow you to make a repair with common tools you carry on board and still have the 1000 psi rating. The hose ends usually have a 45 degree female swivel end, noted by the hash mark(s) on the wrench flats.
Click to expand...

I had a shop just make up replacement parker hoses that have a 1/2" ID and put the crimped fittings on. They are great looking hoses. Much better than the other ones.

Stray Cat said:
Power steering pumps are generally a vane type. Since you were running low rpm, you are less likely to cause harm to the pump....how long was the trip back to the dock?
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Took an hour to get back. The system was filled back up today and bled and it seems to be working just fine. I'm going out and run it tomorrow and exercise the system so we shall see.

Stray Cat said:
BTW - nice job on bringing the boat in, I remember that firey day in Iowa...and to think he almost pulled it off...damn
Click to expand...

I'll never forget that day... I have an aeronautical engineering degree so I'm aware of the physics but can't comprehend what it must have been like in the cockpit.
 
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Probably not a good day to go out see if the steering repair is working correctly..

SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 6 PM EDT THIS
AFTERNOON

REST OF TODAY
N WINDS 20 TO 25 KT...BECOMING NE 15 TO 20 EARLY
IN THE AFTERNOON. WAVES 4 TO 5 FT.
 
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