Power steering leak

planesailing

i seam to be loosing power steering fluid as I'm having to fill the tank every couple of weeks but can't see any signs of a leak. Anybody got any idea where I could be loosing fluid? I have a 242 with merc 5.7 efi bravo 3.

Handymans342

Has to be somewhere because everything is located in the engine bay. 

rasbury

your not pumping it out with other bilge water? Like Handy said, it has to be going somewhere, it does not burn up or anything...I have a slight leak somewhere as well, never see anything in the bilge but it is a minor leak and assume it goes out with the wash water as they say...

planesailing

I've looked at all the pipes and the pump but all looks ok. No sign of fluid in the bildge unless it gets pumped out. It's a mystery!

MarkB

If it gets pumped out, you would see it at your marina. A little bit of hydraulic fluid will cause a big (very big) slick.  It likely won't all come out while you're cruising. What does your bildge water look like?

212rowboat

Why wouldn't it mark?  If it's leaking under pressure, it would only while being used... 

Handymans342

How much fluid are you adding?

floater212

my first thought, since you don't see anything, how about the steering cooler? it's all enclosed so the fluid would go out with the water from the engine and exhaust. just a thought.

Handymans342

Good catch

MarkB

212rowboat said:

Why wouldn't it mark?  If it's leaking under pressure, it would only while being used... 

Because it's leaking into the bilge and will float in the reservoir. It will not completely drain all of the time to the point that there is no evidence of it when the bilge drains at the dock. At some stage the bilge will kick on at the dock, and bingo you'll see the slick. It takes only a fee drops of hydraulic fluid to make a very obvious slick coming from the boat.

Michael T

Any of the engine fluids that reach the bilge can leave a very obvious "slick" on the water. A bad idea in Canada a potentially disasterous event in the U.S.A. - prosecution wise.

zaverin1

I had a low pressure aka return line go bad.
small pin hole behind the engine. It rubbed thru over the years. There is a metal clip holding the hose in place on the engine side.
i had to bend the clip and when i did that it started spraying like crazy.
long story short I had a leak but went thru heII trying to figure out where it was coming from. I was getting fluid in my bilge.
my guess it's either being pumped out or it's a such a small leak that it's collecting on the back side of the engine.
it also could be the cooler. 
Cooler hoses swell up and leak or cooler itself is failing.
deoending if it's a single or a twin it's not bad a of job either way to change them.
2 small hoses
2 large hoses and clamp to undo.

planesailing

Thanks for all the info guys. Quick update for you... Was at the boat today and checked the fluid level and as expected was low. Put about 3/4 litre of power steering fluid in and took boat out for a good half hour. Moored up at local dock and checked level and it was still showing full. Left boat sitting for about half hour while we had lunch then drove it back to my home marina (15 mins away) and rechecked fluid whilst docked and the dipstick was dry. No sign of fluid in the bildge either! This has really stumped me!!! Any ideas??? only appears to loose fluid once it's been run and then left to sit for a bit! It's a strange one!

Handymans342

Has to be the cooler

planesailing

Are there any tests I can do on the cooler to make sure it is that before replacing it?

Handymans342

Should be able to do a pressure test. 

planesailing

Quick update for you.... After hours of searching for the mysterious leak I managed to find it yesterday! Turns out there is a very small crack on the underside of the power steering pump that only leaks once the engine has been running and become warm, I'm guessing this causes the pump to expand and the crack to open slightly alowing the fluid to leak out, as soon as the engine cools down the crack must contract enough not to allow any fluid to leak out! This explains why I couldn't see any signs of a leak when the boat was in the dock!!! New pump on order so should be back to normal soon! 

MarkB

Well done! There's a good reason for everything. Except politicians ... no good reason for them. LOL.