Hydraulic steering

Our new to us 38' Present has dual hydraulic steering. No documentation came with the boat. There is an apparent hydraulic leak at the steering cylinder in the back. What is involved in topping up the hydraulic fluid? There is a plug at the top of the upper steering pump. Can you just add fluid at that point or is there some purging routine required?

Thanks,

Bob

MY Compromise (it's a boat, but not a sail boat)

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Greetings,
Mr. BobH. If there is a "plug" at the top of the upper pump I would guess this is where you would add the fluid. I've been told that it is IMPORTANT to add the appropriate type of fluid. Some systems use ATF (automatic transmission fluid) while others take a specific hydraulic fluid. If your units have a makers name or mark you may be able to search their website to ascertain the recommended fluid. Mixing the wrong types could do some damage.
That being said, unless you can see what the current level is, it will be difficult to top up the pump without getting fluid all over the place. If there isn't a dipstick attached to the plug, remove the plug and insert a small dowel of wood to determine the existing level. Get a pump type oil can and fill with fluid.

http://www.amazon.com/Metal-Oil-Can-Flex-Spout-Thumb/dp/B00383OREQ

For example...

** Squirt enough fluid to almost fill the pump and leave the plug out.* Check and note the fluid level.* Go to the lower station and crank the steering wheel fully left and right.* Do this numerous times (maybe 12-15).* Have someone standing by at the filler plug in case fluid flows out during this procedure.* Check fluid level again.* If the level has remained the same, you can be fairly confident that no air is in the lower pump.* Repeat turning regime for the upper wheel checking the fluid level after every 3-4 rep's and adding just enough fluid to keep the level just below overflowing.* During the first few rotations, keep a sharp eye out for fluid overflow (any entrapped air may cause overflow).** Keep repeating this turing process until level in pump remains constant.** You should be good to go.


-- Edited by RT Firefly on Tuesday 27th of March 2012 10:02:03 AM

BobH, If it is Hynautic steering, look in the eingine room and see if you have a reservoir for the system. It will be a long cylinder looking thing with 2 lines coming out of the bottom and a pressure gauge on top. You remove the plug here, fill the res., put in 10 PSI of air. Then start at the furthest steering station (usually the fly bridge) and turn the wheel as RT says. Then go to the next station and do the same. You keep doing this until both stations no longer feel mushy. Make sure the air pressure is at 10 PSI and the cylinder is above the full mark. I recommend that you use only Hynautic Fluid in the system. Then find and fix your leak, you may find that just using the system will lube the O'rings and fix the problem for you. Good luck! *

Jim

I agree with all that has been said. With that said, when you add fluid, make sure you burp any air that may have entered the lines. As you move the wheel to the right and left as mentioned, have the person watching the fluid note if air is coming out, thereby lowing the fluid level. Add fluid and as needed to make sure the level is full and no more air (if you had any in the lines) is coming out.

I also agree that you should use the same fluid that is currently in the system. Mixing fluid can cause damage. If you know the brand / model of your system, the manuf may have PDF manuals on-line or someone in tech support might be able to give you addtional instruction for your system.

I wrote to a vender about a old inverter model that presented very strange behavior. As it turned out, the fix was not something I would have thought of and was as obscure as the systems. I followed his instructions and like magic, the system functioned correctly.

I has to add a lot of fluid to my system last summer after removing an old *and installing a new autopilot pump on the boat. This had to be tied into the steering system. In my case, as you would expect, there was a lot of air to purge. Also I wish I had the oil can, with a small funnel and hose, it was still a mess.

Good luck.

When we took the boat out for the sea triel it steered fine. But since there seems to be a leak I am trying to be prepared. Next time on the boat I'll see if I can find a manufacturer's ID.

We once owned a boat with Mercruiser I/O drive and hydraulic steering. Don't remember the brand but they offered a special plug to which you could attach an upside down bottle of hydraulic fluid. Then you would exercise the steering and watch for bubbles in the can plus it would keep up the level of fluid.

Bob

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Bob, Here is some info that might help if you find you don't have a reservoir. http://trawler-beach-house.blogspot.com/2009/09/steering-issues-and-preparing-for.html . Chuck

Thanks, that was helpful. I found a copy of a previous survey and it listed the steering as a Capilano. That turns out to be a Teleflex brand. I just need to check now which model it is. From what I remember looking at it last time it's one of the 12XX models which use ATF fluid.

Thanks,

Bob

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With the Capilano it's usually the O-ring needs replacement. Try the new "square" O-rings.

You are talking about O-rings in the cylinder?

Bob

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