CONTINUOUSWAVE

My 2000 Alert 17 (special service classic Montauk), has the BAYSTAR model hydraulic steering. A few years ago I refreshed the [hydraulic fluid] and bleed (air from the system].

In the 2025 season the BAYSTAR steering has begun a behavior that is described in the troubleshooting section of the documentation: it takes way too many turns to go lock to lock. Only it’s butter smooth. Not stuttering like you might get with air bubbles and a bad bleed. The documentation says that this is probably due to fouling of the internal valving in the helm.

Q1: do readers agree that the cause of having too many turns lock-to-lock is due to fouled internal valves in the helm?

Q2: or, do readers believe the cause of having too many turns lock-to-lock is due to [air in the system, as a result of a] bad fill and bleed?

-Peter

I believe that the steering helm is actually a bi-drectional pump. If the steering wheel is turned, say, clockwise, then the pump pushes hydraulic fluid out of the pump and into the hose that will cause the outboard engine to be pushed to port, causing a turn to starboard. The output of the pump does not flow into the other hose because there a valve arrangement in the helm, probably some sort of check valve.

When fluid is pumped to the actuator at the engine, it moves the steering actuator, which displaces fluid that flows back to the helm pump, where the valve arrangement permits the returning fluid to flow into the sump or reservoir of the pump so there is always more fluid available to be pumped out.

When the direction of rotation is reversed, the pump pushes fluid out the second hose, and the engine turns the opposite way, and fluid returns on the first hose.

If the steering wheel can be rotated without much apparent effort and the engine is not moving, then there are two possible causes:

• the pump is not creating any pressure to move the fluid, so the fault is in the pump; or
• the actuator is not creating any resistance to movement, and the fluid just flows through the actuator and back to the to pump without producing any engine movement.

Because the company that designed and manufactured the steering pump knows a lot more about the design and behavior of the pump than I do, I would suspect that the cause of the problem described is, as the company mentions in their literature, in the pump itself.

If the engine eventually turns but in jerks and stops, the problem could be air in the system.

I don't know the remedy for a steering pump with problems with its internal valves.

Opening a bleed valve and adding more fluid and turning the wheel back and forth is usually the method to bleed air from the system. But can be sloppy to perform and can waste a lot of expensive fluid while performing the bleed.

Dealers often have an accessory device that is called a hydraulic steering system Power-Bleeder. This device is connected to the system by two hoses, as I recall, and will quickly remove all the air. On my rather old hydraulic steering system, my dealer used a his Power-Bleeder to expel air about ten years ago. Following that event the steering had absolutely no slop or dead-zone when changing directions, and has maintained that state ever since. Also power bleed seems to minimize any loss in fluid.

So, more data….

I got back to the house where we keep the boat, and was able to do some more sleuthing.

-If I turn the steering wheel slowly like you might do making small corrections to line up with the trailer there is almost no engine movement at all no matter how many times you turn the wheel

-If I turn the wheel as fast as I can, it is able to build pressure and the lock-to-lock is about as Dometic says it should be, about 5.5 ish.

-once you turn the engine to a stop, you can keep turning the wheel indefinitely with a little extra effort, but not much. At no point does the wheel hard lock against the stop.

-Also (again), the wheel is absolutely smooth, which suggests to me, no air bubbles.

-Peter

Before spending a lot of money time on your problem I would go to the nearest airport and purchase a gallon of the proper milspec hydraulic fluid for your system. I would then flush the system a time or two and test. If flushing fails to revive the system after a few tries I would overhaul or replace the helm pump.

Jefecinco wrote:Before spending a lot of money time on your problem I would go to the nearest airport and purchase a gallon of the proper milspec hydraulic fluid for your system. I would then flush the system a time or two and test. If flushing fails to revive the system after a few tries I would overhaul or replace the helm pump.

One step ahead of you in that one, mate ;) Big fan of 5606.

You might or might not know that I’m an airline pilot and can get all the Skydrol I want…. Except Skydrol is NOT 5606. Booo.

Sadly for me, since filling and bleeding is a two-man job, and my wrenching partner is my 14 yo daughter it’s going to have to wait until a school break and I can get her out to the lake house where the boat is.

-Peter

Ok so I bled it right. Well, I didn't use Dometic's exact procedure that requires two people. Based off of a YouTube video I found, I did effectively more or less the same thing though. I Tee'd the two bleeders into a single line running back up to the inverted bottle keeping the helm full, such that turning the helm pump in either direction would pump fluid to the cylinder, back out the cylinder, up the line I ran, back into the fill bottle, so the fill bottle never ran out. With both bleeders open at the same time, turn the wheel many turns in one direction until you see no air, then turn the wheel many turns in the other direction until you see no air, the clean up and you are done. Found and purged a segment of air about a foot long. No more air after dozens of turns in either direction. Big improvement now. Will probably stick with this ancient (25 years old) helm a little longer.

I am a little bit surprised that a one-foot length of air would cause the problems I described: little or no engine movement when turning slowly, and normal engine movement when turning rapidly.

-Peter