350 Mag Bravo 3 with poor power steering assist

[iammarcuse]

A couple of year old thread but hoping for some responses. I have the exact same problem. Steering is stiff at the start of a turn. Unhooked all the clevis pins, outdrive moved easy and steering wheel moved easy. Steering cable was not binding in tube. Taking the advise of this thread I replaced the cable, which seemed perfect BTW. I assumed things would be fine once I got the boat back in the water. No love. Still sticking a bit when you go to turn. When I did have it all apart I tried to move the actuator valve by hand (like in the video posted in this thread.). It moved, but needed a good push or pull and then the power assist kicked in. How easy should that thing move by hand? It would seem now that maybe that spool valve shaft is binding slightly? idk Thinking of pulling the valve shaft out, but then what? Any thoughts?

 

[Bondo]

A couple of year old thread but hoping for some responses. I have the exact same problem. Steering is stiff at the start of a turn. Unhooked all the clevis pins, outdrive moved easy and steering wheel moved easy. Steering cable was not binding in tube. Taking the advise of this thread I replaced the cable, which seemed perfect BTW. I assumed things would be fine once I got the boat back in the water. No love. Still sticking a bit when you go to turn. When I did have it all apart I tried to move the actuator valve by hand (like in the video posted in this thread.). It moved, but needed a good push or pull and then the power assist kicked in. How easy should that thing move by hand? It would seem now that maybe that spool valve shaft is binding slightly? idk Thinking of pulling the valve shaft out, but then what? Any thoughts?

Ayuh,...... So, when you changed the cable,....
What condition, 'n which helm are you dealing with,..??

 

[iammarcuse]

It is a Teleflex Seastar HPS model SH91650P (it is not "no feeedback") tilting helm. There is only 185 hours on the boat. Never in salt water. No corrosion anywhere. The helm has a small amount of play before it engages the cable. Maybe a 1/16th of a turn. The old steering cable was in perfect condition and moved easily. But I changed it anyway as maybe it was worn and had slop.
The drive is a bravo one and moves by hand from side to side with no binding if i disconnect the clevis pin. The steering cable moves effortlessly as well when disconnected from the power steering actuator.

While running on the water, if I move the steering wheel quickly there is a smooth quick response from power steering. If i move it slowly (which one does more commonly) it is sticky and does not engage the power steering as well. If I move it very slowly I get no power assist. Thanks for your response.

 

[alldodge]

Sounds like it's in the PS ram
Are the flats up and down as in figure d ?

 

[Bt Doctur]

That unit can be dis-assembled and cleaned internally

 

[iammarcuse]

Yes, flats are up down. thx.

 

[iammarcuse]

I know how to open it up and have seen pics. What would cleaning it look like? If I could do it without pulling the actuator that would be WAY easier. I could take the valve shaft out without pulling the whole unit out. It is one of those applications where the engine compartment buries everything at rear. Even changing steering cable was a royal pain.

 

[iammarcuse]

 

[iammarcuse]

Found this pic on another thread.

 

[iammarcuse]

My sense is the valve shaft does not move as easily inside the housing as it should. Hence when turning steering wheel slowing, it doesn't move at all and engage the power assist.

 

[alldodge]

The inner cable when applying pressure "should" move the valve rod ever so slightly. If turned quickly it will move the rod a bit more. When cable stops applying pressure to the valve rod it will self center and thereby stopping the assist

I sounds like the valve rod is partly stuck. This is why it works fine when turning fast and not so much with only slight movement

 

[iammarcuse]

Thanks for the great diagram. You could be correct about it being only partially stuck. Any idea what I would look for when I open it up that might be the problem?