New Steering Issue - Sterndrive

[PSteward]

Hello!

Recently my steering decided to act up and when at speed I cannot turn right....
I have an OMC 7.4L 454 King Cobra sterndrive and generally haven't had any issues with steering except being a little "loose".
At low speed I have no issues turning either direction, when the boat is off and I push up the thruster I also don't have issues turning, but when I go above 11 KM/H it starts becoming harder and harder to turn right. As soon as I slow the boat it immediately frees up and allows me to turn right again.
No issues with left turns.
This is not related to Trim Tabs, they both have sensors and are working tip top, and besides at 12 KM/H they have no impact on the boat.

Any thoughts?!

Thanks!

[Sailmonkey]

I’m assuming you’ve got hydraulic steering? If so, is there sufficient oil in the system?

[GordMay]

Assuming you have ‘Power Steering’:
1998 OMC Sterndrive Manual
See Chapter 14 [begins page 593 of 615] ➥ https://sunbirdcorsair.files.wordpre...ndrive_man.pdf

[jimbunyard]

That's what I was about to say, check the level in the power steering reservoir. Though I guess power steering could also be called hydraulic steering, and vice versa...

[Boatyarddog]

Originally Posted by PSteward

Hello!

Recently my steering decided to act up and when at speed I cannot turn right....
I have an OMC 7.4L 454 King Cobra sterndrive and generally haven't had any issues with steering except being a little "loose".
At low speed I have no issues turning either direction, when the boat is off and I push up the thruster I also don't have issues turning, but when I go above 11 KM/H it starts becoming harder and harder to turn right. As soon as I slow the boat it immediately frees up and allows me to turn right again.
No issues with left turns.
This is not related to Trim Tabs, they both have sensors and are working tip top, and besides at 12 KM/H they have no impact on the boat.

Any thoughts?!

Thanks!

If you can plumb a pressure gauge into the assist pump and verify good pressure at all RPMs, the steering control valve is at fault.
If it isn't consistent, then the relief valve within the pump may be binding, flushing and refilling can help.
The link provided by Gord May explains the testing procedure step by step,14-4 figures 10,11
SV Cloud Duster

[Burr]

Originally Posted by jimbunyard

That's what I was about to say, check the level in the power steering reservoir. Though I guess power steering could also be called hydraulic steering, and vice versa...

It's most likely an hydraulic steering and needs lubrication.

[Burr]

Originally Posted by GordMay

Assuming you have ‘Power Steering’:
1998 OMC Sterndrive Manual
See Chapter 14 [begins page 593 of 615] ➥ https://sunbirdcorsair.files.wordpre...ndrive_man.pdf

This is very helpful. thanks GordMay

[jimbunyard]

Originally Posted by Burr

It's most likely an hydraulic steering and needs lubrication.

Typically on small powerboats, hydraulic steering consists of a steering wheel driven pump actuating a two way hydraulic ram attached to the steering arm.

On most gas sterndrives, the steering arm is actuated by a cable, which is assisted by an engine-driven hydraulic pump and actuator.

Low fluid in either can result in poor operation,

[Tin Tin]

If you have power steering, some things to consider:

Check the PS pump pulley belt is not loose.
Check the fluid level
Change the fluid - may not have been done for years, might have water in there.

There may be a power steering oil cooler, check this has no internal blockage or corrosion issues.
May have air bubbles in the system from leaking joints.
At idle turn full lock one way and then the other, check fluid level.

[Burr]

Originally Posted by jimbunyard

Typically on small powerboats, hydraulic steering consists of a steering wheel driven pump actuating a two way hydraulic ram attached to the steering arm.



On most gas sterndrives, the steering arm is actuated by a cable, which is assisted by an engine-driven hydraulic pump and actuator.



Low fluid in either can result in poor operation,

Thanks for the explanatory insight

[PSteward]

Hey guys,

You are spot on, it appears to be a fluid issue.
What fluid is recommended as a replacement to top up?

Thanks

[jimbunyard]

I just use the same stuff that you'd use in your car.

[PSteward]

I found it under the fluids section of the manual and put in Dexron III ATF.
Works Great!!