----- Original Message -----
Sent: 06 Apr 2012 12:02:00 -0500
motormodel: GM 454 MAG
boatmodel: 2000 Baja
Boatlocation: Mabank, TX Fresh Water
TechQuestion: Submit Question
06 Apr 2012
Replaced Power Steering Pump
Replaced Power steering Actuator
Replace Power steering high pressure hose
Filled with Dextron II fluid
I have a 2000 Baja with a 454 Mag MPI. Since I bought it used in 2006, the
power steering seemed stiff in operation. This year I decided to fix the
problem so I purchased a new power steering pump. The pump is a Sierra and
supposed to be the exact replacement for the Mercury 16792A39. After
installing this pump, there was no change in operation. I figured it must be
the actuator, so I bought and installed a new actuator and replaced the high pressure
line. Still no difference in the steering from motor off to on. I took the
boat out to see if it was drivable and when I powered up, the steering locked
up. I had to idle back to the dock. I have followed all the procedures in the
service manual for bleeding air out of the system and at this point I am
stumped. I checked the cable when I had the actuator out and it moves freely
with little effort. Any ideas what could be the underlying issue here?
Sounds like the problem has gotten worse instead of better... even though you
have replaced the two major components.
Since you say that the steering locks up now, when powered up from idle, there
are a few things left to look at.
A: Check that the stern drive pivot is not binding. Remove the pin from the
tiller arm of the stern drive and make sure it pivots freely without the
steering actuator attached.
Also, make sure the steering cable moves in and out freely as well, while
disconnected from the actuator. And, that the steering cable can move freely at
the actuator where the cable goes into the actuator. A tight bend before the
actuator and/or wire ties and/or steering cable contact with an obstacle can
send a false reading to the actuator.
B: Check for kinks in the return oil line between the actuator and power
steering pump. Remove any wire ties that may be supporting the hose and/or used
to tie something to the hose. Since it is low pressure/high volume, any
restriction can cause back-pressure which hinders operation.
C: Then drain the steering system and check the low pressure hose and oil cooler
for flow. Disconnect the low pressure hose from both ends and use low pressure
air to blow through. If it doesn't purge easily... there is a blockage in the
low pressure side of the system. Be sure to catch the oil at the other end...
Hope this helps. Let me know if you need more.