Compact Hydraulic Steering Troubleshooting; Helm Becomes Jammed During Filling; Steering Hard To Turn; Helm Unit Bumpy - Requires Too Many Turns - Mercury BRAVO Service Manual

SERVICE MANUAL NUMBER 28
Compact Hydraulic Steering
Important Information
Whenever a troubleshooting solution calls for removal from vessel and/or dismantling of
steering system components, such work must be carried out by a qualified marine
mechanic. The following is offered as a guide only and neither Mercury MerCruiser nor the
helm manufacturer are responsible for any consequences resulting from incorrect repairs.
Most faults occur when the installation instructions are not followed and usually show up
immediately upon filling the system. The most common faults encountered and their likely
cause and solution are provided in the following.
Sometimes when returning the steering wheel from a locked position, a slight resistance
may be felt and a clicking noise may be heard. This should not be mistaken as a fault, as
it is a completely normal situation caused by the releasing of the lockspool in the system.
Avoid serious injury or death due to FIRE or EXPLOSION. Be sure that engine com-
partment is well ventilated and that no gasoline vapors are present to prevent the
possibility of a FIRE or EXPLOSION.

Helm Becomes Jammed During Filling

Blockage in the line between the helm(s)
and the cylinder(s).
System Difficult To Fill
Air in system.

Steering Hard To Turn

Steering cylinder pivot bushings are too
tight or trunion is bent, causing
mechanical binding.
Restrictions in hoses.
Air in hydraulic fluid.
Wrong hydraulic fluid has been used to fill
steering system.

Helm Unit Bumpy - Requires Too Many Turns

Dirt in inlet check of helm pump.
90-863160 MAY 2000
WARNING
Cause
Cause
Cause
Cause
Special Instructions
Make certain that hoses were not kinked
or pinched during installation. If so, the
hose must be removed and replaced.
Special Instructions
Review filling instructions.
Special Instructions
To test, disconnect clevis from steering
lever and turn the steering wheel. If it now
turns easy, correct cause of mechanical
binding. Please note that excessively
loose connections to steering cylinder or
steering lever can also cause mechanical
binding.
Find restrictions and correct.
See filling and purging instructions.
Drain system and fill with approved
hydraulic fluid.
Special Instructions
Replace helm unit.
TROUBLESHOOTING
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