Re: [OMC-Boats] Tilt Motor Issue

On Thu, 24 Feb 2011, Paul Hamilton wrote:
> I have been away from the list for time - it's good to see familiar names putting information
> out there.  In my time away, I've picked up 67 Rogue in very nice condition and a 67 Sportsman
> that's pretty good as well (I started with a 66 Sportsman).   The Sportsman has an issue with
> the tilt motor.  It always works going down and occasionally works going up.  It always works
> going up if I first turn the hand wheel a rotation or so.  The service manual describes a
> "hammer blow" coupling that allows 90 degrees of rotation by the tilt motor before engaging the
> worm gear which allows the motor to gain speed before it has to lift the motor.  Maybe the
> place to start?  
> I should probably start by quantifying just how much the hand wheel has to turn to make the
> unit operational, but it's heading below zero tonight so if the problem sounds familiar to
> anybody I would appreciate your help. 

When you turn the handwheel a rotation or two, are you turning it in the
direction that it would turn to raise the drive, or the opposite direction?
If pre-turning it in the opposite direction helps, I'd say it is almost
for sure the hammer-blow coupling. If pre-turning in the same direction
helps, it's harder to say, but it's also a good spot to suspect.

I would start by removing the cover from the tilt clutch housing,
inspecting the clutches (in-place, no need to remove them), and relubing
everything. You will probably need to replace the gasket when you do this
- they're a few bucks at boats.net or you can cut one out of gasket
material. Note that reassembling it without the gasket WILL NOT WORK - the
gasket is necessary to space out the cover, and without the gasket the
entire assembly will seize up.

After that, I'd check out the hammerblow. You access this by removing the
tilt motor from inside the boat. I hear this is very easy to do with the
L-4 engines, but on my V-6 it is very difficult to reach. You will
probably spend 30 minutes standing on your head working the bolts out. I
modified a nut driver to better fit mine. When you do get the bolts out,
carefully pull the tilt motor out. Note that the mounting bolts hold the
motor together, so it is possible for it to fall apart during removal (I
dropped the rotor out of a new motor into the bilge that way). Also be
careful about losing parts to the hammerblow coupling when you remove the
motor. One half tends to stick to the motor and the spring will stretch
and then pop loose and fling parts all around your bilge.

The coupling consists of two metal pieces with a spring between them. I'm
suspecting your spring has failed - the spring pushes the coupling into the
"unloaded" position, so the motor can rotate freely as it spins up. When
you hit the tilt button, the motor turns 90 degrees and then the two halves
of the connector engage and turns the worm gear shaft that drives the
tilt clutch. Without the spring, they'll just remain in their "last used"
position, so the motor faces full load at zero speed.

I believe a new spring only costs $5 or so (and it might've just gotten
disengaged and still be fine) - the entire coupling is over $50 (I thinking
it might be $45 per side). I think I ordered mine from Seaway Marine in
Seattle.

Ethan

-- 
<a href="http://homepages.cae.wisc.edu/~brodskye/"> Ethan Brodsky </a>