how to adjust ST4000 (grey) autopilot

[dhagen]

I have the gray Raymarine ST4000 autopilot.  My belt is too tight and won't let me turn the wheel smoothly when the autopilot is not engaged.  I know there is a small plastic plug on the back side that allows me to access a small allen screw with a small hole to the right and left to adjust a small silver wheel.  However,  I cannot get the allen screw to turn and don't know if I get it to turn, whether I need some sort of wrench to fit the 2 holes to make the adjustment.  Any ideas?

[Dave Spencer]

There's an ST4000 repair manual on the tech wiki that has good information including and exploded view of the wheel mounted unit on Page 12.  It should be helpful.
Here:
http://c34.org/wikiwp/?rdp_we_resource=http%3A%2F%2Fc34.org%2Fwiki%2Findex.php%3Ftitle%3DManuals

Scroll down to "Misc".

[dhagen]

Thanks. I have the manual, but it doesn't say how to make the adjustment.  I don't know if the allen screw is just stuck or if there is more to it.

[sailaway]

Had the same problem had to put new rollers in the big wheel . does it make a noise when you turn it. Charlie

[Dave Spencer]

Raymarine has a fairly decent technical forum.  You may find the answer to your question there.  Or, you can login (join the forum) and ask a question.  I've found it's hit and miss but if you get a hit, there can be useful technical support from knowledgable Raymarine people available, even on long obsolete items. 
http://www.raymarine.com/knowledgebase/index.cfm