MCI power steering box adjustment?

[Garymci5]

I managed to yak a lot today, but my original intention was to find out the best method to adjust the power steering box on a MCI 5a. 

There appears to be numerous jam nuts on the unit.  The service manual isn't being much of a help on this one.

I can post a picture if needed, but anyone that knows the setup probably doesn't need it?

Thanks!

[buswarrior]

yes, and IIRC, you need to be careful, carelessly too tight and you can break it simply by turning the wheel the first time under power?

Adjusted wrong, and you'll row down the highway, every twitch to the left, needing a correction to the right, needing a correction to the left, as the hydraulics start squirting back and forth in a feedback loop, instead of having a centre.

I wish I had paid more attention when the opportunity was there to see it being done by a guy who knew how...

someone else with better details will chime in shortly.

happy coaching!
buswarrior

[Garymci5]

Those are words to the wise, as they say.

The steering isn't bad, by any means, I just want it tighter-- providing the steering gear isn't worn too  much on-center. It feels consistent, and the PS fluid is clean, with only a very minor leak at the front.  Hopefully a sign the gears and bushings are in good shape and can be correctly adjusted up a bit more.  Otherwise she goes down the road very nicely.

I probably need to stick my nose in the service manual again and have another look.

I'm an ASE Certified Master Auto Tech, so at least the paper says I know something; 14 years and 3 buses helps a bit too 

[bevans6]

My MC-5C manual has a complete section on adjusting the Ross steering box.  There are a lot of steps.  Basically you adjust a preload on the lever arm until a little drag is felt at the high spot (usually the center) then back off to zero play.  But any instructions are useless without the diagram, and only marginally better with it...  the adjusters seem to be on side cover in line with the end of the lever shaft (which is the bit that the pitman arm attaches to, only the opposite side) inside of the 1 1/4" lock nut.  You loosen the lock nut, screw the adjuster in a bit till it just drags in the center, back out 1/16th turn, see if it drags, etc, tighten the lock nut and see if it worked.  the idea is you are pushing the pins on the lever further into the grooves on the cam.  the cam is ground shallow in the center so you can adjust for zero slack in the center and still have looser steering at the extremes.  so make sure you are at the  center when adjusting, and make sure to check for tightness all the way.  It would be bad to adjust for zero play in the center to have it bind at full lock.

There are also instructions on bearing preload, centering the box, adjusting the drag link, and so on.

edit also this:  http://www.busconversions.com/bbs/index.php?action=printpage;topic=2267.0

Brian

[Garymci5]

Thanks very much for the info, Brian, I'll give it try!