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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: GM0406 on April 28, 2014, 08:45:43 AM

Title: 4104 Sheppard Steering Box
Post by: GM0406 on April 28, 2014, 08:45:43 AM
Anybody got a tight one?  Mine has too much play and needs to be replaced.  Bill T.
Title: Re: 4104 Sheppard Steering Box
Post by: TomC on April 28, 2014, 01:53:59 PM
Have it rebuilt.
Title: Re: 4104 Sheppard Steering Box
Post by: luvrbus on April 28, 2014, 02:29:54 PM
Is it for sure the sector or all the hardware that is sloppy
Title: Re: 4104 Sheppard Steering Box
Post by: GM0406 on April 30, 2014, 02:10:03 PM
Well I don't know.  Ted has the coach right now as it is in Williams.  His first response was that it is the Sheppard box, but he is going to check further and get back to me.  Tom, your suggestion that the box be rebuilt is interesting, but I thought parts are not available for these any longer?  That is what Sheppard told me anyway and a new box is around $1000.  If there is an idler arm on these coaches, I would suspect that or linkage or something else.  Ted says some of these boxes had soft parts in them and if they were hardened properly would not have failed. 

I am getting pretty cautious with this coach as I think it was you, George Lowrey, Joe Alvarez, and Russ Hoit that listened to the vibration that turned out to be the pressure plate after I spent $15 K to replace the crank that was supposed to be the source for the vibration.  Then a shop got to checking for the vibration and found the crank endplay was way too much and they had to replace the crank.  After the crank was replaced the vibration was still there.  So out came the trans again and they replaced the PP, the disc, the TO bearing, and the wear plate.  Much better now, but not impressed with the pressure plate balancing guys.  Wonder why we don't have diaphragm pressure plates for these 671s?


Bill T.
Title: Re: 4104 Sheppard Steering Box
Post by: luvrbus on April 30, 2014, 02:25:52 PM
Buy you a standard flywheel and go for it I converted one to a diaphragm clutch the throw bearing setup gets a little tricky but not all that bad parts can be had from a truck salvage yard for the throw out bearing
Title: Re: 4104 Sheppard Steering Box
Post by: gus on April 30, 2014, 07:12:01 PM
The older Sheppards had built-in slack and this can't be changed.

I have this problem on my 4107 and have spent much time talking to the factory people.

The only option I have is living with it or spending about $2-3000 getting a custom model that will fit in place of my old one.

It is a pain but I can live with it.
Title: Re: 4104 Sheppard Steering Box
Post by: chessie4905 on May 01, 2014, 05:19:05 AM
   The box would be the last item I'd look into replacing. There are too many other places to look first. Hold the input shaft with two opposing pipe wrenches while someone wiggles the steering wheel right to left. Get rid of that play first, then check and fix/repair for loose drag link ends, tie rod ends and sloppy kingplns. Make sure you have some positive caster set into the axle and THEN deal with the box if you still have play/problem.
Title: Re: 4104 Sheppard Steering Box
Post by: GM0406 on May 01, 2014, 02:53:08 PM
Chessie,

I think this is a great summary along with all of the other input here.  I talked to Joe Alvarez yesterday and he suspects universals also.  I am going to copy your post to Ted and see what he responds.  I think the only way to test this rascal is to get it jacked up and check for play.   Bill T.
Title: Re: 4104 Sheppard Steering Box
Post by: GM0406 on May 01, 2014, 03:00:43 PM
Luvrbus,

Change the flywheel?  Why?  We can't get a diaphragm plate for a standard wheel?  Wouldn't be surprised if this damn spring plate was responsible for pounding out the thrust with this air clutch!!!  A diaphragm plate is a huge design advance and I can't believe spring plates are even still in existence. 

Bill T. 
Title: Re: 4104 Sheppard Steering Box
Post by: gg04 on May 01, 2014, 05:39:21 PM
Problem we found with the stock imbalance was the wear plate..San Antonio clutch and brake built me a disc and pressure plate and a oil field machine shop built me a perfectly balanced with my flywheel wear plate out of 1" boilerplate..been in for 90 something thousand miles behind my 6l71 Ta ddec...rdw