My Needy GM PD4106!!

[Brother John]

I am trying to restore the entry and Drivers area to "stock" or close to it.  A previous owner removed the Crank and shaft that opens the door, the front panels below the dash, the louvered panels for the door, the accordion or pleated door hinge cover along with the rounded metal cover that screws on the dash, the grab rails for entry as well as the drivers seat grab rails and of course the driver's seat. I actually would like to find 2 driver seats... The bus also needs the Sun Visors and an original dash gauge holder and the riser it sits on... and the sheet metal cover for the vertical on drivers side close to Window.... Big List isn't it?! 

Mechanically the bus seems pretty sound.  I bought it in San Diego area two weeks ago and drove it 1300 miles to a bit north of Seattle WA.  My biggest complaint was the wheel has too much play... 12 to 1 o'clock.. always.  I've heard you can't adjust Sheppard power steering... tell me that ain't true??

So aside from the steering issue, I'm hoping that some of the converters on this forum know of someone with a parts bus or perhaps still have those "takeout items" stashed somewhere gathering dust??? Oh I could also use a stock Tailgate engine cover, (whatever you want to call it)  also looking for 12r22.5 tires... and a 2 stage air conditional for the basement..
Feel free to call: 425 286 3218
Thanks,
Brother John

[christopher]

luke at u s coach, vineland nj has some gm vintage buses gm  in the yard. call him
regards
chris
mi5c

[chessie4905]

first, are you sure it has sheppard power steering and not power assist that uses a hydraulic cylinder connected to steering box? On either system, there is a right angle gear box at bottom of steering column in compartment under driver. common with a lot of miles to have wear in these two gears. they use shims here to get proper clearance. shimming worn gears tighter will create binding off center. if sheppard was added to a previous manual steering coach, the gears in angle box will be 1.5 to 1. factory sheppard used 1 to 1, another words, fewer turns lock to lock. If you have the slower ratio, you can get the other gears from a 4905 with power steering.
from this box, there is a small driveshaft that connects it to steering box. common to have worn u-joints and slip joint here. you can check for play before steering box by putting two 24 inch or larger pipe wrenches, opposite to each other on the yoke at steering box and hold to keep yoke from rotating in either direction, while someone moves steering wheel cw and ccw. that is the play you have that isnt in box. btw, that driveshaft is tha same one that was used in old Army Jeeps. go figure.btw, the faster steering ratio will also lessen play.

[Friday1]

Play in the steering can be traced to many components. Starting at the steering wheel, there is a u-joint between the wheel and the floor, the right angle box in the driver compartment, a cover you lift in the driver compartment to lube the joint, a  flange bearing exiting the back of the compartment and its grease fitting is on the outside corner, a u-joint and slip joint, another u-joint at the axle and a grease fitting on the axle. The king pins, the tie rod ends, the drag link all are potential points that if worn will contribute to slop at the wheel.

[chessie4905]

There will also be a little unavoidable play in the air assist system due to its design.

[Brother John]

Chessie 4905 Thanks very much for the useful info!

Christopher, Thanks very much for the useful info!

I am aware that there are many areas that play can be created in steering... Hunting them!

I will be calling Luke.  I'm putting together a list of questions so I don't waste a lot of time...
Thanks,
brother john

[HB of CJ]

Loose steering can be fixed but usually at a high $cost$.  If memory serves, (suspect!) my old 1963 Crown Supercoach 40 foot 10 wheeler had air assist power steering.  The steering was very very tight.  No slop at all.  You could feel it when then air assist kicked in while circling, turning, etc..

Later my 1074 Crown Supercoach 10 wheeler with hydraulic power assist steering had extremely tight steering.   At 60 mph a slow lane change took only about 1/4 inch of swing.  The steering was so tight at first it was easy to over steer.  Felt like a sports car.  No slop at all.  You had to pay attention.

The 1974 Crown had exceptional good maintenance.  Lots of new front steering components.  Ross, (TRW) steering box, tie rod ends, etc.   Later a new bigger Victors (sp?) hydraulic pump and new long hoses.  The short story here is that tight steering can be had, but at a high cost.  I was lucky.  Long ago.