Home » Public Forums » GMCnet » Centering the steering box (what does that mean?)
| Centering the steering box [message #363521] |
Mon, 19 April 2021 10:23  |
boybach
Messages: 566
Registered: December 2020
Location: Vancouver Island
Karma: 4
|
Senior Member |
|
|
I've read through many threads in the archive on this subject as well as downloading instructions as to how to accomplish the task ..however, I still don't understand WHAT I'm supposed to be doing as well as WHAT I'm lining up to be centered and WHERE I look to find what it is I'm supposed to be looking at  
Could someone please explain to me the process, keeping in mind I have no idea what the steering box actually does never having seen one before this month - I've only ever dealt with hydraulic steering racks on my other vehicles and never had to muck about with them.
Help!
Larry
Larry - Victoria BC -
1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
|
|
|
|
| Re: Centering the steering box [message #363523 is a reply to message #363521] |
Mon, 19 April 2021 10:45  |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
In short, someone has messed with the tie rod adjusters over time. The box is then not pointing straight (exactly center) when going straight ahead. (This also puts the entire steering linkage off center creating other issues). The box on center is when the flat on the input shaft is parallel to the machined flat gasket surface where the cover is bolted on (and you are equal turns away from left or right). Once toe is reset to get box on center you can then check that the steering wheel matches scribes on the upper shaft. Finally you correct the miss assembled intermediate shaft permutations so that the shaft drops in top and bottom to the center of their keys.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
|
|
| Re: Centering the steering box [message #363526 is a reply to message #363521] |
Mon, 19 April 2021 11:46 |
boybach
Messages: 566
Registered: December 2020
Location: Vancouver Island
Karma: 4
|
Senior Member |
|
|
OK!
I'm afraid my steering component vocabulary is rather limited ATM; no doubt I will become familiar with the terms as time goes on, but for now I have no clear picture in my mind of where, what and how.
What I do have, is my coach with the grille removed, the blue shaft marked and removed ready for boot refit. So I'm looking down at the steering box, the wheels are straight ahead and the steering wheel is locked and appears straight. What do I look at and do I look from above or below, at the left or right side? All I want to do at this time is see if it's centered.
Thanks
Larry
Larry - Victoria BC -
1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
|
|
|
|
|
|
|
|
| [GMCnet] Re: Centering the steering box [message #363531 is a reply to message #363528] |
Mon, 19 April 2021 17:10 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
I don't know where the photos are, but someone, 'way back, showed clamping
a steel bar to the flat on the input shaft to make it easier to visually
align to the assembly flat, as shown in Rob's photo.
Ken H.
On Mon, Apr 19, 2021 at 2:57 PM Bill Van Vlack
wrote:
> Here's some photos thanks to Rob Mueller.....
>
>
> http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p56547-steering-box-input-shaft-alignment.html
>
>
> --
> Bill Van Vlack
> '76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath,
> Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o
> mid
> November 2015.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
|
|
|
|
| [GMCnet] Re: Centering the steering box [message #363534 is a reply to message #363532] |
Mon, 19 April 2021 20:54 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
Most alignment shops start out by turning the steering wheel to achieve the
correct toe in/out. Then, they adjust the tie rod ends on the other side of
the of the vehicle to correct the toe in/out. This results in moving the
center of the steering box. They then remove the steering wheel and point
it straight ahead. This works, sort of, on rear wheel drive vehicles, but
not on a GMC with front wheel drive. Makes them wander. To really do it
right, an adjustable drag link is very helpful. More complex than space
here permits for explanation in detail. Go on Jerry Work's web site, "The
dovetail joint", he has a very detailed alignment procedure there.
Jim Hupy
Salem, Oregon
On Mon, Apr 19, 2021, 4:27 PM Larry wrote:
> boybach wrote on Mon, 19 April 2021 16:04
>> Thanks Bill, that's what I needed. I can see what everyone is talking
> about now :)
>>
>> Larry
>
> The best set of pics is the ones that Bill VV pointed out. Pics by Alex F.
>
> http://www.gmcmhphotos.com/photos/steering-box/p54238-steering-box-adjustment.html
>
> Use the right arrow on pics to advance.
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
|
|
|
|
| Re: [GMCnet] Re: Centering the steering box [message #363536 is a reply to message #363534] |
Mon, 19 April 2021 22:21 |
boybach
Messages: 566
Registered: December 2020
Location: Vancouver Island
Karma: 4
|
Senior Member |
|
|
James Hupy wrote on Mon, 19 April 2021 18:54Most alignment shops start out by turning the steering wheel to achieve the
correct toe in/out. Then, they adjust the tie rod ends on the other side of
the of the vehicle to correct the toe in/out. This results in moving the
center of the steering box. They then remove the steering wheel and point
it straight ahead. This works, sort of, on rear wheel drive vehicles, but
not on a GMC with front wheel drive. Makes them wander. To really do it
right, an adjustable drag link is very helpful. More complex than space
here permits for explanation in detail. Go on Jerry Work's web site, "The
dovetail joint", he has a very detailed alignment procedure there.
Jim Hupy
Salem, Oregon
Thanks for that, James. Jerry Work's method looks good and his explanation of caster and camber etc is pretty great.
Larry
Larry - Victoria BC -
1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
|
|
|
|
|
|
| Re: Centering the steering box [message #363564 is a reply to message #363521] |
Tue, 20 April 2021 17:56 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
The adjustable drag link adds complexity in that it’s another place to be wrong. It is for very fine nuisance adjustment correction only. Adding and misusing adjustable drag link you can then have box on on center, wheel at 12 and have the steering linkage off to one side, meaning relay and idler not straight. You will be able to turn further one way than other and amount of turn in toe will be asymmetrical.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
| Re: Centering the steering box [message #363568 is a reply to message #363521] |
Tue, 20 April 2021 23:01 |
boybach
Messages: 566
Registered: December 2020
Location: Vancouver Island
Karma: 4
|
Senior Member |
|
|
Ok, well I had a good look at the Mueller steering inspection guide and from his description/picture of the spline bolt position on the U-joint I believe my steering box could be 60 or so degrees off center. I intend to correct this if I can.
As I understand it, the pitman arm and the drag link have to be separated so I can center the box - I'm guessing I need a pickle fork to do that?
Larry
Larry - Victoria BC -
1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
|
|
|
|
|
|
| Re: Centering the steering box [message #363582 is a reply to message #363572] |
Wed, 21 April 2021 10:26 |
boybach
Messages: 566
Registered: December 2020
Location: Vancouver Island
Karma: 4
|
Senior Member |
|
|
RF_Burns wrote on Wed, 21 April 2021 04:02The pitman arm has a keyway so it only goes on one way. If you don't have an adjustable drag-link, then you need to adjust the tie rod end couplers on each side to bring the steering box on center.
I do have an adjustable drag-link, but could anybody please confirm my plan to center the steering box?
I have the lower steering shaft marked, greased, re-booted and disconnected but the blue shaft sleeve U-joint is still attached to the input spline on the steering box. I am about to remove the sleeve to expose the steering box input spline.
The way I understand it, I need to center the spline as per Mr. Mueller's guide, using a 3/4" 12 point socket, and in order to turn the spline to center, the pitman arm has to be disconnected from the drag-link. How do I disconnect it? I can see it has a castellated nut and split-pin - do I need to use a ball joint separator (pickle fork) to do that or will it simply release?
After the adjustment, is it straightforward to re-connect the pitman arm? I imagine it will be in a very different position than when it was released - are you suggesting I change the length of the drag-link to accommodate the new setting? That does make sense, but JohnL455 said it would be a no-no to make a large change, so I'm guessing the better plan is to adjust both tie rods the same amount to move the drag link into the new position?
Taking a day off today to get the plan thoroughly worked out before I dive into the job.
All input, gotchas, and advice sincerely appreciated - I've owned the coach exactly one month TODAY!
Thanks in advance
Larry
Larry - Victoria BC -
1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
|
|
|
|
| Re: Centering the steering box [message #363586 is a reply to message #363521] |
Wed, 21 April 2021 11:39 |
 |
RF_Burns
Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada
Karma: 3
|
Senior Member |
|
|
Here is Ken Henderson's verbal write-up.. and note at the end he says the pitman arm does not need to come off... it only goes on one way!
http://www.gmcmhphotos.com/photos/data/6588/steering.pdf
Having done mine and checked it several times, this is how I would doing it again from scratch.
If your coach drives straight and no funny wear on the tires, then you can assume you have the front wheels aligned right, or close anyway. Take your coach out for a quick test drive and determine the steering wheel position when the coach is going straight down the road. When you come back home, drive the last 10 feet with the steering wheel in the position you had noted on your test drive. You now have your front wheels pointing straight ahead (just maybe not the steering wheel!)
Open the engine cover and look down at the position of the relay arm and idler arm. They should be pointing straight back, parallel with the main ladder frame. If not, then the link between the tie-rods out to wheels is off of its center point of movement. Use the tie-rod adjustment sleeves to get the relay arm and idler arm in the center of their swing (straight back, parallel with the chassis frame). Turn the sleeves a little bit on each side, alternating side to side and in the opposite direction so you do not move the front wheel position. You only want to shift the connecting rod to the center of its movement by setting the relay arm and idler arm point straight back.
Now you have your wheels pointing straight ahead and the relay arm in the center of its movement swing.
Next you need to get your steering box at the high point. Pull the intermediate shaft universal joint off the input shaft to the steering box. Use your adjustable drag-link to line up the flat on the input shaft to be parallel to the cover plate on steering box as shown in Alex's photos here: Turning the drag-line adjustment will make the steering box input shaft move.
http://www.gmcmhphotos.com/photos/steering-box/p54239-photo-2.html
At this point you have your wheels straight ahead and your steering box set on high-point. Now you need to get your steering wheel set so it is at 12 o'clock. You need to align the u joint to the input shaft next. Read Ken's instructions from his PDF above (I think the drill is actually 15/32") If you are lucky your steering wheel will be at 12 o'clock. Otherwise you will need to follow Alex's and Ken's instructions to reclock the intermediate steering shaft assembly. The steering wheel should be at 12 o'clock position when the steering box is at high-point. Your should not need to change these adjustments from the steering wheel to the steering box again.
When you have done all that, take it for a test run. If you find the steering wheel is a bit off 12 o'clock when going straight, you can use the drag link to fine adjust it so the box is at high point when you are driving down the road.
Photos and more instructions here:
http://www.gmcmhphotos.com/photos/g6588-steering-box.html
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
|
|
|
|
| Re: Centering the steering box [message #363587 is a reply to message #363521] |
Wed, 21 April 2021 11:54 |
boybach
Messages: 566
Registered: December 2020
Location: Vancouver Island
Karma: 4
|
Senior Member |
|
|
Thanks Bruce, will digest your post in full later on! Much appreciated
Thanks
Larry
Larry - Victoria BC -
1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
|
|
|
|
| [GMCnet] Re: Centering the steering box [message #363588 is a reply to message #363586] |
Wed, 21 April 2021 11:43 |
sgltrac
Messages: 2797
Registered: April 2011
Karma: 1
|
Senior Member |
|
|
Nice info Bruce.
Sully
Bellevue wa.
On Wed, Apr 21, 2021 at 9:40 AM Bruce Hislop wrote:
> Here is Ken Henderson's verbal write-up.. and note at the end he says the
> pitman arm does not need to come off... it only goes on one way!
>
> http://www.gmcmhphotos.com/photos/data/6588/steering.pdf
>
> Having done mine and checked it several times, this is how I would doing
> it again from scratch.
>
> If your coach drives straight and no funny wear on the tires, then you can
> assume you have the front wheels aligned right, or close anyway. Take your
> coach out for a quick test drive and determine the steering wheel position
> when the coach is going straight down the road. When you come back home,
> drive the last 10 feet with the steering wheel in the position you had
> noted on your test drive. You now have your front wheels pointing straight
> ahead (just maybe not the steering wheel!)
>
> Open the engine cover and look down at the position of the relay arm and
> idler arm. They should be pointing straight back, parallel with the main
> ladder frame. If not, then the link between the tie-rods out to wheels is
> off of its center point of movement. Use the tie-rod adjustment sleeves to
> get the relay arm and idler arm in the center of their swing (straight
> back, parallel with the chassis frame). Turn the sleeves a little bit on
> each
> side, alternating side to side and in the opposite direction so you do not
> move the front wheel position. You only want to shift the connecting rod to
> the center of its movement by setting the relay arm and idler arm point
> straight back.
>
> Now you have your wheels pointing straight ahead and the relay arm in the
> center of its movement swing.
>
> Next you need to get your steering box at the high point. Pull the
> intermediate shaft universal joint off the input shaft to the steering box.
> Use
> your adjustable drag-link to line up the flat on the input shaft to be
> parallel to the cover plate on steering box as shown in Alex's photos here:
> Turning the drag-line adjustment will make the steering box input shaft
> move.
>
> http://www.gmcmhphotos.com/photos/steering-box/p54239-photo-2.html
>
> At this point you have your wheels straight ahead and your steering box
> set on high-point. Now you need to get your steering wheel set so it is at
> 12
> o'clock. You need to align the u joint to the input shaft next. Read
> Ken's instructions from his PDF above (I think the drill is actually
> 15/32") If
> you are lucky your steering wheel will be at 12 o'clock. Otherwise you
> will need to follow Alex's and Ken's instructions to reclock the
> intermediate
> steering shaft assembly. The steering wheel should be at 12 o'clock
> position when the steering box is at high-point. Your should not need to
> change
> these adjustments from the steering wheel to the steering box again.
>
> When you have done all that, take it for a test run. If you find the
> steering wheel is a bit off 12 o'clock when going straight, you can use the
> drag
> link to fine adjust it so the box is at high point when you are driving
> down the road.
>
> Photos and more instructions here:
>
> http://www.gmcmhphotos.com/photos/g6588-steering-box.html
>
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
Sully
77 Royale basket case.
Future motorhome land speed record holder(bucket list)
Seattle, Wa.
|
|
|
|
| Re: Centering the steering box [message #363589 is a reply to message #363587] |
Wed, 21 April 2021 12:15 |
Bill Van Vlack
Messages: 419
Registered: September 2015
Location: Guemes Island, Washington
Karma: 14
|
Senior Member |
|
|
Great write-up, Bruce..
A suggestion... I found that my steering wheel marks were not lined up; they were one spline off. Perhaps after the first ride remove the steering wheel, check the marks, and re-install with them lined up.
Bill Van Vlack
'76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath, Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o mid November 2015.
[Updated on: Wed, 21 April 2021 12:17] Report message to a moderator |
|
|
|
Goto Forum:
Current Time: Fri Jul 05 03:10:35 CDT 2024
Total time taken to generate the page: 0.08258 seconds
|
GMCforum
Search
Help
Register
Login
Home
