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Front Ride Height Adjustment - Balance Beam [message #336066] Mon, 13 August 2018 20:27 Go to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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I recently heard of using a 'balance beam' across the rear bogies to set front ride height. A pipe is welded fore and aft at the center of the beam, and used as a pick point for a jack. As I imagine the process, you set rear ride height to spec. Raise the jack to just start to pick up the load and then let air out of the bags until all the weight is carried by the beam. Then use the adjusters to re-level the coach and set to factory ride height.

I recently reset my ride height by the trial and error method, driving between adjustments. If this procedure works the first time, it would save a bunch of time. On a lift with a cross platform it would be even easier.

Anyone tried this, heard of it, or have an opinion?


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.
Re: Front Ride Height Adjustment - Balance Beam [message #336072 is a reply to message #336066] Tue, 14 August 2018 06:07 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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That is a lot of extra and nothing extra accomplished.

To set the FRONT ride height simply cut two 2x4s exactly the same length and at the rear ride height value. Then drop the coach on them until a little weight is resting on both 2x4s. All you are trying to do is block the rear ride height in place while you make fr0nt adjustments. Now the rear (both sides) are stationary and equal. They will not be affected as you make adjustments to the front. When you are finished with the front, air it up again and take it for a ride of 5 or 10 miles to let the rear leveling switches readjust for any weight changes.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Front Ride Height Adjustment - Balance Beam [message #336084 is a reply to message #336072] Tue, 14 August 2018 10:40 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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Location: Guemes Island, Washington
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Agree, the time/expense to make the balance beam isn't worth it for a single height adjustment for the average owner.

When a friend and I did a ride height adjustment recently, we unloaded the suspension each time by jacking up the front end and it took us two adjustments with a drive to settle the suspension after the adjustment.

Do most folks do the adjustments with the suspension loaded and no settling drives? How many rounds of adjustment are typical?

If this procedure can set height with one adjustment without unloading the suspension and a lift was available, I'm wondering if it would be worth it for a Club to fabricate the beam. You could get quite a few height adjustments done in a day.


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.
Re: Front Ride Height Adjustment - Balance Beam [message #336088 is a reply to message #336066] Tue, 14 August 2018 11:54 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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I fail to understand what the beam is buying you. Lock the rear height in place on a couple of equal wood blocks with a couple hundred pounds downward force on each rear block. That is all you need to keep it from moving. Then go adjust the height.

If you have a torsion bar unloader you can adjust the front height with the wheels on the ground. Once set with the unloader, raise the adjusting screw into place to hold the adjustment there. Do not attempt to adjust the height using just the adjusting screw without the torsion bar unloader taking the load.

I usually have to adjust it twice, driving in between to get them set accurately.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Front Ride Height Adjustment - Balance Beam [message #336091 is a reply to message #336084] Tue, 14 August 2018 14:58 Go to previous messageGo to next message
dan molnes is currently offline  dan molnes   United States
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Ken when you set the front do you lift the the front end with a jack first

Sent from my iPhone

> On Aug 14, 2018, at 8:40 AM, Bill Van Vlack wrote:
>
> Agree, the time/expense to make the balance beam isn't worth it for a single height adjustment for the average owner.
>
> When a friend and I did a ride height adjustment recently, we unloaded the suspension each time by jacking up the front end and it took us two
> adjustments with a drive to settle the suspension after the adjustment.
>
> Do most folks do the adjustments with the suspension loaded and no settling drives? How many rounds of adjustment are typical?
>
> If this procedure can set height with one adjustment without unloading the suspension and a lift was available, I'm wondering if it would be worth it
> for a Club to fabricate the beam. You could get quite a few height adjustments done in a day.
> --
> 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:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: Front Ride Height Adjustment - Balance Beam [message #336094 is a reply to message #336066] Tue, 14 August 2018 16:37 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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Dan,
Here's a discussion about that....

http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&goto=292808&rid=4947&srch=ride+height#msg_292808

It would be nice to know the allowable torque on the Kent-Moore tool center bolt.


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.
Re: [GMCnet] Front Ride Height Adjustment - Balance Beam [message #336095 is a reply to message #336094] Tue, 14 August 2018 17:03 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Bill, I have installed a bunch of 1 ton front ends. I block the rear frame
at ride height on each side with custom made jack stands placed under the
oval slotted holes in the frame behind the rear/rear bogies.
Then, I place a torsion bar tool on each side and jack up the center
of the front cross member until the coach is at ride height on both sides
of the coach. Then, I tighten the center screws on the torsion bar tools
until it loosens the pork chop adjusters. Then, I totally remove the pork
chop adjustment bolts and nuts, wire wheel them and chase the threads with
taps and dies, lube them with nevr-seez, and put them back together. Adjust
what you think will be correct ride height, and test drive the coach.
REPEAT AS NECESSARY. ONLY AFTER CORRECT RIDE HEIGHT IS ACHIEVED, IS WHEEL
ALIGNMENT POSSIBLE., so do not waste time or money on alignment until ride
height is correct.
Jim Hupy

On Tue, Aug 14, 2018, 2:43 PM Bill Van Vlack
wrote:

> Dan,
> Here's a discussion about that....
>
>
> http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&goto=292808&rid=4947&srch=ride+height#msg_292808
>
> It would be nice to know the allowable torque on the Kent-Moore tool
> center bolt.
>
> --
> 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:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Front Ride Height Adjustment - Balance Beam [message #336100 is a reply to message #336095] Tue, 14 August 2018 19:35 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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Registered: September 2015
Location: Guemes Island, Washington
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Senior Member
Thanks, Jim.
Couple questions... Assume you place the rear on the jack stands by lowering the coach using the air bags, correct? For the front, are you unloading the torsion bars with the wheels on the ground and the control arms loaded? If so, how do you set front to ride height if the coach is too high?

I bought new bolts and nuts for the pork chop and used never-seize. Jacked front, unloaded torsion bar, measured adjusting bolt position and removed and replaced bolts and nuts. Assumed 1/8" per turn and adjusted trial level, loaded torsion bar, lowered coach, drove, measured, and repeated until it was in spec.

Once set(PS 3/16" low, DS 1/16" low), I aligned it. Camber PS, -0.2, DS +0.1; Caster PS 4.08, DS 3.81; Toe 3/32" out.


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.
Re: [GMCnet] Front Ride Height Adjustment - Balance Beam [message #336103 is a reply to message #336100] Tue, 14 August 2018 20:55 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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Senior Member
I could go into exact detail, and have the moderator after me. Yes, the air
bags need to lower the coach onto the stands.
On the front, it usually only takes a couple of strokes on my high
lift jack to get to ride height. That just makes it easier to hand crank
the tools. Either way will work. Just be sure to drive the coach after
adjustments.
Jim Hupy

On Tue, Aug 14, 2018, 5:53 PM Bill Van Vlack
wrote:

> Thanks, Jim.
> Couple questions... Assume you place the rear on the jack stands by
> lowering the coach using the air bags, correct? For the front, are you
> unloading the torsion bars with the wheels on the ground and the control
> arms loaded? If so, how do you set front to ride height if the coach is too
> high?
>
> I bought new bolts and nuts for the pork chop and used never-seize. Jacked
> front, unloaded torsion bar, measured adjusting bolt position and removed
> and replaced bolts and nuts. Assumed 1/8" per turn and adjusted trial
> level, loaded torsion bar, lowered coach, drove, measured, and repeated
> until it
> was in spec.
>
> Once set(PS 3/16" low, DS 1/16" low), I aligned it. Camber PS, -0.2, DS
> +0.1; Caster PS 4.08, DS 3.81; Toe 3/32" out.
>
> --
> 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:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Front Ride Height Adjustment - Balance Beam [message #336105 is a reply to message #336091] Tue, 14 August 2018 22:54 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Location: Hebron, Indiana
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dan molnes wrote on Tue, 14 August 2018 14:58
Ken when you set the front do you lift the the front end with a jack first


No. I measure the current front height and then figure if I need to go up or down and how far. I install the torsion bar unloader, de-adjust the stop bolt and adjust the heights with the unloader. Then I reinstall the adjustment bolt which is really a stop to hold the position. Finally I remove the unloader.

With that said, I also have a set of scales. So I usually do what is needed on the scales. It is much more accurate and in my opinion easier.

What I do is to place the rear on the blocks. It only take a few minutes as most of the rear weight is still on the tires. Then measure the front heights and decide how much I will need to move the front. It is rare to find one too high. Then I pull on the scales and block the rear again. I measure the front height again to see how much the scales lifted the front. I now know what I want to accomplish. Reading the scales I adjust torsion bars for equal (within 100 pounds) weight on the front wheels. With the weight equal I adjust the front bars equally to get the correct ride height(s).

Note
1: a 1/4" difference between the two front wheels will transfer 125 pounds between the front wheels.
2: I have seen several coaches where people tried to adjust the front ride height without blocking the rears. They usually end up with opposite corners heavy. One coach I checked had a 775 pound difference on the fronts but the front ride heights were correct.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Front Ride Height Adjustment - Balance Beam [message #336113 is a reply to message #336105] Wed, 15 August 2018 11:02 Go to previous message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
Messages: 419
Registered: September 2015
Location: Guemes Island, Washington
Karma: 14
Senior Member
Couple of different approaches to using the tool by folks that have done more than a few of these... Front wheels up, suspension unloaded, and drives between adjustments - or, front wheels down and unloading against full torsion - no drives.

Using the tool without raising the front wheels is appealing to me if I ever do this again, just because of the time it takes to jack, mount tool, unload, adjust, remove tool, lower, and drive for each measurement.

On the other hand, I borrowed a couple tools (not Kent-Moore) and managed to damage them getting the coach raised (front wheels up), so it seems risky to make it worse by not jacking the front. On the third hand, I bought the Kent-Moore tool to replace them and things went smoothly after that (raising the coach between adjustments). Maybe it would have worked fine just leaving the coach on the ground; it has for others (and is the procedure in the workshop manual for my 76).



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.
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