SUSPENSION ADJUSTMENT PART 2, BOGIE AXLE RE-INDEXING
Posted: Sat Oct 25, 2008 10:37 am
Please make sure to follow the instructions in the order that has been described. Do not skip the factory designed steps.
If you have determined that the bogie axle needs adjusting, then you will have to re-index the fixing arm on the torsion bar since there is no adjustment rod on the bogie. The adjustment arm is splined to mount onto the torsion bar. Adjusting one spline will increase the weight approximately 500 pounds, depending on the wear in the torsion bar.
First, leave the coach jacked up using the bottle jacks to the ride height desired.
Next, place a bottle jack under the end of the fixing arm to remove the tire. Only jack it up until it just clears the ground, just like when you weighed the bogie.
Once you have removed the tire, measure from the center of the hub to the ground and record this measurement. This will come in handy later.
Remove the lower end of the shock, disconnect the air line to the brakes and lube the splines on the fixing arm and mounting bolts.
Adjust the brakes to lock the brake drum. Place a floor jack under the brake drum and remove the bottle jack.
Remove the two mounting bolts on the end of the fixing arm.
Using a center punch, mark the splines on the fixing arm and the torsion bar so that you have a reference as to where you started.
Do not use a wedge or chisel to spread the fixing arm. I once tried this and the chisel went flying about thirty feet across the shop, very dangerous. Also, you may deform the arm and not be able to retain the clamping force when reinstalling the end bolts. This will cause the splines on the fixing arm and torsion to become rounded and loose. Then you are looking at replacing both the arm and the torsion.
The fixing arm is only splined half way through, so you do not need to remove completely.
I found that the easiest way to remove the fixing arm is to use a puller. Many implement dealers have these large pullers.
Before you remove the fixing arm, let the floor jack down to relieve the pressure on the fixing arm and then jack it back up just until you have a slight bit of pressure on the fixing arm. This will allow you to use the floor jack to guide the fixing arm off of the torsion end and support it so that it does not fall.
Once you have removed the fixing arm half way, then slowly let the floor jack down until you have traveled the distance of how many splines you needed to adjust, lubricate the splines with never seize and then push the fixing arm back onto the torsion splines.
Check the marks you made on the splines to determine if you have re-indexed the arm to the determined amount.
If you have, then install the bolts back onto the end of the fixing arm. Depending on how many splines you moved, it may be necessary to drill out the bolt hole that goes through the splines on the torsion bar.
Place the bottle jack with the pressure gauge back under the end of the fixing arm and jack it up to remove the floor jack.
Using the measurement that you took earlier from the center of the hub to the ground, adjust the bottle jack until you have this measurement. Once you have, then check the pressure gauge to see of you have achieved the weight you desired. Add about 150 lbs. for the wheel and tire. If you have achieved the weight desired, then, reassemble everything and adjust your brake that was locked in place.
I am writing this from memory, so if I have left anything out or any of you have questions, please let me know.
Mount the tire and you are finished. Pretty easy, yeah right
Dan Lenz
If you have determined that the bogie axle needs adjusting, then you will have to re-index the fixing arm on the torsion bar since there is no adjustment rod on the bogie. The adjustment arm is splined to mount onto the torsion bar. Adjusting one spline will increase the weight approximately 500 pounds, depending on the wear in the torsion bar.
First, leave the coach jacked up using the bottle jacks to the ride height desired.
Next, place a bottle jack under the end of the fixing arm to remove the tire. Only jack it up until it just clears the ground, just like when you weighed the bogie.
Once you have removed the tire, measure from the center of the hub to the ground and record this measurement. This will come in handy later.
Remove the lower end of the shock, disconnect the air line to the brakes and lube the splines on the fixing arm and mounting bolts.
Adjust the brakes to lock the brake drum. Place a floor jack under the brake drum and remove the bottle jack.
Remove the two mounting bolts on the end of the fixing arm.
Using a center punch, mark the splines on the fixing arm and the torsion bar so that you have a reference as to where you started.
Do not use a wedge or chisel to spread the fixing arm. I once tried this and the chisel went flying about thirty feet across the shop, very dangerous. Also, you may deform the arm and not be able to retain the clamping force when reinstalling the end bolts. This will cause the splines on the fixing arm and torsion to become rounded and loose. Then you are looking at replacing both the arm and the torsion.
The fixing arm is only splined half way through, so you do not need to remove completely.
I found that the easiest way to remove the fixing arm is to use a puller. Many implement dealers have these large pullers.
Before you remove the fixing arm, let the floor jack down to relieve the pressure on the fixing arm and then jack it back up just until you have a slight bit of pressure on the fixing arm. This will allow you to use the floor jack to guide the fixing arm off of the torsion end and support it so that it does not fall.
Once you have removed the fixing arm half way, then slowly let the floor jack down until you have traveled the distance of how many splines you needed to adjust, lubricate the splines with never seize and then push the fixing arm back onto the torsion splines.
Check the marks you made on the splines to determine if you have re-indexed the arm to the determined amount.
If you have, then install the bolts back onto the end of the fixing arm. Depending on how many splines you moved, it may be necessary to drill out the bolt hole that goes through the splines on the torsion bar.
Place the bottle jack with the pressure gauge back under the end of the fixing arm and jack it up to remove the floor jack.
Using the measurement that you took earlier from the center of the hub to the ground, adjust the bottle jack until you have this measurement. Once you have, then check the pressure gauge to see of you have achieved the weight you desired. Add about 150 lbs. for the wheel and tire. If you have achieved the weight desired, then, reassemble everything and adjust your brake that was locked in place.
I am writing this from memory, so if I have left anything out or any of you have questions, please let me know.
Mount the tire and you are finished. Pretty easy, yeah right
Dan Lenz