-
tag lift
-
Jon I have had my tag air chanbers replaced after they broke off, work done at Prevost. I don’t remember if the tags came off the ground before the replacement but I know they don’t now. When some of the guys where saying they could lift the wheels off the ground I thought that maybe my chains were not adjusted right during the fix. I’ll let it alone and use blocks to get the wheels off the ground if needed.
-
Just to clarify… by few minutes I mean 10-20 with a maximum of 30 but honestly I haven’t even checked latley because I usually dump the tags before I shut down and then lower the front to level. I have an electric auxillary compressor but I have never used it. I have turned it on but only for a few minutes at a time to see if it worked. I will try to see if it will keep up but if the leaks are as bad as you all think it may not.
You guys are a big help…
DKO
-
Greg,
This is a rough way to check tag axle lift chain length……..raise your coach to its maximum height using the air bags. At the maximum height the chain should have no slack, but should not be beginning to lift the tag axle.
The lifting chambers are a #30 or #36 brake chamber (I can’t remember which) and as long as there has been no change in coach air pressure there is no reason they should not lift the tag. You do have to wait until the drive axle air bags restore the coach to the normal ride height. Assuming your rear weight is around 27,000 pounds the four drive axle air bags should be capable of restoring the coach to ride height with the tag axle clear of the ground. The tag lift chambers are pressurized via a valve located on the frame behind the Norgren that opens or closes the air path between the drive and tag air bags. That valve functions like a Norgren and if the aux air system has had moisture in it or if the valve has not been exercised it might not be fully opening. A quick check is to raise and support the rear of the coach, then apply regulated air pressure to the tag axle lift chambers. Increase the pressure and observe the function of the tag lift chambers. Do not exceed 125 PSI.
-
Greg,
The 40 footers will lift the tag off the ground pretty quick, but the 45’s take awhile. My 2000 45′ would not lift the tag for short maneuvering and I never let it set long enough with the engine running to see if it would eventually come up.
-
The weight comes off the tags but they do not raise high enough to freely turn the wheels.
-
I can and have changed tag wheel on both buses by lifting the tag. Both a 40 footer and a 45. The difference is like Tom says. The forty footer would lift quickly, the 45 took quite a while but the tag still cleared the ground.
I think the difference relates to the geometry of the two lengths. With the longer overhang of the 45 more weight is supported on the drive axle when the tag is lifted, on my coaches the difference is about 6000 pounds. The drive axle air bags are the smaller of the two types used on our coaches so you likely have to go through several cycles of the engine driven compressor before you can get the max system pressure in the air bags so the drive axle air bags can actually lift the entire rear of the coach.
Owners of coaches heavy on the steer axle know exactly what that is like because in order to raise the front of heavily loaded front axle coaches some either have to wait for numerous air cycles of the compressor, or they have to raise the tag to transfer weight off the steer axle to the drive, an option not available when trying to lift the tag.
Lifting tag axles is over rated. I rarely have felt the need to lift the tag, but if I have to make a turn and do it in the shortest -possible distance I will break down and flip the switch. On 45 foot coaches I think the best that can be expected under normal circumstances when “lifting” the tag is to reduce the ground pressure and thus minimize sidwards scuffing. More than anything I find myself raising the coach or portions of the coach so as to not drag or high center the coach.
Log in to reply.