BAC Forum

General Boards => Technical Support => Topic started by: Mike Groves on March 27, 2017, 03:22:55 PM

Title: How low can I go?
Post by: Mike Groves on March 27, 2017, 03:22:55 PM
Has anyone done an air dump to enter an RV garage that close to being high enough but not quite.  I am curious has to how much I can lower my '99 Marquis.  I believe I am below 13ft in total height but the garage door is 12' 9".

Mike
Title: Re: How low can I go?
Post by: Gerald Farris on March 28, 2017, 02:52:45 PM
Mike,
Your coach should clear a 12'9" opening without a problem if it is level ground. As for dumping your air pressure to gain clearance, you do realize that a total air dump will apply the parking brake and make the base brakes inoperative don't you.

Gerald
Title: Re: How low can I go?
Post by: Lee Welbanks on March 28, 2017, 02:58:50 PM
Not sure about a 99 air suspension, on my 06 you can dump the air leveling to gain clearance and still have brakes. The book also states not to make any turns as the front tire will hit the wheel well.
Title: Re: How low can I go?
Post by: Joel Ashley on March 28, 2017, 07:57:24 PM
I've done that a couple of times to clear branches, but not all the way down as Gerald warns.  And I drove straight, did about 5 mph, and was on flat surfaces.

Joel
Title: Re: How low can I go?
Post by: Mike Groves on March 29, 2017, 02:48:31 PM
I checked the door height and it is 12' 9" on each side with an arc so its even greater by the time the center of the door (12' wide door) is reached so it extends more than 13' high in the middle of the door.

I have added 2 roof vent covers and there is a storage bin on the roof.  These two items are the highest but still probably under 13' so I am optimistic that I can do this without my finger on the air dump to lower the vehicle.

Regarding Gerald's thought on the brakes, if I am using the air dump on the leveler, is that also going to dump the brake reservoir and if not, then why would the brakes be an issue?

Mike
Title: Re: How low can I go?
Post by: Edward Buker on March 29, 2017, 05:28:54 PM
Mike,

When I did an air dump on mine both needles went down and there was a point where one needle stopped, think it may have been 50lbs which may be enough to hold the springs in the off position if that tank fed the safety brake spring chambers. Gerald is highlighting that you may need to test to see if your coach can be moved with whatever air reservoir pressure remains after an air dump. Safety brakes being off are not a given.

Later Ed